Technical Field
[0001] The present invention relates to an elevator control system.
Background Art
[0002] The main circuit of an elevator is provided with a converter converting an AC power
to a DC power, a capacitor smoothing the converter output having voltage ripples into
a smooth DC voltage, and an inverter converting the DC voltage to an arbitrary AC
voltage using power semiconductor elements. The power semiconductor elements are generally
composed of voltage-driven semiconductors such as IGBTs. Hence, a gate power source
is necessary for driving the elements by switching their gate voltage between positive
and negative.
[0003] Except when the elevator operates, the gate voltages are switched to negative for
preventing the power semiconductor elements from malfunctioning. However, when the
main power supply of the elevator is turned off, the outputs of the gate power source
are also lost. This does not allow the gates to be negatively biased; thus, unless
the voltage of the main circuit capacitor is discharged prior to the output loss of
the gate power source, malfunctions of the gates could cause the semiconductor elements
to form a bus short circuit.
[0004] A conventional elevator control system is known, as described in JP H06-9164 A, that
includes an inverter for converting a DC voltage smoothed by a capacitor to an arbitrary
AC voltage to control a motor for driving the elevator, a regeneration power dissipation
resistor for dissipating a regeneration power generated in a motor regeneration operation
through a regeneration current conduction element, and a charging circuit for charging
the capacitor in advance, and further includes a voltage comparison circuit for sending
an output when the capacitor voltage is larger than the output voltage of the charging
circuit, and a charge storage capacitor for supplying, when the power supply is interrupted,
stored electric charges as power to the voltage comparison circuit whose output makes
conductive the regeneration current conduction element. In the conventional elevator
control system, the capacitor is forcibly discharged through the regeneration power
dissipation circuit when the power supply is interrupted, which realizes the forced
discharge of the capacitor in a simple manner.
[0005] JP 2005 162442 A discloses an elevator control system comprising a converter that converts an electric
power from an AC power supply to a DC power using semiconductor elements; a capacitor
that smoothes the DC power; an inverter that converts the DC power to an arbitrary
AC power using switching elements and drives a motor moving an elevator car; a control
means that performs on-off control of the switching elements; a control power-source
means that generates a DC power on the basis of the AC power supply and supplies the
DC power to the control means; a rechargeable battery that supplies a DC power to
the control power-source means when the AC power supply is lost; a first voltage detection
means that detects a value of a first voltage being the output of the control power-source
means; a first determination means that determines whether or not the first voltage
value is a first threshold value or smaller; and a supply means that supplies the
DC power from the rechargeable battery to the control means when the first voltage
value becomes the first threshold value or smaller.
Disclosure of Invention
Problem to be Solved by the Invention
[0006] However, the conventional elevator control system has a problem that when the main
power supply is lost, it is not reliably guaranteed that before the output of a control
power source for controlling the semiconductor elements included in the inverter is
lost, electric charges stored in the capacitor smoothing the converter output voltage
is discharged.
[0007] The present invention is made to solve the problem and aims to obtain an elevator
control system that can appropriately control, when the main power supply is lost,
the semiconductor elements by supplying a power to a control means controlling the
semiconductor elements.
Means for Solving Problem
[0008] An elevator control system according to the present invention comprises the features
mentioned in claim 1.
[0009] In the elevator control system according to the present invention, the first determination
means determines whether or not the first voltage value of the control power-source
means is the first threshold value or smaller; and the supply means supplies an electric
power from the rechargeable battery to the control means when the first voltage value
becomes the first threshold value or smaller. Therefore, even when the output voltage
of the control power-source means drops due to a power interruption or the like, the
electric power can be continuously supplied to the control means from the rechargeable
battery so that the switching elements can be appropriately controlled by the control
means.
[0010] Further, in the elevator control system according to the present invention, the supply
means supplies the dc power from the rechargeable battery to the control means also
when the second voltage value is larger than the second threshold value. Therefore,
only in a case where a large current could flow due to power lines short-circuited
by the switching elements of the inverter, the supply means is allowed to supply the
electric power from the rechargeable battery to the control means, which thereby can
reduce the battery capacity.
[0011] In the elevator control system according to the present invention, it is preferable
that the control power-source means includes, at least, a first and a second control
power-source means whose outputs are connected in parallel to each other, wherein
the first control power-source means supplies a dc voltage to the control means, and
the supply means supplies a dc voltage from the second control power-source means
to the control means when the first voltage value becomes the first threshold value
or smaller.
[0012] According to the elevator control system, an electric power can be supplied to the
control means from the second control power-source means even when the first control
power-source means fails, thereby enhancing the control power-source means' reliability
against failure.
[0013] In the elevator control system according to the present invention, it is preferable
that the output voltage of the second control power-source means is lower than that
of the first control power-source means.
