(19)
(11)EP 3 190 697 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
20.05.2020 Bulletin 2020/21

(21)Application number: 15838205.1

(22)Date of filing:  02.09.2015
(51)International Patent Classification (IPC): 
G01K 13/08(2006.01)
H02K 21/00(2006.01)
H02P 29/60(2016.01)
G01R 31/34(2020.01)
H02P 29/66(2016.01)
G01K 7/42(2006.01)
(86)International application number:
PCT/CN2015/088807
(87)International publication number:
WO 2016/034114 (10.03.2016 Gazette  2016/10)

(54)

ROTOR TEMPERATURE MONITORING METHOD AND SYSTEM FOR PERMANENT MAGNET SYNCHRONOUS MOTOR

ROTORTEMPERATURÜBERWACHUNGSVERFAHREN UND SYSTEM FÜR SYNCHRONE PERMANENTMAGNETMOTOREN

PROCÉDÉ ET SYSTÈME DE SURVEILLANCE DE TEMPÉRATURE DE ROTOR POUR MOTEUR SYNCHRONE À AIMANT PERMANENT


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 05.09.2014 CN 201410452142

(43)Date of publication of application:
12.07.2017 Bulletin 2017/28

(73)Proprietor: CRRC Zhuzhou Electric Locomotive Research Institute Co., Ltd.
Zhuzhou Hunan 412001 (CN)

(72)Inventors:
  • FENG, Jianghua
    Zhuzhou Hunan 412001 (CN)
  • SHANG, Jing
    Zhuzhou Hunan 412001 (CN)
  • XU, Junfeng
    Zhuzhou Hunan 412001 (CN)
  • WEN, Yuliang
    Zhuzhou Hunan 412001 (CN)
  • LIU, Xiong
    Zhuzhou Hunan 412001 (CN)
  • ZHANG, Chaoyang
    Zhuzhou Hunan 412001 (CN)
  • XIAO, Lei
    Zhuzhou Hunan 412001 (CN)
  • HE, Yaping
    Zhuzhou Hunan 412001 (CN)
  • NAN, Yonghui
    Zhuzhou Hunan 412001 (CN)
  • ZHENG, Hanfeng
    Zhuzhou Hunan 412001 (CN)

(74)Representative: Sharman, Thomas Alexander 
Reddie & Grose LLP The White Chapel Building 10 Whitechapel High Street
London E1 8QS
London E1 8QS (GB)


(56)References cited: : 
WO-A1-2005/041397
CN-A- 102 072 778
CN-A- 104 158 463
US-A1- 2011 181 217
WO-A2-2014/041422
CN-A- 103 888 041
US-A1- 2011 144 843
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description


    [0001] The present invention relates to a method of monitoring a temperature of a rotor of a permanent magnet synchronous motor and a temperature monitoring system for monitoring a temperature of a rotor of a permanent magnet synchronous motor.

    BACKGROUND



    [0002] In an existing permanent magnet synchronous motor, it is necessary to provide a temperature sensor to monitor a temperature of the motor. Different permanent magnet materials have different temperature characteristics, and in general, magnetic field intensity of a permanent magnet weakens linearly as temperature increases, and enhances linearly as the temperature decreases. The magnetic field intensity of the permanent magnet always changes linearly in a certain range of the temperature. However, the magnetic field intensity of the permanent magnet reduces sharply and even the permanent magnet loses magnetism in a case that the temperature is exceed a critical temperature (also referred to as the Curie temperature). This process is irreversible, that is, the magnetic field intensity of the permanent magnet will not recover even if the temperature is reduced to be lower than the Curie temperature, and the permanent magnet has suffered irreversible damage, which is the reason for monitoring a temperature of a permanent magnet in a rotor of the permanent magnet motor in a real-time manner, in order to protect the rotor of the permanent magnet motor. The objective of monitoring the temperature of the motor is to, in a first aspect, protect the permanent magnet from losing magnetism due to a high temperature of the motor, and in a second aspect, derive a change in magnetic linkage of the permanent magnet, so as to correct torque output of the permanent magnet motor by compensating a magnetic linkage parameter of the permanent magnet.

    [0003] However, some problems are caused by the temperature sensor installed in the existing permanent magnet synchronous motor. That is, by using a dedicated temperature sensor, not only system cost is increased, but also system fault points are added, which decreases the system reliability.

    [0004] In addition, the temperature sensor can be installed only in a stator core of the permanent magnet motor, and there is time delay of thermal conduction between the rotor and the stator core. Therefore, protection for the permanent magnet and compensation for the magnetic linkage parameter cannot be timely and accurate.

    [0005] US patent publication number US2011/144843 provides a method of controlling a vehicle including a permanent magnet (PM) synchronous motor. The motor is controlled based on direct-axis (d-axis) and quadrature-axis (q-axis) current commands. The method includes estimating permanent magnet flux linkage based on q-axis voltage and electrical angular speed, and estimating permanent magnet temperature based on permanent magnet flux linkage and the temperature coefficient of the permanent magnet. The vehicle is controlled based on the estimated permanent magnet temperature.

    SUMMARY



    [0006] In view of the above, a method for monitoring a temperature of a rotor of a permanent magnet synchronous motor is provided according to the present disclosure, to monitor the temperature of the rotor of the permanent magnet synchronous motor, so as to avoid a problem of low system reliability due to the configuration of the temperature sensor to monitor the temperature of the rotor of the motor.

    [0007] In order to realize the objective described above, a solution is provided as follows.

    [0008] A method of monitoring a temperature of a rotor of a permanent magnet synchronous motor is provided, which includes: acquiring an a-phase line current of a stator of the permanent magnet synchronous motor as a first line current; acquiring a b-phase line current of the stator as a second line current; acquiring a line voltage between the a-phase and the b-phase of the stator; acquiring a rotating speed of the rotor of the permanent magnet synchronous motor; substituting the first line current, the second line current, the line voltage, the rotating speed, an inductance parameter of the permanent magnet synchronous motor and a temperature characteristic equation of a permanent magnet of the rotor into a preset rotor temperature expression, to calculate the temperature of the rotor, wherein, the temperature characteristic equation is acquired by steps of: measuring and recording a current ambient temperature as a first rotor temperature under a condition that the permanent magnet synchronous motor is in a complete cold state; dragging the permanent magnet synchronous motor to a rated rotating speed in an open-circuit state, and measuring a line voltage of the permanent magnet synchronous motor as a first line voltage; running the permanent magnet synchronous motor to rated power, and measuring a temperature of the stator of the permanent magnet synchronous motor as a second rotor temperature after the temperature of the permanent magnet synchronous motor is stable; after measuring the second rotor temperature, making the permanent magnet synchronous motor unloaded and keeping the permanent magnet synchronous motor running at a rated rotating speed, and measuring a line voltage of the permanent magnet synchronous motor as a second line voltage; and deriving the temperature characteristic equation from the first rotor temperature, the first line voltage, the second rotor temperature, the second line voltage and the rated rotating speed.

