FIELD
[0001] The present disclosure relates to a heat pump system and a method for starting a
heat pump system.
BACKGROUND
[0002] With the development of heat pump technology, more and more heat pump products are
put into the market. The more functions the heat pump product has, the more complex
the heat pump product is, and the more heat exchangers are used in the heat pump product.
For example, a multi-connected air conditioner has a plurality of indoor heat exchangers,
and an air-source-heat recycling air-conditioning water heater not only has an air
heat exchanger but also has a hot water heat exchanger. When not all the heat exchangers
are used at one time, there will be refrigerant deposited in the unused heat exchanger,
thus causing a change to the amount of refrigerant utilized in the systemic circulation.
If this change is not controlled, it will seriously influence a safe operation of
the heat pump system. Therefore, there is a need to improve a usage rate of the refrigerant
and to reduce an influence of the deposited refrigerant on the heat pump system. The
existing solutions comprise increasing the refrigerant charge and circulating the
refrigerant in all the heat exchangers periodically.
[0003] However, the existing solutions have the following defects:
- 1. Although increasing the refrigerant charge can solve the problem of a shortage
of operating refrigerant in some cases, the over-charged refrigerant will bring a
potential danger to the heat pump system. For example, when there is no deposited
refrigerant in some circulation, increasing the refrigerant charge will result in
that there is too much refrigerant utilized in the systemic circulation, which is
easy to produce a liquid strike, thus damaging a compressor of the heat pump system.
Moreover, in order to avoid the above problem, it is necessary to increase some fluid
reservoirs, which in turn increases the complexity and cost of the heat pump system.
- 2. Although circulating the refrigerant in all the heat exchangers periodically can
solve the problem of oil return and redistribution of the refrigerant, all the heat
exchangers should be started (including the unused heat exchangers) during the circulation,
which will waste energy and cause inconveniences. Further, this method is only useful
for the air conditioner that realizes heating and refrigeration separately, but useless
for the multipurpose heat pump system (the refrigerant can't pass all the heat exchangers
during one circulation).
SUMMARY
[0004] The aim of the present disclosure is to solve at least one of the problems in the
related art.
[0005] According to embodiments of a first aspect of the present disclosure, a heat pump
system is provided. The heat pump system comprises: a compressor and a four-way valve;
an outdoor heat exchanger, connected with the compressor via the four-way valve; at
least one indoor heat exchanger, connected with the compressor via the four-way valve;
an outdoor control valve and at least one indoor control valve, in which the outdoor
heat exchanger is connected in series with each of the at least one indoor heat exchanger
via the outdoor control valve and via each of the at least one indoor control valve;
and a controller, connected with the four-way valve, the outdoor control valve, the
at least one indoor control valve and the compressor respectively, and configured
to control the compressor, the four-way valve, the outdoor control valve and the at
least one indoor control valve to open or close so as to control a circulation loop
of the heat-pump system to enter the start mode or the operation mode, wherein the
circulation loop is formed by the compressor, the four-way valve, the outdoor heat
exchanger, the at least one indoor heat exchanger, the outdoor control valve and the
at least one indoor control valve.
[0006] In some embodiments, the at least one indoor heat exchanger comprises a first indoor
heat exchanger and a second indoor heat exchanger; the at least one indoor control
valve comprises a first indoor control valve connected in series with the first indoor
heat exchanger and a second indoor valve connected in series with the second indoor
heat exchanger; the four-way valve comprises an discharge end, a condenser end, an
evaporator end and a suction end, an discharge port and a suction port of the compressor
are connected with the discharge end and the suction end of the four-way valve respectively;
two ends of the outdoor heat exchanger are connected with the condenser end of the
four-way valve and a first end of the outdoor control valve respectively, a second
end of the outdoor control valve is connected with the first indoor control vale and
the second indoor control valve respectively; the evaporator end of the four-way valve
is connected with the first indoor heat exchanger and the second indoor heat exchanger
respectively.
[0007] In some embodiments, the heat pump system further comprises a pressure sensor. The
pressure sensor is disposed on a pipeline connecting the suction end of the four-way
valve with the discharge port of the compressor, electrically connected with the controller
and configured to detect a pressure at the suction port of the compressor.
[0008] In some embodiments, when the controller controls the four-way valve to power down,
the discharge end is communicated with the condenser end, and the evaporator end is
communicated with the suction end; when the controller controls the four-way valve
to power on, the discharge end is communicated with the evaporator end, and the condenser
end is communicated with the suction end.