[0014] According to the elevator control system, when the first control power-source means
operates normally, an electric power is supplied to the control means only from the
first control power-source means but is not supplied from the second control power-source
means. When the output voltage of the second control power-source means becomes higher
than that of the first control power-source means, the second control power-source
means supplies the electric power to the control means, which thereby allows the second
control power-source means to have a reduced capacity.
[0015] In the elevator control system according to the present invention, it is preferable
that the first control power-source means generates a first positive bias voltage
for turning on the switching elements and a first negative bias voltage for turning
off the switching elements, and the second control power-source means generates only
a second negative bias voltage for turning off the switching elements.
[0016] In the elevator control system, the first and second control power-source means generate
the negative bias voltages. Therefore, even when the first control power-source means
fails, the switching elements can be reliably turned off by the negative bias voltage
generated from the second control power-source means. Furthermore, the second control
power-source means can be simplified.
[0017] In the elevator control system according to the present invention, it is preferable
that the switching elements constitute an upper arm and a lower arm, and the switching
elements of the lower arm are turned off by the second negative bias voltage. In the
elevator control system, because a duplex system is provided for generating the negative
bias voltage for the switching elements constituting the lower arm of the inverter,
the whole inverter can be reliably turned off even when the first control power-source
means fails. Furthermore, the second control power-source means can be further simplified.
[0018] In the elevator control system according to the present invention, it is preferable
that the second control power-source means generates a single output of a second negative
bias voltage which is always connected to one of the first control power-source means
outputs supplied to the plurality of switching elements of the lower arm, and application
means are provided that apply the single output of the second negative bias voltage
to the rest of the lower arm switching elements when the first determination means
determines that the first voltage value is the first threshold value or smaller. This
provides a duplex system. Therefore, even when the first control power-source means
fails, the whole inverter can be reliably turned off by turning off the switching
element of the lower arm. Thus, it suffices that the second control power-source means
generates the single output of the negative bias voltage, thereby allowing the second
control power-source means to be further simplified.
Effect of the Invention
[0019] When losing the main power supply, an elevator control system according to the present
invention can supply an electric power to the control means controlling switching
elements such as an inverter, so that the control means can appropriately control
the switching elements.
Brief Description of the Drawings
[0020]
Fig. 1 is an overall diagram of an elevator of an embodiment according to the present
invention;
Fig. 2 is an inner configuration view of a gate power source shown in Fig. 1;
Fig. 3 is an overall diagram of an elevator of another embodiment according to the
present invention;
Fig. 4 is an overall diagram of an elevator of another embodiment according to the
present invention;
Fig. 5 is an inner connection diagram showing a first and second gate power-source
circuits in Fig. 4;
Fig. 6 is an inner connection diagram showing another first and second gate power-source
circuits;
Fig. 7 is an inner connection diagram showing another first and second gate power-source
circuits; and
Fig. 8 is an inner connection diagram showing another first and second gate power-source
circuits.
Numerals
[0021]
- 9
- car
- 11
- motor
- 20
- three-phase AC power supply
- 24
- converter
- 26
- capacitor
- 30
- inverter
- 31
- semiconductor element
- 50
- gate power source
- 52
- rechargeable battery
- 60
- gate drive circuit
- 61
- first voltage detection unit
- 81
- first determination unit
- 162
- second voltage detection unit
- 182
- second determination unit
- Se
- supply switch
Best Modes for Carrying Out the Invention
Embodiment 1
[0022] An embodiment according to the present invention will be explained using Fig. 1 and
Fig. 2. Fig. 1 is an overall diagram of an elevator of the embodiment according to
the present invention, and Fig. 2 is an inner configuration view of a gate power source
shown in Fig. 1. In Fig. 1, the elevator is configured so that an end of a counter
weight 3 is connected to one end of a rope 5, the other end of the rope 5 is connected
to a car 9, the rope 5 is in contact with a groove of a traction machine sheave 7,
so that the car 9 is moved upward and downward by a motor 11 rotating the traction
machine sheave 7.
[0023] An elevator control system includes a main power supply switch S1 being normally
open for a three-phase AC power supply 22, a converter 24 converting to DC voltage
with ripples through a normally open contact 22 of an electromagnetic switch, a capacitor
26 smoothing the ripples of the DC voltage, an inverter 30 including semiconductor
elements 31 converting the DC voltage to an arbitrary AC voltage to drive the motor
11, and a gate drive circuit 60 performing on-off control of semiconductor switching
elements 31 in the inverter 30. The capacitor 26 is charged through the main power
supply switch S1, and is discharged through a charge-discharge circuit 35 connected
to both ends of the capacitor 26.