    [0009] Preferably, the running the permanent magnet synchronous motor to rated power and measuring the temperature of the stator of the permanent magnet synchronous motor as the second rotor temperature after the temperature of the permanent magnet synchronous motor is stable includes: running the permanent magnet synchronous motor at the rated power, and measuring, by a temperature sensor pre-embedded in a stator core of the permanent magnet synchronous motor, a temperature of the stator as the second rotor temperature after the temperature of the permanent magnet synchronous motor is stable.

    [0010] Preferably, the deriving the rotor temperature expression from the first rotor temperature, the first line voltage, the second rotor temperature, the second line voltage and the rated rotating speed includes: calculating a magnetic linkage expression of the permanent magnet of the permanent magnet synchronous motor based on the first rotor temperature, the first line voltage, the second rotor temperature, the second line voltage and the rated rotating speed; calculating magnetic linkage of the permanent magnet at zero degree centigrade according to the magnetic linkage expression; and calculating the rotor temperature expression based on the magnetic linkage expression and the magnetic linkage of the permanent magnet.

    [0011] Preferably, the calculating the rotor temperature expression based on the magnetic linkage expression and the magnetic linkage of the permanent magnet includes: transforming a line voltage expression into a stationary two-phase voltage expression in a stationary two-phase α-β coordinate system; defining an extended back electromotive force expression; substituting the extended back electromotive force expression into the stationary two-phase voltage expression, and acquiring a magnetic linkage expression of the permanent magnet of the rotor by transformation; and substituting the magnetic linkage of the permanent magnet into the magnetic linkage expression of the permanent magnet to acquire the rotor temperature expression.

    [0012] A temperature monitoring system for monitoring a temperature of a rotor of a permanent magnet synchronous motor is provided, which includes: a first acquisition module configured to acquire an a-phase line current of a stator of the permanent magnet synchronous motor as a first line current; a second acquisition module configured to acquire a b-phase line current of the stator as a second line current; a third acquisition module configured to acquire a line voltage between the a-phase and the b-phase of the stator; a fourth acquisition module configure to acquire a rotating speed of the rotor of the permanent magnet synchronous motor; and a calculation and derivation module configured to substitute the first line current, the second line current, the line voltage, the rotating speed, an inductance parameter of the permanent magnet synchronous motor and a temperature characteristic equation of a permanent magnet of the rotor into a preset rotor temperature expression, to calculate the temperature of the rotor, wherein, the calculation and derivation module includes: a first detection unit, a second detection unit and a logic operation unit. The first detection unit is configured to measure and record a current ambient temperature as a first rotor temperature under a condition that the permanent magnet synchronous motor is in a complete cold state; the second detection unit is configured to drag the permanent magnet synchronous motor to a rated rotating speed in an open-circuit state, and measure a line voltage of the permanent magnet synchronous motor as a first line voltage; the first detection unit is further configured to run the permanent magnet synchronous motor to rated power, and measure a temperature of the stator of the permanent magnet synchronous motor as a second rotor temperature after the temperature of the permanent magnet synchronous motor is stable; the second detection unit is further configured to, after the permanent magnet synchronous motor runs at the rated power, make the permanent magnet synchronous motor unloaded and keep the permanent magnet synchronous motor running at a rated rotating speed, and measure a line voltage of the permanent magnet synchronous motor as a second line voltage; and the logic operation unit is configured to calculate the temperature characteristic equation based on the first rotor temperature, the first line voltage, the second rotor temperature, the second line voltage and the rated rotating speed.

    [0013] Preferably, the system for monitoring a temperature of a rotor of a permanent magnet synchronous motor further includes a temperature sensor disposed in a stator core of the permanent magnet synchronous motor and configured to measure the second rotor temperature after the permanent magnet synchronous motor runs at the rated power and the temperature of the permanent magnet synchronous motor is stable.

    [0014] Preferably, the logic operation unit includes: a first calculation subunit configured to calculate a magnetic linkage expression of the permanent magnet of the permanent magnet synchronous motor based on the first rotor temperature, the first line voltage, the second rotor temperature, the second line voltage and the rated rotating speed; a second calculation subunit configured to calculate magnetic linkage of the permanent magnet at zero degree centigrade according to the magnetic linkage expression; and a third calculation subunit configured to calculate the rotor temperature expression based on the magnetic linkage expression and the magnetic linkage of the permanent magnet.

    [0015] Preferably, the third calculation subunit includes: a first transformation circuit configured to transform a line voltage expression into a stationary two-phase voltage expression in a stationary two-phase α-β coordinate system; a definition circuit configured to define an extended back electromotive force expression; a second transformation circuit . configured to substitute the extended back electromotive force expression into the stationary two-phase voltage expression, and acquire a magnetic linkage expression of the permanent magnet of the rotor by transformation; and a third transformation circuit configured to substitute the magnetic linkage of the permanent magnet into the magnetic linkage expression of the permanent magnet to acquire the rotor temperature expression.

    [0016] It can be seen from the technical solution described above that, a method and a system for monitoring a temperature of a rotor of a permanent magnet synchronous motor are provided according to the present disclosure, with the method and the system, the a-phase line current and the b-phase line current of the stator of the permanent magnet synchronous motor are acquired as the first line current and the second line current, respectively, the line voltage between the a-phase and the b-phase of the stator is acquired. Then the first line current, the second line current, the line voltage and the inductance parameter of the permanent magnet synchronous motor and the temperature characteristic equation of the permanent magnet of the rotor are substituted into the preset temperature expression for the permanent magnet of the rotor, to calculate the temperature of the rotor. No temperature sensor is pre-embedded into the rotor to monitor the temperature of the permanent magnet of the rotor in the system and the method, thereby avoiding the problem of low system reliability due to the configuration of the temperature sensor to monitor the temperature of the rotor.

    [0017] In addition, since the temperature of the stator core is not measured in the method and system for monitoring the temperature of the rotor, that is, there is no time delay of thermal conduction between the stator core and the rotor, the temperature of the rotor can be acquired timely, and a magnetic linkage parameter of the permanent magnet can be derived based on the temperature of the rotor, thereby achieving timely protection for the permanent magnet and compensation for the magnetic linkage parameter.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0018] In order to more clearly illustrate the technical solution in the embodiments of the present disclosure or in the conventional technology, in the following, drawings required in the description of the embodiments or the conventional technology will be introduced simply. Obviously, the drawings in the following description are some embodiments of the disclosure. For those skilled in the art, other drawings can also be obtained according to the drawings without any creative work.

    Figure 1 is a flowchart of a method for monitoring a temperature of a rotor of a permanent magnet synchronous motor according to an embodiment of the present disclosure;

    Figure 2 is a flowchart of a derivation process for a temperature characteristic equation of a permanent magnet according to the present disclosure; and

    Figure 3 is a structural diagram of a system for monitoring a temperature of a rotor of a permanent magnet synchronous motor according to another embodiment of the present disclosure.


