CN111981634A - Electronic expansion valve closing method, valve control circuit board, power-off self-closing electronic expansion valve, electronic expansion valve coil cap and air conditioner - Google Patents

Abstract

The invention provides a closing method of an electronic expansion valve, a valve control circuit board, a self-closing electronic expansion valve after power failure, a coil cap of the electronic expansion valve and an air conditioner. The electronic expansion valve body is used to be arranged on a refrigerant pipeline; The valve body and the valve control circuit board, the MCU controller is set on the valve control circuit board, and the MCU controller is connected to control the opening and closing state of the electronic expansion valve body, which realizes the independent control of the electronic expansion valve body; the MCU controller also passes the detection circuit and The energy storage circuit module realizes external voltage detection and energy storage, that is, detects the voltage status of the main board of the indoor unit (external main board) to determine whether the main board is powered off. After the main board is powered off, the energy storage circuit module supplies energy to control the electronic expansion. The valve body is closed. It realizes the closing of the electronic expansion valve body through a simple energy storage circuit, and solves the problem that the refrigerant pipeline cannot be closed after a power failure.

Description

Electronic expansion valve closing method, valve control circuit board, self-closing electronic expansion valve after power failure, Electronic expansion valve coil cap and air conditioner

technical field

The invention relates to the technical field of air conditioning equipment, in particular to a method for closing an electronic expansion valve, a valve control circuit board, a self-closing electronic expansion valve after power failure, an electronic expansion valve coil cap and an air conditioner.

Background technique

Multi-connection means that one outdoor unit can be connected to multiple indoor unit units. It has the advantages of simple installation, low equipment cost, and small footprint. Products such as multi-connection and multi-pipe units are more and more widely used.

The basic principle of central air-conditioning products is to achieve cooling and heating through the phase change of the refrigerant. The electronic expansion valve body controls the flow of refrigerant to control the temperature in the room through the change of its own opening, so it is one of the most important components of air conditioners. The realization of electronic expansion valve body control is based on the control chip on the main control board of the indoor unit.

The central air conditioner can connect one outdoor unit to multiple indoor unit units for different commercial users or households. At this time, there is a problem. When one or several users leave home for a long time or need to disconnect the power supply of the air conditioner after get off work, There is a serious hidden danger: when the indoor unit suddenly loses power, the blower motor will stop rotating immediately, the drainage pump will stop working immediately, the electronic expansion valve body is at the opening degree before the power failure, and the outdoor unit is also running normally. , the refrigerant will continue to flow through the indoor unit in the state before the power failure. At this time, due to the loss of effective energy exchange, the refrigerant cannot be evaporated or cooled effectively, which can easily lead to failure.

For example: if the entire air conditioner indoor unit is in cooling mode when the power is turned off, the refrigerant will flow back to the outdoor unit in liquid form. Since the compressor cannot compress the liquid refrigerant, it will cause the entire system to fail and shut down or directly cause damage to the compressor; indoor side There are also the following situations: the air contains moisture, and there is no fan to supply air. Due to the continuous flow of the refrigerant, the surface temperature of the indoor unit heat exchanger will become lower and lower, and the outer surface temperature of the indoor unit will also become lower and lower, resulting in continuous flow. Condensate flow, causing property damage and even safety hazards. In the heating mode, the high-temperature and high-pressure refrigerant just discharged from the compressor passes through the indoor unit. Also, because heat exchange cannot be achieved, the refrigerant directly flows back to the outdoor unit, which will also cause the entire system to fail or damage the compressor.

Therefore, there is an urgent need for an electronic expansion valve that can be closed immediately after a power failure.

SUMMARY OF THE INVENTION

The invention aims to provide a self-closing electronic expansion valve after power failure, so as to solve the problem that the refrigerant pipeline cannot be closed after power failure.

The specific plans are as follows:

A method for closing an electronic expansion valve: a valve control circuit board with an energy storage module is arranged between an air conditioner mainboard and an electronic expansion valve; when the valve control circuit board detects that the air conditioner mainboard is powered off, the electronic expansion valve is closed.