[0024] A gate power source 50 is provided that serves, similarly through the main power
supply switch S1, as a dc power source for the gate drive circuit 60, and the gate
power-source circuit 50 is connected to a backup rechargeable battery 52 through a
supply switch Se. An elevator controller 70 is also provided that generates control
command signals for controlling the gate drive circuit 60 and the charge-discharge
circuit 35.
[0025] There are also provided a first voltage detector 61 that detects a first voltage
value, i.e. the output voltage of the gate power-source circuit 50, and a first determination
unit 83 that determines whether or not the detected first voltage value is a first
threshold value or smaller, and closes the supply switch Se having been opened if
the detected value is the first threshold value or smaller, to supply an electric
power from the rechargeable battery 52 to the gate drive circuit 60.
[0026] In the gate power-source circuit in Fig. 2, a diode 54 connected to an end of the
supply switch Se is connected to an input end of a DC-DC converter 58, and the main
power supply switch S1 is connected to an input of an AC-DC converter 52. The output
of the AC-DC converter 52 is connected to the input end of the DC-DC converter 58
through a diode 56 and to the other input end of the DC-DC converter 58. The gate
power source 50 is configured in a manner that in a condition that the supply switch
Se is closed, an electric power is supplied to the DC-DC converter 58 from a power
source having a higher voltage, out of the AC-DC converter 52 and the rechargeable
battery 52.
[0027] The operation of the elevator control system thus configured will be explained using
Fig. 1 and Fig. 2.
< Normal Operation>
[0028] When the main power supply switch S1 is closed and then the normally open contact
22 having been opened are closed, the AC power-supply voltage is inputted to the gate
power source 50, so that a DC voltage is supplied to the gate drive circuit 60. Meanwhile,
from the three-phase AC power supply, the converter 24 produces a DC power to be inputted
to the inverter 30. The gate drive circuit 60 controls the inverter 30 in accordance
with command signals from the elevator controller 70 to halt or drive the motor 11.
<Operation at Occurrence of Power Outage >
[0029] When a power outage occurs, the main power supply switch S1 and the normally open
contact 22 having been closed are opened so that charges in the capacitor 26 are discharged
through the charge-discharge circuit 35. Meanwhile, the output voltage of the gate
power-source circuit 50 drops. The output voltage, i.e. a first voltage value, is
detected by a first voltage detection unit 80 to be inputted to the first determination
unit 83. The determination unit 83 determines whether or not the first voltage value
is the first threshold value or smaller, and if the first threshold value or smaller,
the determination unit closes the supply switch Se having been open to supply an electric
power from the rechargeable battery 52 to the gate drive circuit 60. Thus, because
the gate drive circuit 60 can be normally controlled even when a power outage occurs,
the switching elements 31 in the inverter 30 can also be controlled.
[0030] The elevator control system according to the above-described embodiment includes
the converter 24 that converts an electric power from the three-phase AC power supply
20 to a DC power using semiconductor elements, the capacitor 26 that smoothes the
DC power, the inverter 30 that converts, using the semiconductor elements 31, the
DC power to an arbitrary AC power to drive the motor 11 moving the elevator the car
9, the gate drive circuit 60 that serves as a control means to control the switching
elements 31, the gate power-source circuit 50 that serves as a control power-source
means to produce a dc power on the basis of the AC power supply 22, and to supply
the dc power to the gate drive circuit 60, the rechargeable battery 52 that supplies
a dc power to the gate power-source circuit 50 when the AC power supply is lost, the
first voltage detection unit 80 that detects the first voltage value, i.e. the output
of the gate power-source circuit 50, the first determination unit 83 that determines
whether or not the first voltage value is the first threshold value or smaller, and
the supply switch Se that serves as a supply means to supply the dc power from the
rechargeable battery 52 to the gate drive circuit 60 when the first voltage value
is the first threshold value or smaller.
[0031] According to the elevator control system, the determination unit 83 determines whether
or not the first voltage value of the gate power-source circuit 50 is the first threshold
value or smaller, and if the first threshold value or smaller, the determination unit
closes the supply switch Se having been open, to supply an electric power from the
rechargeable battery 52 to the gate drive circuit 60. Thus, because the electric power
can be continuously supplied to the gate drive circuit 60 from the rechargeable battery
52 even when the output voltage of the gate power-source circuit 50 drops due to a
power outage or the like, the switching elements 31 can be appropriately controlled
by the gate drive circuit 60.
Embodiment 2
[0032] Another embodiment according to the present invention will be explained, using Fig.
3. Fig. 3 is an overall diagram of an elevator of another embodiment according to
the present invention. In Fig. 3, the same numerals as those in Fig. 1 designate the
same components, whose explanations will be omitted.