    DETAILED DESCRIPTION OF EMBODIMENTS



    [0019] Technical solutions according to embodiments of the present disclosure are described clearly and completely hereinafter in conjunction with the drawings in the embodiments of the present disclosure. Apparently, the described embodiments are only some embodiments rather than all the embodiments of the present disclosure. Any other embodiments obtained by those skilled in the art based on the embodiments of the present disclosure without any creative work fall in the scope of protection of the present disclosure.

    First embodiment



    [0020] Figure 1 is a flowchart of a method for monitoring a temperature of a rotor of a permanent magnet synchronous motor according to an embodiment of the present disclosure.

    [0021] A mathematical model of a steady state of a permanent magnet synchronous motor is established first: a current coordinate transformation formula





    [0022] In order to simplify analysis and reduce the dimension of the equation, a mathematical model of the permanent magnet synchronous motor in a dq synchronously rotating coordinate system is adopted. A magnetic linkage equation and a voltage equation of the permanent magnet synchronous motor in the dp synchronously rotating coordinate system may be represented as:



    where id, iq, ud, uq, ψd, ψq, and ψf are components of a stator current, a stator voltage and magnetic linkage in a d axis and in a q axis, and magnetic linkage of a permanent magnet, respectively, Ld and Lq are a direct-axis synchronous inductance and a quadrature-axis synchronous inductance, θe is a position angle of a rotor of a motor, ωe is an electrical angular rate of the motor, and ωe=npωr (np is the number of pole pairs of the motor, and ωr is a mechanical angular rate of the motor), p is a differential operator, and



    [0023] In a steady state, the voltage equation can be simplified as:





    [0024] According to the analysis described above, as shown in Figure 1, the method for monitoring the temperature of the rotor according to the embodiment includes steps S101 to S104.

    [0025] In S101, an a-phase line current and a b-phase line current of the stator are acquired.

    [0026] In the embodiment, the a-phase line current of the stator of the permanent magnet synchronous motor is acquired as a first line current, and the b-phase line current of stator is acquired as a second line current.

    [0027] In S102, a line voltage between the a-phase and the b-phase of the stator is acquired.

    [0028] In S103, a rotating speed of the rotor of the permanent magnet synchronous motor is acquired.

    [0029] In S104, a temperature of the rotor is calculated according to a rotor temperature expression.

    [0030] The first line current, the second line current, the line voltage between the a-phase and the b-phase, the rotating speed of the rotor, an inductance parameter of the permanent magnet synchronous motor and a temperature characteristic equation of a permanent magnet of the rotor are substituted into a preset rotor temperature expression, to calculate a temperature of the rotor.

    [0031] The rotor temperature expression is acquired by steps as follows.

    [0032] Equation (3-3) is transformed into equations (5-7) and (5-8).





    [0033] The equation (5-8) is transformed into a stationary two-phase α-β coordinate system:

    where



    [0034] An extended back electromotive force vector is defined as

    It can be seen from equation (5-10) that the extended back electromotive force vector includes a magnetic linkage component of the permanent magnet of the rotor, therefore, the extended back electromotive force can be calculated according to equation (5-9), and then a magnetic linkage value of the permanent magnet can be derived.

    [0035] A calculation formula (5-11) for the extended back electromotive force can be acquired according to equation (5-9).



    [0036] In equation (5-11), iα and iβ can be acquired by measuring ia and ib and transforming ia and ib according to equation (3-1), vα and vβ are known values outputted from motor vector control, ωe is a measured rotating speed of motor, and Ld and Lq are known inductance parameters of the motor.

    [0037] After the extended back electromotive force is acquired according to equation (5-11), the magnetic linkage of the permanent magnet of the rotor can be extracted according to equation (5-12) as follows.



    [0038] In equation (5-12), id and iq can be acquired by measuring ia and ib and transforming ia and ib according to equation (3-2), ωe is a measured rotating speed of motor, and Ld and Lq are known inductance parameters of the motor.

    [0039] The rotor temperature expression of the permanent magnet of the rotor can be acquired by substituting equation (5-12) into equation (5-6).



    [0040] In equation (5-13) as described above, ia and ib are the first line current and the second line current, respectively.

    [0041] It can be seen from the technical solution described above that, a method and a system for monitoring a temperature of a rotor of a permanent magnet synchronous motor are provided according to the present disclosure. In the method and the system, the a-phase line current and the b-phase line current of the stator of the permanent magnet synchronous motor are acquired as the first line current and the second line current, respectively, and the line voltage between the a-phase and the b-phase of the stator is acquired. Then the first line current, the second line current, the line voltage, the inductance parameter of the permanent magnet synchronous motor and the temperature characteristic equation of the permanent magnet of the rotor are substituted into the preset temperature expression for the permanent magnet of the rotor, to calculate the temperature of the rotor. No temperature sensor is pre-embedded into the rotor to monitor the temperature of the permanent magnet of the rotor in the method, thereby avoiding the problem of low system reliability due to the configuration of the temperature sensor to monitor the temperature of the rotor.

    [0042] In addition, since the temperature of the stator core is not measured in the method and system for monitoring the temperature of the rotor, that is, there is no time delay of thermal conduction between the stator core and the rotor, the temperature of the rotor can be acquired timely. Furthermore, a magnetic linkage parameter of the permanent magnet can be derived based on the temperature of the rotor, thereby achieving timely protection for the permanent magnet and compensation for the magnetic linkage parameter.

    [0043] As shown in Figure 2, the temperature characteristic equation in the embodiment can be acquired by steps as follows.

    [0044] An amplitude value of no-load back electromotive force of the permanent magnet synchronous motor is directly related to a rotating speed of the rotor, as described in the following equation:



    [0045] In equation (5-1), E0, Ua and Uab are respectively an amplitude value of the no-load back electromotive force, a peak value of an a-phase voltage and a peak value of a line voltage of the permanent magnet motor.

    [0046] Therefore, magnetic linkage of a permanent magnet of a rotor corresponding to a certain temperature can be estimated by measuring a line voltage of the motor at a rated rotating speed at the temperature.



    [0047] In S1001, an ambient temperature is recorded under a condition that the permanent magnet synchronous motor is in a cold state.

    [0048] Under a condition that the permanent magnet synchronous motor is in a complete cold state, an ambient temperature of an current environment of the permanent magnet synchronous motor is measured and recorded. Since the permanent magnet synchronous motor is an isothermal body in this case, the ambient temperature is a temperature of the permanent magnet of the rotor.

    [0049] In S1002, a line voltage of the permanent magnet synchronous motor at a rated rotating speed is measured.

    [0050] After the permanent magnet synchronous motor is dragged to a rated rotating speed in an open-circuit state, a line voltage of the permanent magnet synchronous motor is measured as a first line voltage.

    [0051] Temperature rise examination of full power at the rated rotating speed is performed on the permanent magnet motor as a motor, a temperature Th is recorded by a temperature sensor pre-embedded in the stator of the motor after the temperature of the motor is stable.