[0009] In some embodiments, when the heat pump system enters the start mode, the controller
adjusts the four-way valve to control the outdoor heat exchanger to enter a heat dissipation
state and to control the outdoor control valve to enter a closed state.
[0010] In some embodiments, the controller adjusts the four-way valve and the at least one
indoor control valve to control the heat pump system to enter the operation mode and
opens the outdoor control valve to adjust the operation mode.
[0011] In some embodiments, the operation mode is a full load refrigerating mode, a partial
load refrigerating mode, a full load heating mode or a partial load heating mode.
[0012] In some embodiments, when the heat pump system is operating in the full load refrigerating
mode, the discharge end is communicated with the condenser end, the evaporator end
is communicated with the suction end, the outdoor control valve, the first indoor
control valve and the second indoor control valve are open, the refrigerant passes
the outdoor heat exchanger, the outdoor heat exchanger is used as a condenser and
is in the heat dissipation state, and the outdoor control valve is used as an outlet
control valve for the outdoor heat exchanger.
[0013] In some embodiments, when the heat pump system is operating in the partial load refrigerating
mode, the discharge end is communicated with the condenser end, the evaporator end
is communicated with the suction end, the outdoor control valve and one of the first
indoor control valve and the second indoor control valve are open, the refrigerant
passes the outdoor heat exchanger, the outdoor heat exchanger is used as a condenser
and is in the heat dissipation state, and the outdoor control valve is used as an
outlet control valve for the outdoor heat exchanger.
[0014] In some embodiments, when the heat pump system is operating in the full load heating
mode, the discharge end is communicated with the evaporator end, the condenser end
is communicated with the suction end, the outdoor control valve, the first indoor
control valve and the second indoor control valve are open, the refrigerant passes
the outdoor heat exchanger, the outdoor heat exchanger is used as an evaporator and
is in a heat absorption state, and the outdoor control valve is used as an outlet
control valve for the outdoor heat exchanger.
[0015] In some embodiments, when the heat pump system is operating in the partial load heating
mode, the discharge end is communicated with the evaporator end, the condenser end
is communicated with the suction end, the outdoor control valve and one of the first
indoor control valve and the second indoor control valve are open, the refrigerant
passes the outdoor heat exchanger, the outdoor heat exchanger is used as an evaporator
and is in a heat absorption state, and the outdoor control valve is used as an outlet
control valve for the outdoor heat exchanger.
[0016] According to embodiments of a second aspect of the present disclosure, a method for
starting a heat pump system is provided. The method comprises: receiving a start instruction;
controlling the heat pump system to enter a start mode according to the start instruction;
recycling refrigerant in the heat pump system under the start mode; determining whether
the start mode is completed; and if yes, controlling the heat pump system to enter
an operation state.
[0017] In some embodiments, the heat pump system comprises a compressor and a four-way valve,
an outdoor heat exchanger connected with the compressor via the four-way valve, at
least one indoor heat exchanger connected with the compressor via the four-way valve,
and an outdoor control valve and at least one indoor control valve, the outdoor heat
exchanger is connected in series with each of the at least one indoor heat exchanger
via the outdoor control valve and via each of the at least one indoor control valve.
[0018] In some embodiments, controlling the heat pump system to enter a start mode comprises:
adjusting the four-way valve to control the outdoor heat exchanger to enter the heat
dissipation state and to control the outdoor control valve to enter the closed state.
[0019] In some embodiments, controlling the heat pump system to enter the operation mode
comprises: adjusting the four-way valve and the at least one indoor control valve
to control the heat pump system to enter the operation mode; and opening the outdoor
control valve to adjust the operation mode.
[0020] In some embodiments, the start mode is determined to be completed when any of the
following conditions is satisfied: a suction pressure of the compressor is lower than
a first preset pressure; a suction pressure of the compressor is lower than a second
preset pressure for a first preset time; a suction pressure of the compressor is lower
than a switch threshold of a suction pressure switch of the compressor for a second
preset time; and a recycle time of the refrigerant reaches a third preset time.
[0021] According to the heat pump system or the method for starting the heat pump system
of the present disclosure, by recycling refrigerant in the heat pump system into the
heat exchanger to be used for circulation, a reasonable distribution of the refrigerant
is realized, without increasing the refrigerant charge. Moreover, there is no need
to start all the heat exchangers, thus saving energy and reducing the influence of
the distribution of the refrigerant on the operation of the heat pump system. In addition,
the technical solutions of the present disclosure have a wide range of application
and can be widely applied to a variety of equipments which need the distribution of
the refrigerant.