[0033] In Fig. 3, an elevator control system is configured such that a second voltage detector
180 detects a second voltage value across the capacitor 26, and a second determination
unit 183 closes the supply switch Se having been open, to supply an electric power
from the rechargeable battery 52 to the gate drive circuit 60 in a condition that
the first voltage value is the first threshold value or smaller and the second voltage
value is larger than a second threshold value.
[0034] Under normal conditions, the elevator control system configured as described above
operates in the same manner as that of Embodiment 1.
<Operation at Occurrence of Power Outage >
[0035] When a power outage occurs, the main power supply switch S1 and the normally open
contact 22 having been closed are opened so that charges in the capacitor 26 are discharged
through the charge-discharge circuit 35. Meanwhile, the output voltage of the gate
power-source circuit 50 drops. The output voltage, i.e. the first voltage value, and
the voltage across the capacitor 26 are detected and inputted to the second determination
unit 183 by the first voltage detection unit 80 and the second voltage detector 180,
respectively. The second determination unit 183 determines whether or not the first
voltage value is the first threshold value or smaller and determines whether or not
the second voltage value is larger than the second threshold value. Then, if the first
voltage value is the first threshold value or smaller and the second voltage value
is larger than the second threshold value, the second determination unit closes the
switch S2 having been opened, to supply an electric power from the rechargeable battery
52 to the gate drive circuit 60. This enables the gate drive circuit 60 to be normally
controlled even when a power outage occurs and to be supplied with an electric power,
taking the magnitude of a short circuit current into account, when the voltage across
the capacitor 26 is larger than the second threshold value.
[0036] An elevator control system according to the above-described embodiment preferably
includes the charge-discharge circuit 35 discharging electric charges in the capacitor
26 in response to loss of the three-phase AC power supply 20, the second voltage detection
unit 180 detecting the second voltage value of the capacitor 26, the second determination
unit 183 determining whether or not the second voltage value is larger than the second
threshold value, and the supply switch Se supplying an electric power to the gate
drive circuit 60 from the rechargeable battery 52 when the first voltage value is
the first threshold value or smaller and the second voltage value is larger than the
second threshold value. That is, because the electric power is supplied to the gate
drive circuit 60 from the rechargeable battery 52 only when the voltage value of the
capacitor 26 is larger than the second threshold value, the capacity of the battery
52 can be reduced.
Embodiment 3
[0037] Another embodiment according to the present invention will be explained using Fig.
4 and Fig. 5. Fig. 4 is an overall diagram of an elevator of another embodiment according
to the present invention; and Fig. 5 is an inner connection diagram of a first and
second gate power-source circuits in Fig. 4. In Fig. 4, the same numerals as those
in Fig. 1 donate the same components.
[0038] In Embodiments 1 and 2, one gate power-source circuit 50 is provided; however, in
this embodiment, a first gate power-source circuit 150 and a second gate power-source
circuit 250 are provided, as shown in Fig.4, which serve as a duplex system. The inverter
30 has an upper arm 32 and a lower arm 34 which include the switching elements 31:
the upper arm 32 includes switching elements 31uu, 32uv, and 31uw, and the lower arm
34 includes switching element s31du, 31dv, and 31dw.
[0039] A voltage monitoring unit 200 is configured to detect output voltages of the first
and second gate power-source circuits 150 and 250 and to generate an isolation signal
for isolating the gate drive circuit 60 when the two output voltage values drop below
predetermined threshold values.
[0040] In Fig. 5, each of the first and second gate power-source circuits 150 and 250 operates
in a flyback manner and has six power output components for driving the six switching
elements 31 of the inverter 30. In the first gate power-source circuit 150, a voltage
is applied to a capacitor 154 from the three-phase AC power supply through a full-wave
rectifying bridge 152. Both ends of the capacitor 154 are connected to the primary
winding of a transformer 158 through a switching semiconductor element 156. The first
power output components are provided with twelve windings in pairs thereof, and each
pair is for generating positive and negative bias voltages to turn on and off the
switching elements 31 of the upper arm 32 and the lower arm 34.
[0041] In the first power output component, one end of the secondary winding of the transformer
158 is connected to one end of a diode D11 (D12 through D16), the other end of the
secondary winding is connected to one end of a diode D21 (D22 through D26), and a
center point of the secondary winding is connected to one end of each of two smoothing
capacitors C11 (C12 through C16) and C21 (C22 through C26). The other end of the smoothing
capacitor C11 (C12 through C16) is connected to the other end of the diode D11 (D12
through D16), and the other end of the capacitor C21 (C22 through C26) is connected
to the diode D21 (D22 through D26).