    [0052] In S1003, a temperature of the rotor of the permanent magnet synchronous motor at rated power is measured.

    [0053] The permanent magnet synchronous motor is run to rated power, a temperature of the stator of the permanent magnet synchronous motor is measured after the temperature of the permanent magnet synchronous motor is stable. In a case that the temperature of the permanent magnet synchronous motor is stable, the entire motor is an isothermal body, and the temperature of the stator is regarded as a second rotor temperature.

    [0054] In S1004, a line voltage of the permanent magnet synchronous motor in a no-load state is measured.

    [0055] after the above step, the permanent magnet synchronous motor is made unloaded and the permanent magnet synchronous motor is kept running at a rated rotating speed, and a line voltage of the permanent magnet synchronous motor is measured as a second line voltage, and a temperature coefficient of the permanent magnet in the permanent magnet motor is derived.





    [0056] In S1005, a temperature characteristic equation of the permanent magnet is calculated.

    [0057] Equations (5-3) and (5-4) are expressions for calculating magnetic linkage of the permanent magnet at a certain temperature based on measurement values.

    [0058] Magnetic linkage ΨfT0 of the permanent magnet of the motor at 0 degree centigrade can be calculated according to equation (5-4), as shown in equation (5-5), and equation (5-4) is further simplified into equation (5-6).





    [0059] Equation (5-6) is the finally obtained temperature characteristic equation of the magnetic linkage of the permanent magnet in the rotor of the permanent magnet motor. It is apparent that a temperature of the permanent magnet can be derived inversely from the magnitude of the magnetic linkage of the permanent magnet in the rotor of the permanent magnet motor at a certain time instant according to equation (5-6).

    Second embodiment



    [0060] Figure 3 is a structural diagram of a system for monitoring a temperature of a rotor of a permanent magnet synchronous motor according to another embodiment of the present disclosure.

    [0061] As shown in Figure 3, the permanent magnet synchronous motor according to the embodiment includes a first acquisition module 10, a second acquisition module 20, a third acquisition module 30 and a calculation and derivation module 40.

    [0062] The first acquisition module 10 is configured to acquire an a-phase line current and a b-phase line current of a stator.

    [0063] The a-phase line current of the stator of the permanent magnet synchronous motor is acquired as a first line current, and the b-phase line current of the stator of the permanent magnet synchronous motor is acquired as a second line current.

    [0064] The second acquisition module 20 is configured to acquire a line voltage between the a-phase and the b-phase of the stator.

    [0065] The third acquisition module 30 is configured to acquire a rotating speed of the rotor of the permanent magnet synchronous motor.

    [0066] The calculation and derivation module 40 is configured to calculate a temperature of the rotor according to a rotor temperature expression.

    [0067] That is, the first line current, the second line current, the line voltage between the a-phase and the b-phase and the rotating speed of the rotor which are acquired in above steps, and an inductance parameter of the permanent magnet synchronous motor and a temperature characteristic equation of the permanent magnet of the rotor are substituted into a preset rotor temperature expression, to calculate the temperature of the rotor.

    [0068] The derivation for the rotor temperature expression and acquisition for the temperature characteristic equation are described in the first embodiment.

    [0069] It can be seen from the technical solution described above that, a system for monitoring a temperature of a rotor of a permanent magnet synchronous motor is provided according to the present disclosure. With the system, the a-phase line current and the b-phase line current of the stator of the permanent magnet synchronous motor are acquired as the first line current and the second line current, respectively, the line voltage between the a-phase and the b-phase of the stator is acquired. Then, the first line current, the second line current, the line voltage and the inductance parameter of the permanent magnet synchronous motor and the temperature characteristic equation of the permanent magnet of the rotor are substituted into the preset temperature expression for the permanent magnet of the rotor, to calculate the temperature of the rotor. No temperature sensor is pre-embedded into the rotor to monitor the temperature of the permanent magnet of the rotor in the system, thereby avoiding the problem of low system reliability due to the configuration of the temperature sensor to monitor the temperature of the rotor.

    [0070] In addition, since the temperature of the stator core is not measured in the method for monitoring the temperature of the rotor, that is, there is no time delay of thermal conduction between the stator core and the rotor, the temperature of the rotor can be acquired timely. Furthermore, a magnetic linkage parameter of the permanent magnet can be derived based on the temperature of the rotor, thereby achieving timely protection for the permanent magnet and compensation for the magnetic linkage parameter.

    [0071] The calculation and derivation module includes: a first detection unit configured to measure and record a current ambient temperature as a first rotor temperature under a condition that the permanent magnet synchronous motor is in a complete cold state; and a second detection unit configured to drag the permanent magnet synchronous motor to a rated rotating speed in an open-circuit state, and measure a line voltage of the permanent magnet synchronous motor as a first line voltage. The first detection unit is further configured to run the permanent magnet synchronous motor to rated power, and measure a temperature of the stator of the permanent magnet synchronous motor as a second rotor temperature after the temperature of the permanent magnet synchronous motor is stable. The second detection unit is further configured to, after the permanent magnet synchronous motor runs at the rated power, make the permanent magnet synchronous motor unloaded and keep the permanent magnet synchronous motor running at a rated rotating speed, and measure a line voltage of the permanent magnet synchronous motor as a second line voltage. The calculation and derivation module includes a logic operation unit configured to calculate the rotor temperature expression based on the first rotor temperature, the first line voltage, the second rotor temperature, the second line voltage and the rated rotating speed.

    [0072] The logic operation unit includes: a first calculation subunit configured to calculate a magnetic linkage expression of the permanent magnet of the permanent magnet synchronous motor based on the first rotor temperature, the first line voltage, the second rotor temperature, the second line voltage and the rated rotating speed; a second calculation subunit configured to calculate magnetic linkage of the permanent magnet at zero degree centigrade according to the magnetic linkage expression; and a third calculation subunit configured to calculate the rotor temperature expression based on the magnetic linkage expression and the magnetic linkage of the permanent magnet.

    [0073] The third calculation subunit includes: a first transformation circuit configured to transform a line voltage expression into a stationary two-phase voltage expression in a stationary two-phase α-β coordinate system; a definition circuit configured to define an extended back electromotive force expression; a second transformation circuit configured to substitute the extended back electromotive force expression into the stationary two-phase voltage expression, and acquire a magnetic linkage expression of the permanent magnet of the rotor by transformation; and a third transformation circuit configured to substitute the magnetic linkage of the permanent magnet into the magnetic linkage expression of the permanent magnet to acquire the rotor temperature expression.

    [0074] In addition, the system further includes a temperature sensor disposed in a stator core of the permanent magnet synchronous motor and configured to measure the second rotor temperature after the permanent magnet synchronous motor runs at the rated power and the temperature of the permanent magnet synchronous motor is stable.