In the present invention, the specific method for the valve control circuit board to close the electronic expansion valve is:

First, the valve control circuit board increases the output voltage to the electronic expansion valve; then, the valve control circuit board outputs the electronic expansion valve closing signal, and directly drives the electronic expansion valve to close.

The further technical scheme of the present invention is as follows: after the main board of the air conditioner is powered off and the electronic expansion valve is closed, the valve control circuit board stops the control of the energy storage module and the control of the electronic expansion valve, and enters a low-power standby state; when the valve control circuit board receives the air conditioner The main board electronic expansion valve drives the signal to release the low-power standby state and charge the energy storage module.

A valve control circuit board for controlling an electronic expansion valve body of an air conditioner, comprising a controller, a power supply port and a valve body connection port:

The controller is electrically connected to the valve body connection port to connect the electronic expansion valve body through the valve body connection port;

The controller is also electrically connected with a detection circuit module and an energy storage circuit module: both the detection circuit module and the energy storage circuit module are electrically connected to the power supply port.

A further technical solution of the present invention is: further comprising a signal input port, the signal input port is electrically connected to the controller, so as to be communicatively connected to the valve body connection port through the controller.

A further technical solution of the present invention is as follows: the valve control circuit board is further provided with a main power supply circuit electrically connected to the power supply port, the energy storage circuit module includes a charging circuit electrically connected to the main power supply circuit, and the charging circuit is provided with a power supply circuit. an energy storage element electrically connected to the controller.

A further technical solution of the present invention is: further comprising a drive amplifying circuit module, the controller is electrically connected to the drive amplifying circuit module, so as to be electrically connected to the valve body connection port through the drive amplifying circuit module;

The output end of the energy storage element is also electrically connected to a booster circuit, the booster circuit is unidirectionally connected to the main power supply circuit, and is electrically connected to the drive amplifying circuit module through the main power supply circuit.

The further technical scheme of the present invention is: the controller is an MCU controller, the boost circuit is a DC-DC boost topology; the energy storage element is a super capacitor or a battery, and correspondingly, the charging circuit is a linear constant current circuit or a BUCK DC -DC circuit; the energy storage element is electrically connected to the MCU controller through a voltage stabilization module, and the voltage stabilization module is a DC-DC/LDO voltage stabilizer.

A further technical solution of the present invention is as follows: both the detection circuit module and the energy storage circuit module are electrically connected to the main power supply circuit, and the detection circuit module is located close to the power supply port; the main power supply circuit is also provided with a diode, and the diode It corresponds to the position between the detection circuit module and the energy storage circuit module on the main power supply road.

A further technical solution of the present invention is that the detection circuit module is a pull-up resistor voltage divider circuit, which is electrically connected to the ADC module integrated in the MCU controller.

The present invention also provides an electronic expansion valve that is powered off and self-closing, comprising an electronic expansion valve body and the above valve control circuit board; the electronic expansion valve body is electrically connected to the valve body connection port.

The present invention also provides an air conditioner, comprising a refrigerant pipeline and a main board, on which the main board is provided with an electronic expansion valve body control signal output port and a drive power output port; it is characterized in that it also includes the above-mentioned electronic expansion self-shutoff after power failure. The electronic expansion valve body is arranged on the refrigerant pipeline, the electronic expansion valve body control signal output port of the main board is electrically connected to the MCU controller, and the drive power output port on the main board is electrically connected to the power supply port.

The present invention also provides an electronic expansion valve coil cap, which includes an insulating support and an excitation coil wound on the insulating support; and also includes the above valve control circuit board, and the valve body connection port is electrically connected to the excitation coil.

Beneficial effects: the electronic expansion valve closing method, valve control circuit board, power-off self-closing electronic expansion valve, electronic expansion valve coil cap and air conditioner of the present invention, the electronic expansion valve body is used to set on the refrigerant pipeline; Electronic expansion valve body and valve control circuit board. The valve control circuit board is provided with an MCU controller, which is connected with the MCU controller and controls the opening and closing state of the electronic expansion valve body, realizing the independent control of the electronic expansion valve body; the MCU controller also controls the electronic expansion valve body through The detection circuit and the energy storage circuit module realize external voltage detection and energy storage, that is, detect the voltage status of the main board of the indoor unit (external main board) to determine whether the main board is powered off. After the main board is powered off, the MCU controller supplies power through the energy storage circuit module. It can work, and the output signal controls the valve body to close. It realizes the closing of the valve body through a simple energy storage circuit, and solves the problem that the refrigerant pipeline cannot be closed after power failure.

