A driving circuit of a motor, a driving current adjusting method and an air conditioning system

Abstract

The application discloses a driving circuit of a motor, a driving current adjusting method and an air conditioning system. The driving circuit comprises a driving chip, a microcontroller and phases of the motor, wherein the driving chip is connected with phase detection terminals of the motor, the microcontroller and the phases of the motor, is used for detecting phases of driving currents of the motor and outputting detection signals to the microcontroller; an adjusting circuit is connected with the microcontroller at an input end and is connected with a reference voltage input end of the driving chip at an output end; and the microcontroller is used for adjusting a duty cycle of a pulse width modulation wave output by the microcontroller according to the phases of the driving currents of the motor, and then adjusting a reference voltage input by the driving chip, so that the driving chip adjusts the driving currents of the motor based on the reference voltage. Through the application, the problem that driving failure is caused by the fact that the size of a driving signal does not match a motor model, and the refrigerant cannot be recovered, can be avoided, and the operation stability and safety of the air conditioning system are improved.

Description

Technical Field

[0001] This invention relates to the field of electronic circuit technology, and more specifically, to a motor drive circuit, a drive current regulation method, and an air conditioning system. Background Technology

[0002] Refrigerant, as the refrigerant in an air conditioning system, is crucial to the system's cooling performance. If refrigerant leaks and its concentration decreases for any reason, it will not only affect the cooling effect but also pose a safety hazard to users, as some refrigerants are toxic. Therefore, it is necessary to take measures to prevent refrigerant leaks from causing these problems. In practical applications, if a refrigerant leak occurs, the refrigerant is generally recovered to the outdoor unit by controlling the opening of the inlet valve and the closing of the outlet valve. The opening and closing of these valves are driven by a motor. Different motor models require different drive signal strengths. If the drive signal strength is incompatible with the motor model, the drive will fail, resulting in the inability to recover the refrigerant.

[0003] There is currently no effective solution to the problem that the magnitude of the drive signal does not match the motor model in the existing technology, causing drive failure and resulting in the inability to recover refrigerant. Summary of the Invention

[0004] This invention provides a motor drive circuit, a drive current adjustment method, and an air conditioning system to solve the problem in the prior art where the magnitude of the drive signal does not match the motor model, causing drive failure and resulting in the inability to recover refrigerant.

[0005] To solve the above-mentioned technical problems, the present invention provides a motor drive circuit, wherein the motor is used to control the opening and closing of a valve in an air conditioning system, the valve being disposed on the outlet or inlet pipe of the outdoor unit of the air conditioning system, and the drive circuit includes:

[0006] The driver chip is connected to the phase detection terminal of the motor, each phase of the motor, and the microcontroller; it is used to detect the phase of the drive current of the motor and output the detection signal to the microcontroller.

[0007] The adjustment circuit has its input terminal connected to the microcontroller and its output terminal connected to the reference voltage input terminal of the driver chip.

[0008] The microcontroller is used to adjust the duty cycle of the pulse width modulation wave output by the microcontroller according to the phase of the motor drive current, thereby adjusting the reference voltage input to the drive chip, so that the drive chip adjusts the drive current of the motor based on the reference voltage.

[0009] Furthermore, the microcontroller includes:

[0010] The judgment unit is used to determine whether the phase of the driving current is consistent with the preset phase;

[0011] The first execution unit is used to control the duty cycle of the output pulse width modulation wave to remain unchanged when the phase of the driving current is consistent with the preset phase.

[0012] The second execution unit is used to adjust the duty cycle of the pulse width modulation wave output by the microcontroller when the phase of the drive current is inconsistent with the preset phase, so as to adjust the drive current of the motor.

[0013] Furthermore, the adjustment circuit includes:

[0014] An optocoupler, wherein the emitter of the internal phototransistor is connected to the reference voltage input terminal of the driver chip through a voltage divider circuit, and the collector of the internal phototransistor is connected to a first voltage source; the anode of the internal light-emitting diode is connected to a second voltage source, and the cathode is connected to the collector of the switching transistor.