    Claims

    1. A method of monitoring a temperature of a rotor of a permanent magnet synchronous motor, comprising:

    Acquiring (S101), an a-phase line current of a stator of a permanent magnet synchronous motor as a first line current;

    Acquiring (S101), a b-phase line current of the stator as a second line current;

    Acquiring (S102), a line voltage between the a-phase and the b-phase of the stator;

    Acquiring (S103), a rotating speed of a rotor of the permanent magnet synchronous motor;

    Substituting (S104), the first line current, the second line current, the line voltage, the rotating speed, an inductance parameter of the permanent magnet synchronous motor and a temperature characteristic equation of a permanent magnet of the rotor into a preset rotor temperature expression, to calculate the temperature of the rotor,

    characterised in that:
    the temperature characteristic equation is acquired by steps of:

    measuring and recording a current ambient temperature as a first rotor temperature under a condition that the permanent magnet synchronous motor is in a complete cold state (S1001);

    dragging the permanent magnet synchronous motor to a rated rotating speed in an open-circuit state, and measuring a line voltage of the permanent magnet synchronous motor as a first line voltage (S1002);

    running the permanent magnet synchronous motor to rated power, and measuring a temperature of the stator of the permanent magnet synchronous motor as a second rotor temperature after the temperature of the permanent magnet synchronous motor is stable (S1003);

    after measuring the second rotor temperature, making the permanent magnet synchronous motor unloaded and keeping the permanent magnet synchronous motor running at a rated rotating speed, and measuring a line voltage of the permanent magnet synchronous motor as a second line voltage (S1004); and

    deriving the temperature characteristic equation from the first rotor temperature, the first line voltage, the second rotor temperature, the second line voltage and the rated rotating speed (S1005).


     
    2. The method of monitoring a temperature of a rotor of a permanent magnet synchronous motor according to claim 1, wherein the running the permanent magnet synchronous motor to rated power and measuring the temperature of the stator of the permanent magnet synchronous motor as the second rotor temperature after the temperature of the permanent magnet synchronous motor is stable (S1003) comprises:

    running the permanent magnet synchronous motor at the rated power; and

    measuring, by a temperature sensor pre-embedded in a stator core of the permanent magnet synchronous motor, the temperature of the stator as the second rotor temperature after the temperature of the permanent magnet synchronous motor is stable.


     
    3. The method of monitoring a temperature of a rotor of a permanent magnet synchronous motor according to claim 1, wherein the deriving the rotor temperature expression from the first rotor temperature, the first line voltage, the second rotor temperature, the second line voltage and the rated rotating speed (S1005) comprises:

    calculating a magnetic linkage expression of the permanent magnet of the permanent magnet synchronous motor based on the first rotor temperature, the first line voltage, the second rotor temperature, the second line voltage and the rated rotating speed;

    calculating magnetic linkage of the permanent magnet at zero degree centigrade according to the magnetic linkage expression; and

    calculating the rotor temperature expression based on the magnetic linkage expression and the magnetic linkage of the permanent magnet.


     
    4. The method of monitoring a temperature of a rotor of a permanent magnet synchronous motor according to claim 3, the calculating the rotor temperature expression based on the magnetic linkage expression and the magnetic linkage of the permanent magnet comprises:

    transforming a line voltage expression into a stationary two-phase voltage expression in a stationary two-phase α-β coordinate system;

    defining an extended back electromotive force expression;

    substituting the extended back electromotive force expression into the stationary two-phase voltage expression, and acquiring a magnetic linkage expression of the permanent magnet of the rotor by transformation; and

    substituting the magnetic linkage of the permanent magnet into the magnetic linkage expression of the permanent magnet to acquire the rotor temperature expression.


     
    5. A temperature monitoring system for monitoring a temperature of a rotor of a permanent magnet synchronous motor, comprising:

    a first acquisition module (10) configured to acquire an a-phase line current of a stator of a permanent magnet synchronous motor as a first line current;

    a second acquisition module (20) configured to acquire a b-phase line current of the stator as a second line current;

    a third acquisition module (30) configured to acquire a line voltage between the a-phase and the b-phase of the stator;

    a fourth acquisition module configure to acquire a rotating speed of a rotor of the permanent magnet synchronous motor; and

    a calculation and derivation module (40) configured to substitute the first line current, the second line current, the line voltage, the rotating speed, an inductance parameter of the permanent magnet synchronous motor and a temperature characteristic equation of a permanent magnet of the rotor into a preset rotor temperature expression, to calculate the temperature of the rotor,

    characterised in that:
    the calculation and derivation module (40) comprises:

    a first detection unit,

    a second detection unit, and

    a logic operation unit, wherein

    the first detection unit is configured to measure and record a current ambient temperature as a first rotor temperature under a condition that the permanent magnet synchronous motor is in a complete cold state;

    the second detection unit is configured to drag the permanent magnet synchronous motor to a rated rotating speed in an open-circuit state, and measure a line voltage of the permanent magnet synchronous motor as a first line voltage;

    the first detection unit is further configured to run the permanent magnet synchronous motor to rated power, and measure a temperature of the stator of the permanent magnet synchronous motor as a second rotor temperature after the temperature of the permanent magnet synchronous motor is stable;

    the second detection unit is further configured to, after the permanent magnet synchronous motor runs at the rated power, make the permanent magnet synchronous motor unloaded and keep the permanent magnet synchronous motor running at a rated rotating speed, and measure a line voltage of the permanent magnet synchronous motor as a second line voltage; and

    the logic operation unit is configured to calculate the temperature characteristic equation based on the first rotor temperature, the first line voltage, the second rotor temperature, the second line voltage and the rated rotating speed.


     
    6. The temperature monitoring system for monitoring a temperature of a rotor of a permanent magnet synchronous motor according to claim 5, further comprising:
    a temperature sensor disposed in a stator core of the permanent magnet synchronous motor and configured to measure the second rotor temperature after the permanent magnet synchronous motor runs at the rated power and the temperature of the permanent magnet synchronous motor is stable.
     
    7. The temperature monitoring system for monitoring a temperature of a rotor of a permanent magnet synchronous motor according to claim 5, wherein the logic operation unit comprises:

    a first calculation subunit configured to calculate a magnetic linkage expression of the permanent magnet of the permanent magnet synchronous motor based on the first rotor temperature, the first line voltage, the second rotor temperature, the second line voltage and the rated rotating speed;

    a second calculation subunit configured to calculate magnetic linkage of the permanent magnet at zero degree centigrade according to the magnetic linkage expression; and

    a third calculation subunit configured to calculate the rotor temperature expression based on the magnetic linkage expression and the magnetic linkage of the permanent magnet.


     
    8. The system of monitoring a temperature of a rotor of a permanent magnet synchronous motor according to claim 7, wherein the third calculation subunit comprises:

    a first transformation circuit configured to transform a line voltage expression into a stationary two-phase voltage expression in a stationary two-phase α-β coordinate system;

    a definition circuit configured to define an extended back electromotive force expression;

    a second transformation circuit configured to substitute the extended back electromotive force expression into the stationary two-phase voltage expression, and acquire a magnetic linkage expression of the permanent magnet of the rotor by transformation; and

    a third transformation circuit configured to substitute the magnetic linkage of the permanent magnet into the magnetic linkage expression of the permanent magnet to acquire the rotor temperature expression.