[0022] These and other aspects and advantages of the invention will be present in the following
description, and part of them will become apparent or be understood through the embodiment
of the present disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] These and other aspects and advantages of the invention will become apparent and
more readily appreciated from the following descriptions taken in conjunction with
the drawings in which:
Fig. 1 is a schematic view of a heat pump system according to an embodiment of the
present disclosure;
Fig. 2 is a block diagram of a controller according to an embodiment of the present
disclosure;
Figs. 3-6 are schematic views showing flow paths of refrigerant in the heat pump system
of Fig. lunder different operation modes;
Fig. 7 is a flow chart of a method for starting a heat pump system according to an
embodiment of the present disclosure;
Fig. 8 is a flow chart of a method for controlling the heat pump system to enter a
partial load heating mode according to an embodiment of the present disclosure; and
Fig. 9 is a flow chart of a method for controlling the heat pump system to enter a
partial load refrigerating mode according to an embodiment of the present disclosure.
DETAILED DESCRIPTION
[0024] Reference will be made in detail to embodiments of the present disclosure. The embodiments
described herein with reference to drawings are explanatory, illustrative, and used
to generally understand the present disclosure. The embodiments shall not be construed
to limit the present disclosure. The same or similar elements and the elements having
same or similar functions are denoted by like reference numerals throughout the descriptions.
[0025] In the specification, unless specified or limited otherwise, relative terms such
as "central", "longitudinal", "lateral", "front", "rear", "right", "left", "inner",
"outer", "lower", "upper", "horizontal", "vertical", "above", "below", "up", "top",
"bottom", "peripheral" as well as derivative thereof (e.g., "horizontally", "downwardly",
"upwardly", etc.) should be construed to refer to the orientation as then described
or as shown in the drawings under discussion. These relative terms are for convenience
of description and do not require that the present disclosure be constructed or operated
in a particular orientation. In addition, terms such as "first" and "second" are used
herein for purposes of description and are not intended to indicate or imply relative
importance or significance.
[0026] In the following, a heat pump system and a method for starting the heat pump system
according to embodiments of the present disclosure will be described in detail with
reference to drawings.
[0027] Fig. 1 is a schematic view of a heat pump system according to an embodiment of the
present disclosure. As shown in Fig. 1, the heat pump system 20 comprises a compressor
1, a four-way valve 2, an outdoor heat exchanger 3, a first indoor heat exchanger
4, a second indoor heat exchanger 5, an outdoor control valve 6, a first indoor control
valve 7, a second indoor control valve 8 and a controller 10.
[0028] The outdoor heat exchanger 3, the first indoor heat exchanger 4 and the second indoor
heat exchanger 5 are connected with the compressor 1 respectively via the four-way
valve 2. The outdoor heat exchanger 3 is connected in series with the first indoor
heat exchanger 4 via the outdoor control valve 6 and the first indoor control valve
7. The outdoor heat exchanger 3 is connected in series with the second indoor heat
exchanger 5 via the outdoor control valve 6 and the second indoor control valve 8.
The compressor 1, the four-way valve 2, the outdoor heat exchanger 3, the first indoor
heat exchanger 4, the second indoor heat exchange 5, the outdoor control valve 6 and
the first indoor control valve 7 and the second indoor control valve 8 connected with
each other form a circulation loop.
[0029] The controller 10 is electrically connected with the four-way valve 2, the outdoor
control valve 6, the first indoor control valve 7, the second indoor control valve
8 and the compressor 1, and is configured to control the compressor 1, the four-way
valve 2, the outdoor control valve 6, the first indoor control valve 7 and the second
indoor control valve 8 to open or close so as to control the heat pump system 20 to
enter a start mode or an operation mode.
[0030] It should be understood that, the heat pump system 20 shown in Fig. 1 is only illustrative,
and is not used to limit the scope of the present disclosure. The heat pump system
according to the present disclosure may comprise any number of indoor heat exchangers
and a same number of indoor control valves. In other words, the heat pump system may
comprise at least one indoor heat exchanger and at least one indoor control valves.
The at least one indoor heat exchanger is connected with the compressor 1 via the
four-way valve 2. The outdoor heat exchanger 3 is connected in series with each of
the at least one indoor heat exchanger via the outdoor control valve 6 and via each
of the at least one indoor control valve. The circulation loop is formed by the compressor
1, the four-way valve 2, the outdoor heat exchanger 3, the at least one indoor heat
exchanger, the outdoor control valve 6 and the at least one indoor control valve.