Description of drawings

FIG. 1 shows a schematic diagram of the circuit principle of an air conditioner with a power-off self-closing electronic expansion valve according to Embodiment 1 of the present invention;

Fig. 2 shows the circuit diagram of Fig. 1;

FIG. 3 shows a schematic diagram of the circuit principle of the coil cap of the electronic expansion valve according to the second embodiment of the present invention;

FIG. 4 shows a schematic diagram of the circuit principle of an air conditioner with an electronic expansion valve that is powered off and self-closing according to Embodiment 3 of the present invention.

Detailed ways

To further illustrate the various embodiments, the present invention is provided with the accompanying drawings. These drawings are a part of the disclosure of the present invention, which are mainly used to illustrate the embodiments, and can be used in conjunction with the relevant description of the specification to explain the operation principles of the embodiments. With reference to these contents, one of ordinary skill in the art will understand other possible embodiments and advantages of the present invention. Components in the figures are not drawn to scale, and similar component symbols are often used to represent similar components.

The present invention will now be further described with reference to the accompanying drawings and specific embodiments.

1 , this embodiment provides an air conditioner with a power-off self-closing electronic expansion valve, the air conditioner includes a refrigerant pipeline (not shown in the figure), an indoor unit main board 10, and an electronic expansion valve body 30 and valve control circuit board 20 ; the electronic expansion valve body 30 is arranged on the refrigerant pipeline, and the main board 10 is electrically connected to the valve control circuit board 20 .

The electronic expansion valve body 30 is used to be installed on the refrigerant pipeline of the indoor unit of the air conditioner, so as to control the flow of the refrigerant through the change of the opening degree of the electronic expansion valve body, so as to control the indoor temperature. The electronic expansion valve body 30 is electrically connected to the main board 10 of the indoor unit outside this embodiment through the valve control circuit board 20, and the main board 10 of the indoor unit is used to supply power to the valve control circuit board 20 and output the electronic expansion valve body control signal to control cooling capacity.

The valve control circuit board 20 is respectively provided with a MCU control circuit module, a detection circuit module and an energy storage circuit module.

The MCU control circuit module includes an MCU controller 1. The MCU controller 1 is electrically connected to a driving amplifying circuit module 2 through a main communication line, and the driving amplifying circuit module 2 is electrically connected to the electronic expansion valve body 30, and is then controlled by the MCU. The controller 1 controls the opening degree change of the electronic expansion valve body 30; in order to achieve the maximum compatibility of the air conditioner, the MCU controller 1 is also provided with a communication interface, so as to be electrically connected to the main board 10 of the indoor unit through the communication interface, receive and transmit The control signal of the main board 10 of the indoor unit realizes the independent control of the electronic expansion valve body 30 and maximizes the compatibility effect.

The MCU controller 1 is powered by an energy storage circuit module with DC power, and the energy storage circuit module includes a charging circuit 4 and an energy storage element 5 that are electrically connected in sequence, and the energy storage element 5 is electrically connected to the MCU controller 1 for power supply; The energy storage element 5 is also connected in parallel with a booster circuit 6 , which is used to provide a normal working voltage to the driving amplifier circuit module 2 to realize the driving of the electronic expansion valve body 30 .

The MCU controller 1 is electrically connected to the power output terminal of the indoor unit mainboard 10 through the detection circuit module 3 to detect the output voltage and indirectly measure the power-on or power-off state of the indoor unit mainboard 10 . Furthermore, when the main board 10 of the indoor unit is powered, the control signal of the main board 10 of the indoor unit is received, so that the main board 10 of the indoor unit controls the electronic expansion valve body 30; when the output voltage of the main board 10 of the indoor unit is reduced or zero, it is determined that the indoor unit The main board 10 is powered off, and the energy storage element 5 supplies power to the MCU controller 1 and the drive amplifier circuit module 2 to output a closing signal and drive the electronic expansion valve body 30 to close.