     


    Ansprüche

    1. Verfahren zum Überwachen einer Temperatur eines Rotors eines Permanentmagnet-Synchronmotors, das Folgendes beinhaltet:

    Erfassen (S101) eines a-Phasen-Leitungsstroms eines Stators eines Permanentmagnet-Synchronmotors als einen ersten Leitungsstrom;

    Erfassen (S101) eines b-Phasen-Leitungsstroms des Stators als einen zweiten Leitungsstrom;

    Erfassen (S102) einer Leitungsspannung zwischen der a-Phase und der b-Phase des Stators;

    Erfassen (S103) einer Drehzahl eines Rotors des Permanentmagnet-Synchronmotors;

    Ersetzen (S104) des ersten Leitungsstroms, des zweiten Leitungsstroms, der Leitungsspannung, der Drehzahl, eines Induktanzparameters des Permanentmagnet-Synchronmotors und einer Temperatur-Kennlinien-Gleichung eines Permanentmagnets des Rotors durch einen voreingestellten Rotortemperaturausdruck, um die Temperatur des Rotors zu berechnen,

    dadurch gekennzeichnet, dass:
    die Temperatur-Kennlinien-Gleichung durch die folgenden Schritte erfasst wird:

    Messen und Aufzeichnen einer aktuellen Umgebungstemperatur als eine erste Rotortemperatur unter einer Bedingung, dass der Permanentmagnet-Synchronmotor in einem kompletten Kaltzustand (S1001) ist;

    Ziehen des Permanentmagnet-Synchronmotors auf eine Nenndrehzahl im offenen Kreislauf und Messen einer Leitungsspannung des Permanentmagnet-Synchronmotors als eine erste Leitungsspannung (S1002);

    Hochfahren des Permanentmagnet-Synchronmotors auf Nennleistung und Messen einer Temperatur des Stators des Permanentmagnet-Synchronmotors als eine zweite Rotortemperatur, wenn die Temperatur des Permanentmagnet-Synchronmotors stabil ist (S1003);

    Wegnehmen der Last, nach dem Messen der zweiten Rotortemperatur, des Permanentmagnet-Synchronmotors und Laufenlassen des Permanentmagnet-Synchronmotors auf einer Nenndrehzahl und Messen einer Leitungsspannung des Permanentmagnet-Synchronmotors als eine zweite Leitungsspannung (S1004); und

    Ableiten der Temperatur-Kennlinien-Gleichung von der ersten Rotortemperatur, der ersten Leitungsspannung, der zweiten Rotortemperatur, der zweiten Leitungsspannung und der Nenndrehzahl (S1005).


     
    2. Verfahren zum Überwachen einer Temperatur eines Rotors eines Permanentmagnet-Synchronmotors nach Anspruch 1, wobei das Hochfahren des Permanentmagnet-Synchronmotors auf Nennleistung und das Messen der Temperatur des Stators des Permanentmagnet-Synchronmotors als zweite Rotortemperatur, wenn die Temperatur des Permanentmagnet-Synchronmotors stabil ist (S1003), Folgendes beinhaltet:

    Betreiben des Permanentmagnet-Synchronmotors mit der Nennleistung; und

    Messen, mit einem in einem Statorkern des Permanentmagnet-Synchronmotors zuvor eingebetteten Temperatursensor, der Temperatur des Stators als die zweite Rotortemperatur, wenn die Temperatur des Permanentmagnet-Synchronmotors stabil ist.


     
    3. Verfahren zum Überwachen einer Temperatur eines Rotors eines Permanentmagnet-Synchronmotors nach Anspruch 1, wobei das Ableiten des Rotortemperaturausdrucks von der ersten Rotortemperatur, der ersten Leitungsspannung, der zweiten Rotortemperatur, der zweiten Leitungsspannung und der Nenndrehzahl (S1005) Folgendes beinhaltet:

    Berechnen eines Flussverkettungsausdrucks des Permanentmagnets des Permanentmagnet-Synchronmotors auf der Basis der ersten Rotortemperatur, der ersten Leitungsspannung, der zweiten Rotortemperatur, der zweiten Leitungsspannung und der Nenndrehzahl;

    Berechnen einer Flussverkettung des Permanentmagnets bei null Grad Celsius gemäß dem Flussverkettungsausdruck; und

    Berechnen des Rotortemperaturausdrucks auf der Basis des Flussverkettungsausdrucks und der Flussverkettung des Permanentmagnets.


     
    4. Verfahren zum Überwachen einer Temperatur eines Rotors eines Permanentmagnet-Synchronmotors nach Anspruch 3, wobei das Berechnen des Rotortemperaturausdrucks auf der Basis des Flussverkettungsausdrucks und der Flussverkettung des Permanentmagnets Folgendes beinhaltet:

    Umwandeln eines Leitungsspannungsausdrucks in einen stationären Zweiphasen-Spannungsausdruck in einem stationären Zweiphasen-α-β-Koordinatensystem;

    Definieren eines erweiterten Gegenmotorische-Kraft-Ausdrucks;

    Ersetzen des erweiterten Gegenmotorische-Kraft-Ausdrucks in den stationären Zweiphasen-Spannungsausdruck und Erfassen eines Flussverkettungsausdrucks des Permanentmagnets des Rotors durch Umwandlung; und

    Ersetzen der Flussverkettung des Permanentmagnets durch den Flussverkettungsausdruck des Permanentmagnets zum Erfassen des Rotortemperaturausdrucks.


     
    5. Temperaturüberwachungssystem zum Überwachen einer Temperatur eines Rotors eines Permanentmagnet-Synchronmotors, das Folgendes umfasst:

    ein erstes Erfassungsmodul (10), konfiguriert zum Erfassen eines a-Phasen-Leitungsstroms eines Stators eines Permanentmagnet-Synchronmotors als einen ersten Leitungsstrom;

    ein zweites Erfassungsmodul (20), konfiguriert zum Erfassen eines b-Phasen-Leitungsstroms des Stators als einen zweiten Leitungsstrom;

    ein drittes Erfassungsmodul (30), konfiguriert zum Erfassen einer Leitungsspannung zwischen der a-Phase und der b-Phase des Stators;

    ein viertes Erfassungsmodul, konfiguriert zum Erfassen einer Drehzahl eines Rotors des Permanentmagnet-Synchronmotors; und

    ein Rechen- und Ableitungsmodul (40), konfiguriert zum Ersetzen des ersten Leitungsstroms, des zweiten Leitungsstroms, der Leitungsspannung, der Drehzahl, eines Induktanzparameters des Permanentmagnet-Synchronmotors und einer Temperatur-Kennlinien-Gleichung eines Permanentmagnets des Rotors durch einen voreingestellten Rotortemperaturausdruck zum Berechnen der Temperatur des Rotors,