[0031] Specifically, as shown in Fig. 1, the four-way valve 2 comprises a discharge end
(d), a condenser end (c), an evaporator end (e) and a suction end (s). A discharge
port and a suction port of the compressor 1 are connected with the discharge end (d)
and the suction end (s) of the four-way valve 2 respectively. Two ends of the outdoor
heat exchanger 3 are connected with the condenser end (c) of the four-way valve 2
and a first end of the outdoor control valve 6 respectively. A second end of the outdoor
control valve 6 is connected with the first indoor control vale 7 and the second indoor
control valve 8 respectively. The evaporator end (e) of the four-way valve 2 is connected
with the first indoor heat exchanger 4 and the second indoor heat exchanger 5 respectively.
[0032] In one embodiment, when the controller 10 controls the four-way valve 2 to power
down, the discharge end (d) is communicated with the condenser end (c), and the evaporator
end (e) is communicated with the suction end (s). When the controller 10 controls
the four-way valve 2 to power on, the discharge end (d) is communicated with the evaporator
end (e), and the condenser end (c) is communicated with the suction end (s).
[0033] Fig. 2 is a block diagram of the controller 10 according to an embodiment of the
present disclosure. As shown in Fig. 2, the controller 10 comprises a receiving module
110, a first executing module 120, a determining module 130 and a second executing
module 140. The receiving module 110 is configured to receive a start instruction.
The first executing module 120 is electrically connected with the receiving device
110 and is configured to control the heat pump system to enter a start mode according
to the start instruction, and to control the refrigerant in the circulation loop to
be recycled under the start mode. The determining module 130 is configured to determine
whether the start mode is completed. The second executing module 140 is electrically
connected with the determining module 130, and is configured to control the heat pump
system 20 to enter the operation mode when the start mode is completed.
[0034] In order to facilitate determining whether the refrigerant in the circulation loop
is recycled completely, a pressure sensor 9 may be disposed on a pipeline connecting
the suction end (s) of the four-way valve 2 with the discharge port of the compressor
1. The pressure sensor 9 is electrically connected with the controller 10 and is configured
to detect a pressure at the suction port of the compressor 1. In one embodiment, when
the pressure sensor 9 detects that the pressure at the suction port of the compressor
1 is 0 MPa or when the operating time of the compressor 1 during the start mode exceeds
30 seconds, it is determined that the start mode is completed.
[0035] Specifically, when the heat pump system 20 enters the start mode, the first executing
module 120 adjusts the four-way valve 2 to control the outdoor heat exchanger 3 to
enter a heat dissipation state and to control the outdoor control valve 6 to enter
a closed state. When the heat pump system 20 completes the start mode, the second
executing module 140 adjusts the four-way valve 2, the first indoor control valve
7 and the second indoor control valve 8 to control the heat pump system 20 to enter
the operation mode and opens the outdoor control valve 6 to adjust the operation mode.
[0036] The first executing module 120 and the second executing module 130 may be independently
disposed, or may be integrated into a single chip.
[0037] The operation mode of the heat pump system 20 is a full load refrigerating mode,
a partial load refrigerating mode, a full load heating mode or a partial load heating
mode.
[0038] Figs. 3-6 are schematic views showing flow paths of refrigerant in the heat pump
system 20 under different operation modes. As shown in Fig. 3, when the heat pump
system 20 is operating in the full load refrigerating mode, the four-way valve 2 is
powered down, i.e., the discharge end (d) is communicated with the condenser end (c),
the evaporator end (e) is communicated with the suction end (s). The outdoor control
valve 6, the first indoor control valve 7 and the second indoor control valve 8 are
open. The flow path of the refrigerant is as follows: the discharge port of the compressor
1→ the discharge end (d)→ the condenser end (c)→ the outdoor heat exchanger 3→ the
outdoor control valve 6→ the first indoor control valve 7 and the second indoor control
valve 8→ the first indoor heat exchanger 4 and the second indoor heat exchanger 5→
the evaporator end (e) → the suction end (s)→ the suction port of the compressor 1.
In this mode, the refrigerant passes the outdoor heat exchanger 3, the outdoor heat
exchanger 3 is used as a condenser and is in the heat dissipation state, and the outdoor
control valve 6 is used as an outlet control valve for the outdoor heat exchanger
3.