In conjunction with Fig. 2 again, the further technical scheme of the present invention is:

The valve control circuit board 20 is provided with a main power supply circuit 21 for connecting to an external main board. The detection circuit module 3 and the charging circuit 4 are both electrically connected to the main power supply circuit 21, and the detection circuit module 3 is arranged in the Close to the side of the connection end of the main board 10 of the indoor unit; the main power supply circuit 21 is also provided with a diode 22, and the diode 22 is arranged on the main power supply circuit 21 corresponding to the position between the detection circuit module 3 and the charging circuit 4 to Ensure that the internal circuit is isolated from the outside after power failure, and improve the utilization rate of electric energy.

The detection circuit module 3 is a pull-up resistor voltage divider circuit, which is electrically connected to the built-in ADC module of the MCU controller to detect the voltage value and determine the power-off condition of the indoor unit main board 10 .

The signal of the input voltage is transmitted to the ADC module inside the MCU controller by means of resistance division, so as to detect whether the input is powered off, and the filter capacitor can play a role in reducing interference. If the voltage signal is lower than a certain set value a for a certain period of time, it is judged that the system is powered off, and when the voltage signal is higher than a certain set value b greater than the set value a for a certain period of time, it is judged that the system is powered on.

The charging circuit 4 is electrically connected to the main power supply circuit. In this embodiment, the charging circuit is a linear constant current circuit, the energy storage element 5 is a super capacitor, and the energy storage element 5 is electrically connected through a voltage regulator 51 to the MCU controller 1 to supply power to the MCU controller. Preferably, the voltage regulator is a DC-DC/LDO voltage regulator; at the same time, since the level of the energy storage element will be lower than the level of the power supply line, in order to ensure the electronic For the normal operation of the expansion valve body, the level of the energy storage element needs to be raised to the original level of the power supply circuit through the booster circuit: the output end of the energy storage element 5 is also electrically connected to a booster circuit 6, and the booster circuit is DC. -DCboost topology, which is unidirectionally connected to the main power supply circuit 21 to be electrically connected to the drive amplifying circuit module 2 through the power supply main circuit 21. In this embodiment, the drive amplifying circuit module 2 is a drive amplifying circuit The integrated chip realizes the power supply to the MCU control module.

Of course, in other preferred solutions, the energy storage element can also be a battery, and correspondingly, the charging circuit is a BUCK DC-DC circuit; the drive amplifying circuit module can also be a separate device, and the separate device is electrically connected to form a drive amplifying circuit.

Whether the energy storage element 5 is charged needs to be determined according to its state. If it is a battery, when the system is powered on and the battery is lower than a certain voltage value, the charging part will work, and when the battery is fully charged, the charging part will stop working, which is mainly to ensure the life of the battery. If it is a super capacitor, the charging part can always work as long as the system is powered on. In addition, the state of the energy storage element can be sampled in the form of resistive voltage division, and the signal is converted and sent to the ADC inside the MCU for sampling. The MCU can control whether the charging circuit works through this state. Of course, the charging circuit can also inform the MCU of the state of the energy storage element through the I/O port.

MCU control circuit, in the power-on state of the system, the circuit receives the control signal sent by the main board, and obtains the control information of the main board in the form of a pull-up resistor and voltage divider. The MCU transmits this information to the drive amplifying circuit module, that is, the drive amplifying circuit for amplification, and then transmits it to the electronic expansion valve body to control it to open and close. When the system is powered off, the control information of the main board will be lost. At this time, the MCU will send a shutdown signal by itself. After driving the amplifying circuit through the driving amplifying circuit module, it will be sent to the electronic expansion valve body, and the valve body will be closed.

In the existing air-conditioning equipment control technology, since the electronic expansion valve body controls the refrigerant flow to control the temperature in the room, its control accuracy is the most important indicator that affects the air-conditioning performance. Therefore, in order to realize the precise control of the electronic expansion valve body, various manufacturers have made a lot of efforts to ensure that the control of the electronic expansion valve body is accurate and reasonable, and the control chip on the main control board of the indoor unit is directly controlled. The technical solution breaks through the existing technical ideas. The control of the electronic expansion valve body in the working state and the closing of the electronic expansion valve body after the power failure are completed by different components, so that the action of the electronic expansion valve body after the power failure is separated from the indoor unit. The main control board greatly reduces the control difficulty and technical cost.