    dadurch gekennzeichnet, dass:
    das Rechen- und Ableitungsmodul (40) Folgendes umfasst:

    eine erste Erkennungseinheit,

    eine zweite Erkennungseinheit, und

    eine Logikbetriebseinheit, wobei

    die erste Erkennungseinheit zum Messen und Aufzeichnen einer aktuellen Umgebungstemperatur als erste Rotortemperatur unter einer Bedingung konfiguriert ist, dass der Permanentmagnet-Synchronmotor in einem kompletten Kaltzustand ist;

    die zweite Erkennungseinheit zum Ziehen des Permanentmagnet-Synchronmotors auf eine Nenndrehzahl im offenen Kreislauf und zum Messen einer Leitungsspannung des Permanentmagnet-Synchronmotors als eine erste Leitungsspannung konfiguriert ist;

    die erste Erkennungseinheit ferner zum Betreiben des Permanentmagnet-Synchronmotors mit Nennleistung und zum Messen einer Temperatur des Stators des Permanentmagnet-Synchronmotors als eine zweite Rotortemperatur konfiguriert ist, wenn die Temperatur des Permanentmagnet-Synchronmotors stabil ist;

    die zweite Erkennungseinheit ferner zum Wegnehmen der Last, wenn der Permanentmagnet-Synchronmotor mit der Nennleistung arbeitet, des Permanentmagnet-Synchronmotors und zum Laufenlassen des Permanentmagnet-Synchronmotors mit einer Nenndrehzahl und zum Messen einer Leitungsspannung des Permanentmagnet-Synchronmotors als eine zweite Leitungsspannung konfiguriert ist; und

    die Logikbetriebseinheit zum Berechnen der Temperatur-Kennlinien-Gleichung auf der Basis der ersten Rotortemperatur, der ersten Leitungsspannung, der zweiten Rotortemperatur, der zweiten Leitungsspannung und der Nenndrehzahl konfiguriert ist.


     
    6. Temperaturüberwachungssystem zum Überwachen einer Temperatur eines Rotors eines Permanentmagnet-Synchronmotors nach Anspruch 5, das ferner Folgendes umfasst:
    einen Temperatursensor, der in einem Statorkern des Permanentmagnet-Synchronmotors angeordnet und zum Messen der zweiten Rotortemperatur konfiguriert ist, wenn der Permanentmagnet-Synchronmotor mit der Nennleistung arbeitet und die Temperatur des Permanentmagnet-Synchronmotors stabil ist.
     
    7. Temperaturüberwachungssystem zum Überwachen einer Temperatur eines Rotors eines Permanentmagnet-Synchronmotors nach Anspruch 5, wobei die Logikbetriebseinheit Folgendes umfasst:

    eine erste Rechensubeinheit, konfiguriert zum Berechnen eines Flussverkettungsausdrucks des Permanentmagnets des Permanentmagnet-Synchronmotors auf der Basis der ersten Rotortemperatur, der ersten Leitungsspannung, der zweiten Rotortemperatur, der zweiten Leitungsspannung und der Nenndrehzahl;

    eine zweite Rechensubeinheit, konfiguriert zum Berechnen der Flussverkettung des Permanentmagnets bei null Grad Celsius gemäß dem Flussverkettungsausdruck; und

    eine dritte Rechensubeinheit, konfiguriert zum Berechnen des Rotortemperaturausdrucks auf der Basis des Flussverkettungsausdrucks und der Flussverkettung des Permanentmagnets.


     
    8. System zum Überwachen einer Temperatur eines Rotors eines Permanentmagnet-Synchronmotors nach Anspruch 7, wobei die dritte Rechensubeinheit Folgendes umfasst:

    eine erste Umwandlungsschaltung, konfiguriert zum Umwandeln eines Leitungsspannungsausdrucks in einen stationären Zweiphasen-Spannungsausdruck in einem stationären Zweiphasen-α-β-Koordinatensystem;

    eine Definitionsschaltung, konfiguriert zum Definieren eines erweiterten Gegenmotorische-Kraft-Ausdrucks;

    eine zweite Umwandlungsschaltung, konfiguriert zum Ersetzen des erweiterten Gegenmotorische-Kraft-Ausdrucks durch den stationären Zweiphasen-Spannungsausdruck und Erfassen eines Flussverkettungsausdrucks des Permanentmagnets des Rotors durch Umwandlung; und

    eine dritte Umwandlungsschaltung, konfiguriert zum Ersetzen der Flussverkettung des Permanentmagnets durch den Flussverkettungsausdruck des Permanentmagnets zum Erfassen des Rotortemperaturausdrucks.


     


    Revendications

    1. Procédé de surveillance d'une température d'un rotor d'un moteur synchrone à aimant permanent, comprenant :

    l'acquisition (S101), d'un courant de ligne de phase a d'un stator d'un moteur synchrone à aimant permanent en tant que premier courant de ligne ;

    l'acquisition (S101), d'un courant de ligne de phase b du stator en tant que second courant de ligne ;

    l'acquisition (S 102), d'une tension de ligne entre la phase a et la phase b du stator ;

    l'acquisition (S103), d'une vitesse de rotation d'un rotor du moteur synchrone à aimant permanent ;

    la substitution (S104), du premier courant de ligne, du second courant de ligne, de la tension de ligne, de la vitesse de rotation, d'un paramètre d'inductance du moteur synchrone à aimant permanent et d'une équation de caractéristique de température d'un aimant permanent du rotor dans une expression de température de rotor prédéfinie, pour calculer la température du rotor,

    caractérisé en ce que :
    l'équation de caractéristique de température est acquise par des étapes de :

    mesure et enregistrement d'une température ambiante courante en tant que première température de rotor lorsque que le moteur synchrone à aimant permanent est complètement froid (S1001)

    montée du moteur synchrone à aimant permanent à une vitesse de rotation nominale dans un état de circuit ouvert, et mesure d'une tension de ligne du moteur synchrone à aimant permanent en tant que première tension de ligne (S 1002) ;

    marche du moteur synchrone à aimant permanent à une puissance nominale, et mesure d'une température du stator du moteur synchrone à aimant permanent en tant que seconde température de rotor une fois que la température du moteur synchrone à aimant permanent est stable (S 1003) ;

    après la mesure de la seconde température de rotor, décharge du moteur synchrone à aimant permanent et maintien du moteur synchrone à aimant permanent à une vitesse de rotation nominale, et mesure d'une tension de ligne du moteur synchrone à aimant permanent en tant que seconde tension de ligne (S 1004) ; et

    dérivée de l'équation de caractéristique de température à partir de la première température de rotor, de la première tension de ligne, de la seconde température de rotor, de la seconde tension de ligne et de la vitesse de rotation nominale (S 1005).