[0015] The switching transistor has its base connected to the microcontroller and its emitter grounded.

[0016] Furthermore, the voltage divider circuit includes:

[0017] A first resistor and a second resistor are connected in series. The first resistor is connected to the emitter of the phototransistor inside the optocoupler, and the second resistor is grounded. The line between the first resistor and the second resistor is connected to the reference voltage input terminal of the driver chip.

[0018] The first capacitor is connected in parallel across the two ends of the second resistor.

[0019] Furthermore, the driving circuit also includes:

[0020] A refrigerant detection device, the output of which is connected to the microcontroller, is used to transmit the refrigerant leakage signal to the microcontroller;

[0021] The microcontroller is also used to output the pulse width modulation wave after detecting the refrigerant leakage signal.

[0022] Furthermore, the microcontroller also includes:

[0023] A low-power control terminal, connected to the driver chip, is used to control the driver chip to standby at the lowest power consumption when the refrigerant detection device does not output a refrigerant leakage signal.

[0024] The present invention also provides an air conditioning system, including a valve, the valve being disposed on the outlet pipe or inlet pipe of the outdoor unit of the air conditioning system, and the air conditioning system further including the aforementioned drive circuit.

[0025] The present invention also provides a driving current adjustment method applied to the above-mentioned driving circuit, the method comprising:

[0026] Obtain the phase of the motor's drive current;

[0027] The duty cycle of the pulse width modulation wave output by the microcontroller in the drive circuit is adjusted according to the phase of the drive current of the motor, thereby adjusting the reference voltage input to the drive chip, so that the drive chip adjusts the drive current of the motor based on the reference voltage.

[0028] The driving chip is connected to the phase detection terminal of the motor, each phase of the motor, and the microcontroller. The driving circuit also includes an adjustment circuit, whose input terminal is connected to the microcontroller and whose output terminal is connected to the reference voltage input terminal of the driving chip.

[0029] Furthermore, the drive current of the motor is adjusted according to the duty cycle of the pulse width modulation wave output by the phase adjustment microcontroller of the motor's drive current, including:

[0030] Determine whether the phase of the driving current is consistent with the preset phase;

[0031] If so, the duty cycle of the pulse width modulation wave output by the microcontroller remains unchanged;

[0032] If not, adjust the duty cycle of the pulse width modulation wave output by the microcontroller to regulate the drive current of the motor.

[0033] Furthermore, adjusting the duty cycle of the pulse width modulation wave output by the microcontroller includes:

[0034] Determine the initial value of the motor's drive current and the current adjustment step size;

[0035] The duty cycle adjustment amount of the pulse width modulation wave is determined according to the current adjustment step size; wherein, the current adjustment step size and the duty cycle adjustment amount satisfy a preset correspondence.

[0036] The duty cycle of the pulse width modulation wave is increased or decreased according to the duty cycle adjustment amount until the phase of the driving current is consistent with the preset phase.

[0037] Furthermore, after controlling the duty cycle of the pulse width modulation wave to increase or decrease according to the duty cycle adjustment amount, the method further includes:

[0038] Determine if the current drive current value has reached the limit.

[0039] If so, the duty cycle of the pulse width modulation wave is adjusted according to a trend opposite to the current trend, based on the duty cycle corresponding to the initial value of the driving current.

[0040] Furthermore, after the phase of the driving current is consistent with the preset phase, the method further includes:

[0041] Determine if a refrigerant leak signal has been detected;

[0042] If so, the microcontroller is controlled to output a pulse width modulation wave that satisfies the current duty cycle in order to control the operation of the driver chip;

[0043] If not, the microcontroller is controlled to stop outputting pulse width modulation waves, and the driver chip is controlled to standby at the lowest power consumption.

[0044] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the program, when executed by a processor, implements the above-described drive current regulation method.