[0039] As shown in Fig. 4, when the heat pump system 20 is operating in the partial load
refrigerating mode, the four-way valve 2 is powered down, i.e., the discharge end
(d) is communicated with the condenser end (c), the evaporator end (e) is communicated
with the suction end (s). The outdoor control valve 6 and one of the first indoor
control valve 7 and the second indoor control valve 8 are open. The flow path of the
refrigerant is as follows: the discharge port of the compressor 1→ the discharge end
(d)→ the condenser end (c)→ the outdoor heat exchanger 3→ the outdoor control valve
6→ the first indoor control valve 7 or the second indoor control valve 8→ the firs
indoor heat exchanger 4 or the second indoor heat exchanger 5→ the evaporator end
(e)→ the suction end (s)→ the suction port of the compressor 1. In this mode, the
refrigerant passes the outdoor heat exchanger 3, the outdoor heat exchanger 3 is used
as a condenser and is in the heat dissipation state, and the outdoor control valve
6 is used as an outlet control valve for the outdoor heat exchanger 3.
[0040] As shown in Fig. 5, when the heat pump system 20 is operating in the full load heating
mode, the four-way valve 2 is powered on, i.e., the discharge end (d) is communicated
with the evaporator end (e), the condenser end (c) is communicated with the suction
end (s). The outdoor control valve 6, the first indoor control valve 7 and the second
indoor control valve (8) are open. The flow path of the refrigerant is as follows:
the discharge port of the compressor 1→ the discharge end (d)→ the evaporator end
(e)→ the first indoor heat exchanger 4 and the second indoor heat exchanger 5→ the
first indoor control valve 7 and the second indoor control valve 8→ the outdoor control
valve 6→ the outdoor heat exchanger 3→ the condenser end (c)→ the suction end (s)→
the suction port of the compressor 1. In this mode, all the refrigerant passes the
outdoor heat exchanger 3, the outdoor heat exchanger 3 is used as an evaporator and
is in a heat absorption state, and the outdoor control valve 6 is used as an outlet
control valve for the outdoor heat exchanger 3.
[0041] As shown in Fig. 6, when the heat pump system 20 is operating in the full load heating
mode, the four-way valve 2 is powered on, i.e., the discharge end (d) is communicated
with the evaporator end (e), the condenser end (c) is communicated with the suction
end (s). The outdoor control valve 6 and one of the first indoor control valve 7 and
the second indoor control valve 8 are open. The flow path of the refrigerant is as
follows: the discharge port of the compressor 1→ the discharge end (d)→ the evaporator
end (e)→ the first indoor heat exchanger 4 or the second indoor heat exchanger 5→
the first indoor control valve 7 or the second indoor control valve 8→ the outdoor
control valve 6→ the outdoor heat exchanger 3→ the condenser end (c)→ the suction
end (s) → the suction port of the compressor 1. In this mode, the refrigerant passes
the outdoor heat exchanger 3, the outdoor heat exchanger 3 is used as an evaporator
and is in a heat absorption state, and the outdoor control valve 6 is used as an outlet
control valve for the outdoor heat exchanger 3.
[0042] According to the heat pump system of the present disclosure, by recycling the refrigerant
in the circulation loop into the heat exchanger to be used for circulation, a reasonable
distribution of the refrigerant in the heat pump system is realized, without increasing
the refrigerant charge. Moreover, there is no need to start all the heat exchangers,
thus saving energy and reducing the influence of the distribution of the refrigerant
on the operation of the heat pump system. In addition, the controller has a wide range
of application and can be widely applied to a variety of equipments which need the
distribution of the refrigerant.
[0043] Fig. 7 is a flow chart of a method for starting the above heat pump system. As shown
in Fig. 7, the method comprises the following steps.
[0044] At step S1, a start instruction is received.
[0045] At step S2, the heat pump system is controlled to enter a start mode according to
the start instruction.
[0046] At step S3, the refrigerant in the heat pump system is recycled. Specifically, when
the heat pump system enters the start mode, the controller adjusts the four-way valve
to control the outdoor heat exchanger to enter the heat dissipation state and to control
the outdoor control valve to enter the closed state, so as to recycle the refrigerant
in the heat pump system under the start mode.