In other specific implementations, the valve control circuit board can also be used as an adapter circuit board connecting the main board of the indoor unit and the electronic expansion valve, or the valve control circuit board and the electronic expansion valve body can be integrated into an independent functional element. The valve body connection port, power supply port and signal input port are set on the control circuit board to connect the electronic expansion valve, the power supply end and the signal end of the main board of the indoor unit. Each port here can be an independent socket structure or a circuit board. It can also be the pin of an integrated chip or an electronic component, etc., which can be connected in a variety of ways.

Embodiment 2

In the existing practical life, air-conditioning equipment has been widely used, and the existing air-conditioning equipment in use does not have the function of automatically closing the electronic expansion valve after power failure. In order to solve the problem that the refrigerant pipeline of the installed air conditioner cannot be closed after power failure, this embodiment provides an electronic expansion valve coil cap integrated with the valve control circuit board 20 in Embodiment 1, as shown in FIG. 3 .

The electronic expansion valve body in the prior art (ie the electronic expansion valve body 30 of the first embodiment) is mainly composed of two parts: a coil part and an execution part; and the coil part is used as a coil cap, which is detachably sleeved on the execution part to form an electronic expansion valve body.

The coil part includes an insulating support and an excitation coil 300 wound on the insulating support; the excitation coil 300 is wound on the insulating support by wires one by one, and the wires are insulated from each other. The executive part is mainly composed of stainless steel casing, magnet rotor, nut, screw shaft, needle valve, body and connecting pipe. Wherein, the magnet rotor rotates under the driving action of the excitation coil 300 to realize the adjustment of the opening degree. And in actual use, the execution part has been fixedly installed by the copper pipe and the throttling component, such as joints, copper pipes, etc. are generally welded to the stainless steel casing or link pipe group, and cannot be removed separately.

The valve control circuit board 20 of this embodiment is basically the same as the embodiment, and includes an MCU control circuit module, a detection circuit module and an energy storage circuit module.

The MCU control circuit module includes an MCU controller 1, the MCU controller 1 is electrically connected to a driving amplifying circuit module 2 through a communication main line, and the driving amplifying circuit module 2 is electrically connected to the excitation coil 300; the detection circuit module 3 is Pull-up resistor voltage divider circuit, the charging circuit 4 is electrically connected to the main power supply circuit, the charging circuit 4 is a linear constant current circuit, and the energy storage element 5 is a super capacitor.

In this embodiment, preferably, the coil part further includes a casing, the valve control circuit board 20 is arranged in the casing, and then the casing is sleeved on the insulating support and covers the excitation coil 300 . At this time, the interface on the valve control circuit board 20 is electrically connected to the excitation coil 300 .

The coil cap of the electronic expansion valve in this embodiment can directly replace the coil part of the electronic expansion valve body in the prior art, so as to solve the problem that the refrigerant pipeline cannot be closed after the power failure of the old model with minimum cost.

Example 3

4 , this embodiment provides an air conditioner with an electronic expansion valve that is powered off and self-closing, the principle of which is basically the same as that of Embodiment 1: the air conditioner includes a refrigerant pipeline (not shown in the figure) and an indoor The main board 10 includes an electronic expansion valve body 30 and a valve control circuit board 20; the electronic expansion valve body 30 is arranged on the refrigerant pipeline, and the main board 10 is electrically connected to the valve control circuit board.

Among them, the valve control circuit board includes a main power supply circuit 21, a detection circuit module 3 for power failure detection, a charging circuit 4, a boost circuit 6 and a drive amplifying circuit module 2; wherein, the charging circuit 4 is a linear constant current The circuit, which is electrically connected to the energy storage element 5 is a super capacitor, and the energy storage element 5 is electrically connected to the MCU controller 1 through a voltage regulator 51 .

The main difference between this embodiment and Embodiment 1 is:

In this embodiment, the air conditioner indoor unit further includes a system power supply circuit 8, which may be AC 15V, DC 12V or a specific voltage converted from a 220V AC input in the air conditioning system. This part of the circuit provides power supply and voltage detection source for the relevant modules of this embodiment, that is, it is electrically connected to the main power supply circuit 21 .