[0042] In the second gate power-source circuit 250, a voltage is applied to a capacitor
254 from the battery 52. Both ends of the capacitor 254 are connected to the primary
winding of the transformer 158 through a switching semiconductor element 256. The
second power output components are provided with twelve windings in pairs thereof,
and each pair is for generating positive and negative bias voltages to turn on and
off the switching elements 31 included in the inverter 30.
[0043] In the second power output component, one end of the secondary winding of a transformer
258 is connected to one end of a diode D31 (D32 through D36), the other end of the
secondary winding is connected to one end of a diode D41 (D42 through 426), and a
center point of the secondary winding is connected to one end of each of two smoothing
capacitors C31 (C32 through C36) and C41 (C42 through C46). The other end of the smoothing
capacitor C31 (C32 through C36) is connected to the other end of the diode D31 (D32
through D36), and the other end of the capacitor C41 (C42 through C46) is connected
to the diode D41 (D42 through D46).
[0044] Furthermore, the outputs of the second power output components are always connected
to the first power output components in parallel.
[0045] When V1-1 and V2-1 denote the positive bias voltage and the negative bias voltage
of the first gate power-source circuit 150, respectively, and V1-2 and V2-2 denote
the positive bias voltage and the negative bias voltage of the second gate power-source
circuit 250, respectively, the absolute values of the respective output voltages have
relations below.
The above-described relations prevent the output current of the second gate power-source
circuit 250 from flowing under a normal condition where the first gate power-source
circuit 150 does not fail.
[0046] Operations of the elevator control system thus configured will be explained using
Fig. 4 and Fig. 5.
<Normal operation>
[0047] When the main power supply switch S1 is closed and then the normally open contact
22 having been opened are closed, the AC power-supply voltage is inputted to the first
gate power-source circuit 150, so that a DC voltage is supplied to the gate drive
circuit 60.
[0048] Meanwhile, the converter 24 produces from the three-phase AC power supply, a DC power
to be inputted to the inverter 30. The first gate drive circuit 150 controls the inverter
30 in accordance with command signals from the elevator controller 70 to halt or drive
the motor 11.
<Operation at Abnormality>
[0049] When the voltages of the first gate power-source circuit 150 drop, for some reason,
below the output voltages of the second gate power-source circuit 250, the outputs
of the second gate power-source circuit 250 are inputted as gate signals to the switching
elements 31 of the inverter 31. Therefore, even when the first gate power-source circuit
150 fails, the inverter 30 can be driven through the gate drive circuit 60 by the
second gate power-source circuit 250. Furthermore, when a power outage occurs, the
rechargeable battery 52 serves an input source, so that the inverter 30 can be driven
through the gate drive circuit 60 fed by the second gate power-source circuit 250.
Embodiment 4
[0050] In Embodiment 3, both of the first gate power-source circuit 150 and the second gate
power-source circuit 250 generate the positive bias voltages and the negative bias
voltages in order to configure, as shown in Fig. 5, a duplex gate-power-source circuit
system; however, in this embodiment, a second gate power-source circuit 1250 is configured,
as shown in Fig. 6, to generate only the negative bias voltage without generating
the positive bias voltage, and the respective outputs of the negative bias voltage,
i.e. the outputs of the second power output components, are always connected in parallel
to those of the corresponding first power output components.
[0051] In the elevator control system thus configured, a duplex system ensures the negative
bias voltage. By the duplex system, the switching elements 31 can be reliably turned
off, because the negative bias voltage can be applied to the switching elements 31
in the inverter 30 from the second gate power-source circuit 1250 even when the first
gate power-source circuit 150 cannot generate the negative bias voltage.
[0052] According to the duplex system, the elevator control system of this embodiment can
be simplified in comparison to that of Embodiment 3, because positive-bias-voltage
generation parts can be eliminated in the second gate power-source circuit 1250.
Embodiment 5
[0053] In Embodiment 4, the duplex system for gate power-source circuit is configured only
for the negative bias voltage, as shown in Fig. 6; however, in this embodiment, a
second gate power-source circuit 2250 is configured, as shown in Fig. 7, to generate
only three outputs of the negative bias voltage applied to the switching elements
31 of the lower arm 34 in the inverter. The three outputs of the negative bias voltage,
i.e. the outputs of the second power output components, are always connected in parallel
to those of the corresponding first power output components.
[0054] In the elevator control system thus configured, a duplex system ensures the negative
bias voltage for the switching elements 31 of the lower arm 34 in the inverter 30;
thus, even when a failure occurs in a negative-bias-voltage-generation part of the
first gate power-source circuit 150, the corresponding output of the negative bias
voltage can be applied from the second gate power-source circuit 2250 to the switching
elements 31 of the lower arm 34, thereby preventing the switching elements 31 from
malfunctioning.