[0047] At step S4, it is determined whether the start mode is completed. Specifically, the
start mode is determined to be completed when any of the following conditions is satisfied:
(1) a suction pressure of the compressor is lower than a first preset pressure; (2)
a suction pressure of the compressor is lower than a second preset pressure for a
first preset time; (3) a suction pressure of the compressor is lower than a switch
threshold of a suction pressure switch of the compressor for a second preset time;
(4) a recycle time of the refrigerant reaches a third preset time. In one embodiment,
the first preset pressure is -0.1-8 MPa, the second preset pressure is -0.1-8 MPa,
the first preset time is 0-180 seconds, the switch threshold of the suction pressure
switch is -0.1-8 MPa; the second preset time is 0-180 seconds, and the third preset
time is 1-180 seconds.
[0048] At step S5, the heat pump system is controlled to enter an operation mode when the
start mode is completed. Specifically, the controller adjusts the four-way valve and
the at least one indoor control valve to control the heat pump system to enter the
operation mode, and then opens the outdoor control valve to adjust the operation mode.
In one embodiment, the operation mode comprises a full load refrigerating mode, a
partial load refrigerating mode, a full load heating mode or a partial load heating
mode.
[0049] According to the method for starting the heat pump system of the present disclosure,
by recycling the refrigerant in the heat pump system into the heat exchanger to be
used for circulation, a reasonable distribution of the refrigerant in the heat pump
system is realized, without increasing the refrigerant charge. Moreover, with the
method for starting the heat pump system according to embodiments of the present disclosure,
there is no need to start all the heat exchangers, thus saving energy and reducing
the influence of the distribution of the refrigerant on the operation of the heat
pump system. In addition, the method according to the present disclosure has a wide
range of application and can be widely applied to a variety of equipments which need
the distribution of the refrigerant.
[0050] Fig. 8 is a flow chart of a method for controlling the heat pump system to enter
a partial load heating mode according to an embodiment of the present disclosure.
As shown in Fig. 8, the method comprises the following steps.
[0051] At step S11, a start instruction is received. The start instruction indicates that
the heat pump system is desired to enter the partial load heating mode.
[0052] At step S21, the heat pump system is controlled to enter a start mode according to
the start instruction.
[0053] At step S31, the refrigerant in the heat pump system is recycled under the start
mode. Specifically, the controller adjusts the four-way valve to power down to make
the outdoor heat exchanger enter a heat dissipation state and closes the outdoor control
valve, such that the refrigerant is recycled.
[0054] At step S41, it is determined whether the start mode is completed. Specifically,
when a suction pressure of the compressor is lower than a first preset pressure and/or
when the recycle time of the refrigerant reaches a preset time, it is determined that
the start mode is completed.
[0055] At step S51, the heat pump system is controlled to enter an operation state when
the start mode is completed. Specifically, when the start mode is completed, the controller
adjusts the four-way valve to power on and controls the outdoor control valve 6 to
enter the operation state.
[0056] Fig. 9 is a flow chart of a method for controlling the heat pump system to enter
a partial load refrigerating mode according to an embodiment of the present disclosure.
As shown in Fig. 9, the method comprises the following steps.
[0057] At step S12, a start instruction is received. The start instruction indicates that
the heat pump system is desired to enter the partial load refrigerating mode.
[0058] At step S22, the heat pump system is controlled to enter a start mode according to
the start instruction.
[0059] At step S32, the refrigerant in the heat pump system is recycled under the start
mode. Specifically, the controller adjusts the four-way valve to power down to make
the outdoor heat exchanger enter the heat dissipation state and closes the outdoor
control valve, such that the refrigerant is recycled.
[0060] At step S41, it is determined whether the start mode is completed. Specifically,
when a suction pressure of the compressor is lower than a first preset pressure and/or
when the recycle time of the refrigerant reaches a preset time, it is determined that
the start mode is completed.
[0061] At step S51, the heat pump system is controlled to enter an operation state when
the start mode is completed. Specifically, when the start mode is completed, the controller
adjusts the four-way valve to power on and controls the outdoor control valve to enter
the operation state.
[0062] According to the method for starting the heat pump system of the present disclosure,
by recycling the refrigerant in the heat pump system into the heat exchanger to be
used for circulation, a reasonable distribution of the refrigerant in the heat pump
system is realized without increasing the refrigerant charge, and the refrigerant
is prevented from depositing into the second indoor heat exchanger during downtime,
thus saving energy and reducing the influence of the distribution of the refrigerant
on the operation of the heat pump system. In addition, the method according to the
present disclosure has a wide range of application and can be widely applied to a
variety of equipments which need the distribution of the refrigerant.