When the system is powered off, the system power supply circuit 8 cannot provide power supply. To close the expansion valve at this time, a supply voltage required by the expansion valve is required, but this voltage is usually higher than the battery voltage of the energy storage element 5 . The MCU controller 1 drives the booster circuit 6 to actively boost the battery voltage to the required voltage; at the same time, the voltage output by the booster circuit 6 is detected in real time by the output voltage detection circuit 7, and the result is fed back to the MCU controller 1 to ensure that the The voltage is normal, and then drive the electronic expansion valve to act.

In this embodiment, since the charging circuit 4 and the boosting circuit 6 do not work at the same time, they can be simplified into a composite circuit module, sharing devices such as MOSFETs, and controlled by the MCU controller 1; and in the specific implementation manner, the MCU controls The controller can also be a single-chip microcomputer, PLC or other programmable controllers.

This embodiment also provides a method for closing an electronic expansion valve.

A valve control circuit board with an energy storage module is arranged between the main board of the air conditioner and the electronic expansion valve; when the valve control circuit board detects that the main board of the air conditioner is powered off, the electronic expansion valve is closed.

Specifically, the specific method for the valve control circuit board to close the electronic expansion valve is: first, the valve control circuit board increases the output voltage to the electronic expansion valve; then, the valve control circuit board outputs the electronic expansion valve closing signal, and The direct drive electronic expansion valve closes.

And the main board of the air conditioner is powered off and the electronic expansion valve is closed, the valve control circuit board stops the control of the energy storage module and the control of the electronic expansion valve, and enters a low-power standby state; when the valve control circuit board receives the electronic expansion valve drive signal of the main board of the air conditioner, Release the low-power standby state and charge the energy storage module.

This control method avoids the occurrence of incorrect valve closing. The circuit will record whether the main board of the indoor unit of the air conditioner sends a signal of over-driving the valve body. When the air-conditioning system is powered off after working for a period of time, the controller in the circuit makes the booster circuit work. After the voltage is appropriate, it outputs a control signal to drive the valve body to close, and then the system sleeps with low power consumption. When the system is powered on, the controller makes the charging circuit work to charge the battery.

Preferably, after the circuit detects that the system is powered on, it starts to monitor whether a power failure occurs. If it does not meet a certain period of time, it is not considered to be a normal power failure phenomenon, and the instruction to close the valve body is not executed. After the system is powered off, delay the decision to close the valve for a period of time to ensure that the power supply is not unstable, or the valve is repeatedly closed. After the system is powered on, turn on the charging circuit after a delay of time to ensure that the power supply is not unstable, or the phenomenon of repeated charging occurs.

The electronic expansion valve closing method of the present invention can not only realize the protection scenario of the existing scheme, but also has various applicable situations, such as the power supply of the air conditioner is normal but the rear circuit is faulty, such as the circuit of the main control board of the air conditioner and the circuit of the electronic expansion valve, etc. , the electronic expansion valve closing method of the present invention can still perform the function of protection closing and shutting off, and the protection is more pertinent and the protection range is wider.

Compared with the external circuit power supply scheme for the main control board of the air conditioner, the external circuit consumes more power devices. When a power failure occurs, the valve closing action is performed. Due to the large amount of power, the battery size will also be large, the cost of the whole solution is high, and due to the characteristics of the battery, its effective life is short (about 3 years), which does not match the life of the air conditioner of about 15 years, and customers will again face If the water leakage risk of the valve cannot be closed, or the device is purchased again, the electronic expansion valve closing method of the present invention can solve this pain point, and the cost is also greatly reduced and the size is small.

The electronic expansion valve closing method protection circuit of the present invention is integrated with the electronic expansion valve, is applicable to all air conditioners, has wide applicability, and does not need to adjust the existing control program of the air conditioner; the products sold on the market can also be directly upgraded and replaced. Save a lot of software upgrade costs and expenses for manufacturers. There is no need for air conditioner installers to change the original circuit, which solves the problem that the external circuit is inconvenient to operate and needs to find additional space for fixing due to its large size, which increases the difficulty of construction and the risk of errors.