[0045] By applying the technical solution of this invention, the phase of the drive current is detected by the drive chip, and the duty cycle of the pulse width modulation wave output by the microcontroller is adjusted according to the phase of the drive current of the motor. This, in turn, adjusts the reference voltage input to the drive chip, and ultimately regulates the drive current of the motor. This enables the adjustment of the drive current to match the motor model when the drive current does not match the motor model, thus avoiding the problem of drive failure caused by the mismatch between the drive signal magnitude and the motor model, which leads to the inability to recover refrigerant. This improves the operational stability and safety of the air conditioning system. Attached Figure Description

[0046] Figure 1 A schematic diagram of refrigerant recovery in an existing air conditioning system;

[0047] Figure 2 This is a structural diagram of a motor drive circuit according to an embodiment of the present invention;

[0048] Figure 3 This is a structural diagram of a motor drive circuit according to another embodiment of the present invention;

[0049] Figure 4 A flowchart of a drive current adjustment method according to an embodiment of the present invention;

[0050] Figure 5 This is a flowchart of a drive current regulation method according to another embodiment of the present invention. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0052] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms, and “multiple” generally includes at least two unless the context clearly indicates otherwise.

[0053] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0054] Depending on the context, the words “if” or “suppose” as used here can be interpreted as “when” or “in response to determination” or “in response to detection.” Similarly, depending on the context, the phrases “if determination” or “if detection (of the stated condition or event)” can be interpreted as “when determination” or “in response to determination” or “when detection (of the stated condition or event)” or “in response to detection (of the stated condition or event).”

[0055] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device that includes said element.

[0056] The optional embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Example 1

[0057] Refrigerant, as the refrigerant in an air conditioning system, is crucial to the system's cooling performance. If refrigerant leaks and its concentration decreases for any reason, it will not only affect the cooling effect of the air conditioning system, but also pose a safety hazard to users, as some refrigerants are toxic. Therefore, it is necessary to take measures to prevent refrigerant leaks from causing these problems. Figure 1 A schematic diagram of refrigerant recovery in an existing air conditioning system, such as... Figure 1 As shown, in practical applications, if a refrigerant leak occurs, the refrigerant is generally recovered to the outdoor unit by controlling the opening of the inlet valve and the closing of the outlet valve. The opening and closing of these valves are driven by a motor. Different motor models require different drive signal strengths. If the drive signal strength is incompatible with the motor model, it will cause drive failure, resulting in the inability to recover the refrigerant.

[0058] To address the aforementioned problems, this embodiment provides a motor drive circuit. The motor controls the opening and closing of a valve in an air conditioning system. The valve is located on the outlet or inlet pipe of the outdoor unit of the air conditioning system. In this embodiment, the motor is a stepper motor. Figure 2 This is a structural diagram of the motor drive circuit according to an embodiment of the present invention, such as... Figure 2 As shown, the driving circuit includes:

[0059] The driver chip 1 is connected to the phase detection terminal of the motor, each phase of the motor, and the microcontroller, respectively, and is used to detect the phase of the drive current of the motor and output the detection signal to the microcontroller. The driver chip also includes at least two control terminals, one end of each control terminal is connected to the microcontroller, and the other end is connected to one phase of the motor.

[0060] The adjustment circuit 2 has its input connected to the microcontroller and its output connected to the reference voltage input of the driver chip. The microcontroller 3 adjusts the duty cycle of the pulse width modulation wave output by the microcontroller according to the phase of the motor's drive current, thereby adjusting the reference voltage input to the driver chip, so that the driver chip adjusts the motor's drive current based on the reference voltage. The driver chip has a single-phase current regulation module inside, which obtains the current of each phase of the motor based on the aforementioned reference voltage according to preset logic operations, and then controls the motor's drive current.