[0055] In this embodiment, because three negative-bias-voltage-generation parts can be eliminated
that are for the switching elements 31 of the upper arm 32 in the inverter 30, the
second gate power-source circuit 2250 can be simply configured in comparison to that
in Embodiment 4.
Embodiment 6
[0056] In Embodiment 5, the second gate power-source circuit 2250 generates, as shown in
Fig. 7, only three outputs of the negative bias voltage for the switching elements
31 of the lower arm 34 in the inverter 30, and the three outputs of negative bias
voltage, i.e. the outputs of the second power output components, are always connected
in parallel to those of the corresponding first power output components; however,
in this embodiment, a second gate power-source circuit 3250 is configured, as shown
in Fig. 8, to generate only one output of the negative bias voltage applied to the
switching element 31 of the lower arm 34 in the inverter 30, and the one output of
the negative bias voltage is always connected in parallel to the negative bias voltage
output of the first gate power-source circuit 150. Then, the one output of the negative
bias voltage is connected through switches S1-S4 to the rest of the negative bias
voltage outputs to be inputted to two switching elements 31 of the lower arm 34 in
the inverter 30.
[0057] According to the elevator control system thus configured, when a failure is detected
in generation parts generating the rest of the negative bias voltages in the first
gate power-source circuit 150, the switches S1-S4 are turned on to apply the negative
bias voltage from the second gate power-source circuit 3250 to the switching elements
31 of the lower arm 34, thereby preventing the switching elements 31 from malfunctioning.
[0058] In this embodiment, because two negative-bias-voltage-generation parts can be eliminated
that are for the switching elements 31 of the lower arm 34 in the inverter 30, the
second gate power-source circuit can be simplified in comparison to that in Embodiment
5.
[0059] In addition, the switching elements 31 in the inverter 30 used in Embodiments 1 to
6 may be made up of a silicon semiconductor, however it is preferable that the switching
elements are made up of a wide band gap semiconductor having a band gap wider than
silicon. A wide band gap semiconductor includes, for example, silicon carbide, gallium
nitride material, and diamond.
[0060] The switching elements 31 made up of such a wide band gap semiconductor have a high
performance in withstanding voltage and have a high tolerance for current density,
therefore the switching elements 31 can be miniaturized; thus, by using the miniaturized
switching elements 31, an inverter using the miniaturized switching elements can be
made smaller. In addition, even when the switching elements 31 in the inverters 30
of Embodiments 1 through 6 are made up of a wide band gap semiconductor, the switching
elements 31 can be appropriately controlled even if the AC power supply is lost.
Industrial Applicability
[0061] The present invention is applicable to elevator control systems.
1. An elevator control system comprising:
a converter (24) that converts an electric power from an AC power supply (20) to a
DC power using semiconductor elements;
a capacitor (26) that smoothes the DC power;
an inverter (30) that converts the DC power to an arbitrary AC power using switching
elements (31) and drives a motor (11) moving an elevator car (9);
a control means (60) that performs on-off control of the switching elements;
a control power-source means (50) that generates a DC power on the basis of the AC
power supply and supplies the DC power to the control means;
a rechargeable battery (52) that supplies a DC power to the control power-source means
when the AC power supply is lost;
a first voltage detection means (80) that detects a value of a first voltage being
the output of the control power-source means;
a first determination means (83) that determines whether or not the first voltage
value is a first threshold value or smaller; and
a supply means (Se) that supplies the DC power from the rechargeable battery to the
control means when the first voltage value becomes the first threshold value or smaller;
characterized by
a discharge means (35) that discharges electric charges in the capacitor in response
to loss of the AC power supply;
a second voltage detection means (180) that detects a second voltage value being a
value of the voltage across the capacitor (26); and
a second determination means (183) that determines whether or not the second voltage
value is larger than a second threshold value,
wherein the supply means (Se) supplies the DC power from the rechargeable battery
to the control means also when the second voltage value is larger than the second
threshold value.
2. The elevator control system according to claim 1, wherein the control power-source
means includes, at least, a first and a second control power-source means whose outputs
are connected in parallel to each other, and wherein the first control power-source
means supplies a DC voltage to the control means, and the supply means supplies the
DC power from the second control power-source means to the control means when the
first voltage value becomes the first threshold value or smaller.
3. The elevator control system according to claim 2, wherein the output voltage of the
second control power-source means is lower than that of the first control power-source
means.
4. The elevator control system according to claim 3, wherein the first control power-source
means generates a first positive bias voltage for turning on the switching elements
and a first negative bias voltage for turning off the switching elements, and the
second control power-source means generates only a second negative bias voltage for
turning off the switching elements.
5. The elevator control system according to claim 4, wherein the switching elements constitute
an upper arm and a lower arm, and the switching elements of the lower arm are turned
off by the second negative bias voltage.