Although the present invention has been particularly shown and described in connection with preferred embodiments, it will be understood by those skilled in the art that changes in form and detail may be made to the present invention without departing from the spirit and scope of the invention as defined by the appended claims. Various changes are made within the protection scope of the present invention.

Claims (10)

1. An electronic expansion valve closing method is characterized in that: a valve control circuit board with an energy storage module is provided between the air conditioner mainboard and the electronic expansion valve; when the valve control circuit board detects that the air conditioner mainboard is powered off, the electronic Expansion valve. 2. The electronic expansion valve closing method according to claim 1, wherein the specific method for the valve control circuit board to close the electronic expansion valve is: First, the valve control circuit board increases the output voltage to the electronic expansion valve; then, the valve control circuit board outputs the electronic expansion valve closing signal, and directly drives the electronic expansion valve to close. 3. The method for closing an electronic expansion valve according to claim 1, wherein the main board of the air conditioner is powered off, and after the electronic expansion valve is closed, the valve control circuit board stops the control of the energy storage module and the control of the electronic expansion valve, and enters the low power consumption Standby state; when the valve control circuit board receives the drive signal of the electronic expansion valve of the main board of the air conditioner, the low-power standby state is released, and the energy storage module is charged. 4. A valve control circuit board for controlling an electronic expansion valve body of an air conditioner, characterized in that it comprises a controller, a power supply port and a valve body connection port: The controller is electrically connected to the valve body connection port to connect the electronic expansion valve body through the valve body connection port; The controller is also electrically connected with a detection circuit module and an energy storage circuit module: both the detection circuit module and the energy storage circuit module are electrically connected to the power supply port. 5. The valve control circuit board according to claim 4, wherein: It also includes a signal input port, the signal input port is electrically connected to the controller to communicate with the valve body connection port through the controller. 6. The valve control circuit board according to claim 4, wherein: The valve control circuit board is also provided with a main power supply circuit electrically connected to the power supply port, the energy storage circuit module includes a charging circuit electrically connected to the main power supply circuit, the charging circuit is provided with an energy storage element, the energy storage element electrically connected to the controller; further comprising a drive amplifying circuit module, the controller is electrically connected to the drive amplifying circuit module, so as to be electrically connected to the valve body connection port through the drive amplifying circuit module; The output end of the energy storage element is also electrically connected to a booster circuit, the booster circuit is unidirectionally connected to the main power supply circuit, and is electrically connected to the drive amplifying circuit module through the main power supply circuit. 7. The valve control circuit board according to claim 6, wherein: The boost circuit is a DC-DC boost topology, the controller is an MCU controller; the energy storage element is a super capacitor or a battery, correspondingly, the charging circuit is a linear constant current circuit or a BUCK DC-DC circuit; the energy storage element It is electrically connected to the MCU controller through a voltage stabilization module, and the voltage stabilization module is a DC-DC/LDO voltage regulator; The detection circuit module and the energy storage circuit module are both electrically connected to the main power supply circuit, and the detection circuit module is located close to the power supply port; the main power supply circuit is also provided with a diode, and the diode is arranged on the main power supply circuit and corresponds to the detection The position between the circuit module and the energy storage circuit module; the detection circuit module is a pull-up resistor voltage divider circuit, which is electrically connected to the ADC module integrated inside the controller. 8. A self-closing electronic expansion valve when power off, comprising an electronic expansion valve body, characterized in that, further comprising the valve control circuit board according to any one of claims 4-7; the electronic expansion valve body and the valve body The connection port is electrically connected. 9. An air conditioner, comprising a refrigerant pipeline, a main board provided with an electronic expansion valve body control signal output port and a drive power output port; it is characterized in that it also comprises the self-closing electronic expansion valve according to claim 8; The electronic expansion valve body is arranged on the refrigerant pipeline, the electronic expansion valve body control signal output port of the main board is electrically connected to the controller, and the drive power output port on the main board is electrically connected to the power supply port. 10. An electronic expansion valve coil cap, comprising an insulating support and an excitation coil wound on the insulating support; characterized in that: further comprising the valve control circuit board according to any one of claims 4-7, the valve body The connection port is electrically connected to the excitation coil.

Images