     
    2. Procédé de surveillance d'une température d'un rotor d'un moteur synchrone à aimant permanent selon la revendication 1, dans lequel le fonctionnement du moteur synchrone à aimant permanent à une puissance nominale et la mesure de la température du stator du moteur synchrone à aimant permanent en tant que seconde température de rotor une fois que la température du moteur synchrone à aimant permanent est stable (S 1003) comprend :

    la marche du moteur synchrone à aimant permanent à la puissance nominale ; et

    la mesure, par un capteur de température préincorporé dans un noyau statorique du moteur synchrone à aimant permanent, de la température du stator en tant que seconde température de rotor une fois que la température du moteur synchrone à aimant permanent est stable.


     
    3. Procédé de surveillance d'une température d'un rotor d'un moteur synchrone à aimant permanent selon la revendication 1, dans lequel la dérivée de l'expression de température de rotor à partir de la première température de rotor, de la première tension de ligne, de la seconde température de rotor, de la seconde tension de ligne et de la vitesse de rotation nominale (S 1005) comprend :

    le calcul d'une expression de couplage magnétique de l'aimant permanent du moteur synchrone à aimant permanent sur la base de la première température de rotor, de la première tension de ligne, de la seconde température de rotor, de la seconde tension de ligne et de la vitesse de rotation nominale ;

    le calcul du couplage magnétique de l'aimant permanent à zéro degré centigrade conformément à l'expression de couplage magnétique ; et

    le calcul de l'expression de température de rotor sur la base de l'expression de couplage magnétique et du couplage magnétique de l'aimant permanent.


     
    4. Procédé de surveillance d'une température d'un rotor d'un moteur synchrone à aimant permanent selon la revendication 3, le calcul de l'expression de la température de rotor basé sur l'expression de couplage magnétique et le couplage magnétique de l'aimant permanent comprenant :

    la transformation d'une expression de tension de ligne en une expression de tension biphasée stationnaire dans un système de coordonnées α-β biphasé stationnaire ;

    la définition d'une expression de force contre-électromotrice étendue ;

    la substitution de l'expression de force contre-électromotrice étendue dans l'expression de tension biphasée stationnaire, et l'acquisition d'une expression de couplage magnétique de l'aimant permanent du rotor par transformation ; et

    la substitution du couplage magnétique de l'aimant permanent dans l'expression de couplage magnétique de l'aimant permanent pour acquérir l'expression de température de rotor.


     
    5. Système de surveillance de température pour surveiller une température d'un rotor d'un moteur synchrone à aimant permanent, comprenant :

    un premier module d'acquisition (10) configuré pour acquérir un courant de ligne de phase a d'un stator d'un moteur synchrone à aimant permanent en tant que premier courant de ligne ;

    un deuxième module d'acquisition (20) configuré pour acquérir un courant de ligne de phase b du stator en tant que second courant de ligne ;

    un troisième module d'acquisition (30) configuré pour acquérir une tension de ligne entre la phase a et la phase b du stator ;

    un quatrième module d'acquisition configuré pour acquérir une vitesse de rotation d'un rotor du moteur synchrone à aimant permanent ; et

    un module de calcul et de dérivée (40) configuré pour substituer le premier courant de ligne, le second courant de ligne, la tension de ligne, la vitesse de rotation, un paramètre d'inductance du moteur synchrone à aimant permanent et une équation de caractéristique de température d'un aimant permanent du rotor dans une expression de température de rotor prédéfinie, pour calculer la température du rotor,

    caractérisé en ce que :
    le module de calcul et de dérivée (40) comprend :

    une première unité de détection,

    une seconde unité de détection, et

    une unité d'opération logique, dans lequel

    la première unité de détection est configurée pour mesurer et enregistrer une température ambiante courante en tant que première température de rotor lorsque le moteur synchrone à aimant permanent est complètement froid ;

    la seconde unité de détection est configurée pour monter le moteur synchrone à aimant permanent à une vitesse de rotation nominale dans un état de circuit ouvert, et mesurer une tension de ligne du moteur synchrone à aimant permanent en tant que première tension de ligne ;

    la première unité de détection est configurée en outre pour faire fonctionner le moteur synchrone à aimant permanent à une puissance nominale, et mesurer une température du stator du moteur synchrone à aimant permanent en tant que seconde température de rotor une fois que la température du moteur synchrone à aimant permanent est stable ;

    la seconde unité de détection est configurée en outre pour, après que le moteur synchrone à aimant permanent tourne à la puissance nominale, décharger le moteur synchrone à aimant permanent et maintenir le moteur synchrone à aimant permanent à une vitesse de rotation nominale, et mesurer une tension de ligne du moteur synchrone à aimant permanent en tant que seconde tension de ligne ; et

    l'unité d'opération logique est configurée pour calculer l'équation de caractéristique de température sur la base de la première température de rotor, la première tension de ligne, la seconde température de rotor, la seconde tension de ligne et la vitesse de rotation nominale.


     
    6. Système de surveillance de température pour surveiller une température d'un rotor d'un moteur synchrone à aimant permanent selon la revendication 5, comprenant en outre :
    un capteur de dispositif disposé dans un noyau statorique du moteur synchrone à aimant permanent et configuré pour mesurer la seconde température de rotor une fois que le moteur synchrone à aimant permanent tourne à la puissance nominale et la température du moteur synchrone à aimant permanent est stable.
     
    7. Système de surveillance de température pour surveiller une température d'un rotor d'un moteur synchrone à aimant permanent selon la revendication 5, dans lequel l'unité d'opération logique comprend :

    une première sous-unité de calcul configurée pour calculer une expression de couplage magnétique de l'aimant permanent du moteur synchrone à aimant permanent sur la base de la première température de rotor, la première tension de ligne, la seconde température de rotor, la seconde tension de ligne et la vitesse de rotation nominale ;

    une deuxième sous-unité de calcul configurée pour calculer le couplage magnétique de l'aimant permanent à zéro degré centigrade conformément à l'expression de couplage magnétique ; et

    une troisième sous-unité de calcul configurée pour calculer l'expression de la température de rotor sur la base de l'expression de couplage magnétique et du couplage magnétique de l'aimant permanent.


     
    8. Système de surveillance de température d'un rotor d'un moteur synchrone à aimant permanent selon la revendication 7, dans lequel la troisième sous-unité de calcul comprend :

    un premier circuit de transformation pour transformer une expression de tension de ligne en une expression de tension biphasée stationnaire dans un système de coordonnées α-β biphasé stationnaire ;

    un circuit de définition configuré pour définir une expression de force contre-électromotrice étendue ;

    un deuxième circuit de transformation configuré pour substituer l'expression de force contre-électromotrice étendue dans l'expression de tension biphasée stationnaire, et acquérir une expression de couplage magnétique de l'aimant permanent du rotor par transformation ; et

    un troisième circuit de transformation configuré pour substituer le couplage magnétique de l'aimant permanent dans l'expression de couplage magnétique de l'aimant permanent pour acquérir l'expression de température de rotor.


     




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    Cited references

    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description