6. The elevator control system according to claim 4,
wherein the second control power-source means generates a single output of the second
negative bias voltage which is always connected to one of the first control power-source
means outputs supplied to the plurality of switching elements of the lower arm, and
wherein application means are provided that apply the single output of the second
negative bias voltage to the rest of the lower arm switching elements when the first
determination means determines that the first voltage value is the first threshold
value or smaller.
7. The elevator control system according to any one of claims 1 to 6, wherein the switching
elements are made up of a wide band gap semiconductor.
1. Aufzugsteuersystem, umfassend:
einen Wandler (24), der elektrischen Strom von einer Wechselstromquelle (20) in einen
Gleichstrom unter Verwendung von Halbleiterelementen umwandelt;
einen Kondensator (26), der den Gleichstrom glättet;
einen Inverter (30), der den Gleichstrom in einen beliebigen Wechselstrom unter Verwendung
von Schaltelementen (31) umwandelt und einen Motor (11), der eine Aufzugskabine (9)
bewegt, antreibt;
ein Steuermittel (60), das eine An-Aus-Steuerung der Schaltelemente durchführt;
ein Steuer-Stromquellen-Mittel (50), das einen Gleichstrom auf Basis der Wechselstromversorgung
erzeugt und das Steuermittel mit dem Gleichstrom versorgt;
eine wieder aufladbare Batterie (52), die das Steuer-Stromquellen-Mittel mit einem
Gleichstrom versorgt, wenn die Wechselstromversorgung verloren geht;
ein erstes Spannungserfassungsmittel (80), das einen Wert einer ersten Spannung erfasst,
die die Ausgabe des Steuer-Stromquellen-Mittels ist;
ein erstes Bestimmungsmittel (83), das bestimmt, ob oder ob nicht die erste Spannung
ein erster Schwellwert oder kleiner ist;
ein Versorgungsmittel (Se), das das Steuermittel mit dem Gleichstrom von der wieder
aufladbaren Batterie versorgt, wenn der erste Spannungswert der erste Schwellwert
oder kleiner wird;
gekennzeichnet durch
ein Entlademittel (35), das elektrische Ladungen in den Kondensator ansprechend auf
einen Verlust der Wechselstromversorgung entlädt;
ein zweites Spannungserfassungsmittel (180), das einen zweiten Spannungswert erfasst,
der ein Wert der Spannung über dem Kondensator (26) ist; und
ein zweites Bestimmungsmittel (183), das bestimmt ob oder ob nicht der zweite Spannungswert
größer als ein zweiter Schwellwert ist,
wobei das Versorgungsmittel (Se) das Steuermittel auch mit dem Gleichstrom von der
wieder aufladbaren Batterie versorgt, wenn der zweite Spannungswert größer als der
zweite Schwellwert ist.
2. Aufzugsteuersystem nach Anspruch 1, wobei das Steuer-Stromquellen-Mittel zumindest
ein erstes und ein zweites Steuer-Stromquellen-Mittel enthält, deren Ausgaben parallel
zueinander verbunden sind, und wobei das erste Steuer-Stromquellen-Mittel das Steuermittel
mit einer Gleichspannung versorgt, und das Versorgungsmittel das Steuermittel mit
dem Gleichstrom von dem zweiten Steuer-Stromquellen-Mittel versorgt, wenn der erste
Spannungswert der erste Schwellwert oder kleiner wird.
3. Aufzugsteuersystem nach Anspruch 2, wobei die Ausgangsspannung des zweiten Steuer-Stromquellen-Mittels
kleiner als diejenige des ersten Steuer-Stromquellen-Mittels ist.
4. Aufzugsteuersystem nach Anspruch 3, wobei das erste Steuer-Stromquellen-Mittel eine
erste positive Biasspannung zum Anschalten der Schaltelemente und eine erste negative
Biasspannung zum Ausschalten der Schaltelemente erzeugt und das zweite Steuer-Stromquellen-Mittel
nur eine zweite negative Biasspannung zum Ausschalten der Schaltelemente erzeugt.
5. Aufzugsteuersystem nach Anspruch 4, wobei die Schaltelemente einen oberen Arm und
einen unteren Armen bilden und die Schaltelemente des unteren Arms durch die zweite
negative Biasspannung ausgeschaltet werden
6. Aufzugsteuersystem nach Anspruch 4,
wobei das zweite Steuer-Stromquellen-Mittel eine einzelne Ausgabe der zweiten negativen
Biasspannung erzeugt, die immer mit einer der ersten Steuer-Stromquellen-Mittel-Ausgaben
verbunden ist, mit denen die die Vielzahl der Schaltelemente des oberen Arms versorgt
werden, und
wobei Anlegungsmittel bereitgestellt werden, die die einzelne Ausgabe der zweiten
negativen Biasspannung an dem Rest der unteren Arms-Schaltelemente anlegt, wenn das
erste Bestimmungsmittel bestimmt, dass die erste Spannung der erste Schwellwert oder
kleiner ist.