[0063] According to the method for starting the heat pump system of the present disclosure,
the refrigerant is distributed before the heat pump system enters the operation mode
(i.e., the refrigerant is distributed during the start control for the heat pump system),
and when the start control for the heat pump system is completed, there is no need
to distribute the refrigerant during the operation mode of the heat pump system, which
does not break the balance of the operation and improves the conveniences. Specifically,
with the method of the present disclosure, at every time when the heat pump system
starts, almost all of the refrigerant in the heat pump system is recycled into one
heat exchanger, and is utilized by each circulation, which can realize a reasonable
distribution of the refrigerant without additionally increasing the refrigerant charge,
thus avoiding a negative impact on the heat pump system caused by too much refrigerant.
In addition, with the method according to the present disclosure, it is not necessary
for all the heat exchangers to participate in a same circulation procedure, which
greatly simplifies the system design and reduces the energy cost of the system. Thus,
the method can be widely applied to a variety of products needing the distribution
of the refrigerant, such as a multi-connected air-conditioner unit, a unit type heat-recycle
air-conditioning water heater unit, a multi-connected heat-recycle air-conditioning
water heater unit, a three-tube multi-connected unit, and a multi-functional multi-heat-resource
heat pump unit. Certainly, the method will not occupy too much operation time of the
heat pump system, and has an advantage of high distribution efficiency.
[0064] In the description of the present disclosure, it should be noticed that unless specified
or limited otherwise, the terms "mounted," "connected," "supported," and "coupled"
and variations thereof are used broadly and encompass both direct and indirect mountings,
connections, supports, and couplings. For the general technician in the field, the
above terms can be understood according to the detail embodiment of the present disclosure.
[0065] Reference throughout this specification to "an embodiment," "some embodiments," "one
embodiment", "another example," "an example," "a specific example," or "some examples,"
means that a particular feature, structure, material, or characteristic described
in connection with the embodiment or example is included in at least one embodiment
or example of the present disclosure. Thus, the appearances of the phrases throughout
this specification are not necessarily referring to the same embodiment or example
of the present disclosure. Furthermore, the particular features, structures, materials,
or characteristics may be combined in any suitable manner in one or more embodiments
or examples.
[0066] Although explanatory embodiments have been shown and described, it would be appreciated
by those skilled in the art that the above embodiments cannot be construed to limit
the present disclosure, and changes, alternatives, and modifications can be made in
the embodiments without departing from spirit, principles and scope of the present
disclosure.
1. A heat pump system, comprising:
a compressor and a four-way valve;
an outdoor heat exchanger, connected with the compressor via the four-way valve;
at least one indoor heat exchanger, connected with the compressor via the four-way
valve;
and
an outdoor control valve and at least one indoor control valve, wherein the outdoor
heat exchanger is connected in series with each of the at least one indoor heat exchanger
via the outdoor control valve and via each of the at least one indoor control valve,
and
a controller, connected with the four-way valve, the outdoor control valve, the at
least one indoor control valve and the compressor respectively, and configured to
control the compressor, the four-way valve, the outdoor control valve and the at least
one indoor control valve to open or close so as to control a circulation loop of the
heat-pump system to enter the start mode or the operation mode, wherein the circulation
loop is formed by the compressor, the four-way valve, the outdoor heat exchanger,
the at least one indoor heat exchanger, the outdoor control valve and the at least
one indoor control valve.
2. The heat pump system according to claim 1, wherein the at least one indoor heat exchanger
comprises a first indoor heat exchanger and a second indoor heat exchanger; the at
least one indoor control valve comprises a first indoor control valve connected in
series with the first indoor heat exchanger and a second indoor valve connected in
series with the second indoor heat exchanger; the four-way valve comprises an discharge
end, a condenser end, an evaporator end and a suction end, an discharge port and a
suction port of the compressor are connected with the discharge end and the suction
end of the four-way valve respectively; two ends of the outdoor heat exchanger are
connected with the condenser end of the four-way valve and a first end of the outdoor
control valve respectively, a second end of the outdoor control valve is connected
with the first indoor control vale and the second indoor control valve respectively;
the evaporator end of the four-way valve is connected with the first indoor heat exchanger
and the second indoor heat exchanger respectively.
3. The heat pump system according to claim 2, further comprising:
a pressure sensor, disposed on a pipeline connecting the suction end of the four-way
valve with the discharge port of the compressor, electrically connected with the controller
and configured to detect a pressure at the suction port of the compressor.
4. The heat pump system according to claim 2, wherein when the controller controls the
four-way valve to power down, the discharge end is communicated with the condenser
end, and the evaporator end is communicated with the suction end; when the controller
controls the four-way valve to power on, the discharge end is communicated with the
evaporator end, and the condenser end is communicated with the suction end.
5. The heat pump system according to any of claims 1-4, wherein when the heat pump system
enters the start mode, the controller adjusts the four-way valve to control the outdoor
heat exchanger to enter a heat dissipation state and to control the outdoor control
valve to enter a closed state.
6. The heat pump system according to claim 5, wherein the controller adjusts the four-way
valve and the at least one indoor control valve to control the heat pump system to
enter the operation mode and opens the outdoor control valve to adjust the operation
mode.
7. The heat-pump system according to any of claims 1-6, wherein the operation mode is
a full load refrigerating mode, a partial load refrigerating mode, a full load heating
mode or a partial load heating mode.
8. The heat pump system according to claim 7, wherein when the heat pump system is operating
in the full load refrigerating mode, the discharge end is communicated with the condenser
end, the evaporator end is communicated with the suction end, the outdoor control
valve, the first indoor control valve and the second indoor control valve are open,
all the refrigerant passes the outdoor heat exchanger, the outdoor heat exchanger
is used as a condenser and is in the heat dissipation state, and the outdoor control
valve is used as an outlet control valve for the outdoor heat exchanger.
9. The heat pump system according to claim 7, wherein when the heat pump system is operating
in the partial load refrigerating mode, the discharge end is communicated with the
condenser end, the evaporator end is communicated with the suction end, the outdoor
control valve and one of the first indoor control valve and the second indoor control
valve are open, the refrigerant passes the outdoor heat exchanger, the outdoor heat
exchanger is used as a condenser and is in the heat dissipation state, and the outdoor
control valve is used as an outlet control valve for the outdoor heat exchanger.
10. The heat pump system according to claim 7, wherein when the heat pump system is operating
in the full load heating mode, the discharge end is communicated with the evaporator
end, the condenser end is communicated with the suction end, the outdoor control valve,
the first indoor control valve and the second indoor control valve are open, the refrigerant
passes the outdoor heat exchanger, the outdoor heat exchanger is used as an evaporator
and is in a heat absorption state, and the outdoor control valve is used as an outlet
control valve for the outdoor heat exchanger.
11. The heat pump system according to claim 7, wherein when the heat pump system is operating
in the partial load heating mode, the discharge end is communicated with the evaporator
end, the condenser end is communicated with the suction end, the outdoor control valve
and one of the first indoor control valve and the second indoor control valve are
open, determine the refrigerant passes the outdoor heat exchanger, the outdoor heat
exchanger is used as an evaporator and is in a heat absorption state, and the outdoor
control valve is used as an outlet control valve for the outdoor heat exchanger.
12. A method for starting a heat pump system, comprising:
receiving a start instruction;
controlling the heat pump system to enter a start mode according to the start instruction;
recycling refrigerant in the heat pump system under the start mode;
determining whether the start mode is completed; and
if yes, controlling the heat pump system to enter an operation mode.
13. The method according to claim 12, wherein the heat pump system comprises a compressor
and a four-way valve, an outdoor heat exchanger connected with the compressor via
the four-way valve, at least one indoor heat exchanger connected with the compressor
via the four-way valve, and an outdoor control valve and at least one indoor control
valve, the outdoor heat exchanger is connected in series with each of the at least
one indoor heat exchanger via the outdoor control valve and via each of the at least
one indoor control valve, and the method further comprises:
adjusting the four-way valve to control the outdoor heat exchanger to enter the heat
dissipation state and to control the outdoor control valve to enter the closed state,
so as to recycle the refrigerant in the heat pump system under the start mode, and
14. The method according to claim 12 or 13, wherein controlling the heat pump system to
enter the operation mode comprises:
adjusting the four-way valve and the at least one indoor control valve to control
the heat pump system to enter the operation mode; and
opening the outdoor control valve to adjust the operation mode.
15. The method according to any of claims 12-14, wherein the start mode is determined
to be completed when any of the following conditions is satisfied:
a suction pressure of the compressor is lower than a first preset pressure;
a suction pressure of the compressor is lower than a second preset pressure for a
first preset time;
a suction pressure of the compressor is lower than a switch threshold of a suction
pressure switch of the compressor for a second preset time; and
a recycle time of the refrigerant reaches a third preset time.