7. Aufzugsteuersystem nach einem der Ansprüche 1 bis 6, wobei die Schaltelemente aus
einem Breitbandlücken-Halbleiter gebildet werden.
1. Système de commande d'ascenseur comprenant :
un convertisseur (24) qui convertit une énergie électrique provenant d'une alimentation
en courant alternatif (20) en courant continu en utilisant des éléments semi-conducteurs;
un condensateur (26) qui lisse le courant continu ;
un inverseur (30) qui convertit le courant continu en un courant alternatif quelconque
en utilisant des éléments de commutation (31) et pilote un moteur (11) déplaçant une
cabine d'ascenseur (9) ;
un moyen de commande (60) qui réalise une commande activé/désactivé des éléments de
commutation ;
un moyen source d'alimentation de commande (50) qui produit un courant continu sur
la base de l'alimentation en courant alternatif et fournit le courant continu au moyen
de commande;
une batterie rechargeable (52) qui fournit un courant continu au moyen source d'alimentation
de commande lorsque l'alimentation en courant alternatif est perdue;
un premier moyen de détection de tension (80) qui détecte une valeur d'une première
tension comme étant la sortie du moyen source d'alimentation de commande ;
un premier moyen de détermination (83) qui détermine si la première valeur de tension
est égale, ou non, à une première valeur de seuil ou une valeur inférieure ; et
un moyen d'alimentation (Se) qui fournit le courant continu provenant de la batterie
rechargeable au moyen de commande lorsque la première valeur de tension devient la
première valeur de seuil ou une valeur inférieure ;
caractérisé par
un moyen de décharge (35) qui évacue des charges électriques dans le condensateur
en réponse à la perte de l'alimentation en courant alternatif;
un second moyen de détection de tension (180) qui détecte une seconde valeur de tension
comme étant une valeur de la tension présente aux bornes du condensateur (26) ; et
un second moyen de détermination (183) qui détermine si la seconde valeur de tension
est, ou non, plus grande qu'une seconde valeur de seuil,
dans lequel le moyen d'alimentation (Se) fournit le courant continu provenant de la
batterie rechargeable au moyen de commande également lorsque la seconde valeur de
tension est plus grande que la seconde valeur de seuil.
2. Système de commande d'ascenseur selon la revendication 1, dans lequel le moyen source
d'alimentation de commande comporte au moins un premier et un second moyen source
d'alimentation de commande dont les sorties sont connectées en parallèle l'une à l'autre,
et dans lequel le premier moyen source d'alimentation de commande fournit une tension
en courant continu au moyen de commande, et le moyen d'alimentation fournit le courant
continu provenant du second moyen source d'alimentation de commande au moyen de commande
lorsque la première valeur de tension devient la première valeur de seuil ou une valeur
inférieure.
3. Système de commande d'ascenseur selon la revendication 2, dans lequel la tension de
sortie du second moyen source d'alimentation de commande est inférieure à celle du
premier moyen source d'alimentation de commande.
4. Système de commande d'ascenseur selon la revendication 3, dans lequel le premier moyen
source d'alimentation de commande produit une première tension de polarisation positive
pour activer les éléments de commutation et une première tension de polarisation négative
pour désactiver les éléments de commutation, et le second moyen source d'alimentation
de commande produit seulement une seconde tension de polarisation négative pour désactiver
les éléments de commutation.
5. Système de commande d'ascenseur selon la revendication 4, dans lequel les éléments
de commutation constituent une branche supérieure et une branche inférieure, et les
éléments de commutation de la branche inférieure sont désactivés par la seconde tension
de polarisation négative.
6. Système de commande d'ascenseur selon la revendication 4,
dans lequel le second moyen source d'alimentation de commande produit une sortie unique
de la seconde tension de polarisation négative qui est toujours connectée à une des
sorties du premier moyen source d'alimentation de commande fournies à la pluralité
d'éléments de commutation de la branche inférieure, et
dans lequel des moyens d'application sont agencés pour appliquer la sortie unique
de la seconde tension de polarisation négative au reste des éléments de commutation
de branche inférieure lorsque le premier moyen de détermination détermine que la première
valeur de tension est la première valeur de seuil ou une valeur inférieure.
7. Système de commande d'ascenseur selon l'une des revendications 1 à 6, dans lequel
les éléments de commutation sont constitués d'un semi-conducteur à large bande interdite.