[0061] In practical implementation, the corresponding preset phase can be calculated based on the parameters of different motor models. Once the valve parameters are determined, the preset phase is fixed. If the magnitude of the motor's drive current matches the motor model, then the phase of the drive current is consistent with the preset phase. If the magnitude of the motor's drive current does not match the motor model, then the phase of the drive current is inconsistent with the preset phase. Therefore, it is necessary to adjust the magnitude of the drive current. In this embodiment, consistent phase means that the phases are the same, or the phase difference is within the preset range.

[0062] In this embodiment, the motor drive circuit detects the phase of the drive current through the drive chip 1. The microcontroller 3 adjusts the duty cycle of the pulse width modulation wave output by the microcontroller according to the phase of the motor drive current, thereby adjusting the reference voltage input to the drive chip. This ultimately achieves the adjustment of the motor drive current. When the drive current does not match the motor model, the drive current is adjusted to match the motor model. This avoids the problem of drive failure caused by the mismatch between the drive signal magnitude and the motor model, which leads to the inability to recover refrigerant. This improves the stability and safety of the air conditioning system. Example 2

[0063] This embodiment provides another motor drive circuit. Figure 3 This is a structural diagram of a motor drive circuit according to another embodiment of the present invention, as shown below. Figure 3 As shown, in order to adjust the drive current to match the motor model when the drive current does not match the motor model, the microcontroller integrates a microcontroller unit (MCU), which includes: a judgment unit for judging whether the phase of the drive current is consistent with a preset phase; a first execution unit for maintaining the duty cycle of the output pulse width modulation wave unchanged when the phase of the drive current is consistent with the preset phase; and a second execution unit for adjusting the duty cycle of the output pulse width modulation wave to regulate the drive current of the motor when the phase of the drive current is inconsistent with the preset phase.

[0064] Specifically, the second execution unit is used to: determine the initial value of the motor's drive current and the current adjustment step size; determine the duty cycle adjustment amount of the pulse width modulation wave according to the current adjustment step size; wherein, the current adjustment step size and the duty cycle adjustment amount satisfy a preset correspondence; the initial value of the drive current here is the default value of the drive current after the system is powered on, without any adjustment steps, and this value is fixed. The duty cycle of the pulse width modulation wave is controlled to increase or decrease according to the determined duty cycle adjustment amount until the phase of the drive current is consistent with the preset phase. To prevent the drive current from exceeding the upper and lower limits of the motor's drive current, after controlling the increase or decrease of the duty cycle of the pulse width modulation wave according to the duty cycle adjustment amount, it is also necessary to determine whether the current drive current value has reached the limit value, which includes an upper limit value and a lower limit value. When controlling the increase of the duty cycle of the pulse width modulation wave, it is determined whether the drive current value has reached the upper limit value; when controlling the decrease of the duty cycle of the pulse width modulation wave, it is determined whether the drive current value has reached the lower limit value. If so, the duty cycle of the pulse width modulation wave is adjusted according to the opposite trend of the current trend, based on the duty cycle corresponding to the initial value of the drive current. For example, if the current control of the pulse width modulation wave duty cycle is increasing, then when the drive current reaches the upper limit of the motor's drive current, the control of the pulse width modulation wave duty cycle is decreased based on the duty cycle corresponding to the initial value of the drive current. If the current control of the pulse width modulation wave duty cycle is decreasing, then when the drive current reaches the lower limit of the motor's drive current, the control of the pulse width modulation wave duty cycle is increased based on the duty cycle corresponding to the initial value of the drive current. If, during the process of increasing the duty cycle of the pulse width modulation (PWM) wave, the upper limit of the drive current value is reached, and then the control of decreasing the duty cycle of the PWM wave begins, only to reach the lower limit of the drive current value during the decreasing process; or, during the process of decreasing the duty cycle of the PWM wave, the lower limit of the drive current value is reached, and then the control of increasing the duty cycle of the PWM wave begins, only to reach the upper limit of the drive current value during the increasing process, in either of these two cases, the phase of the drive current is not adjusted to match the preset phase. However, if the adjustment continues, the drive current value will exceed the current range of the motor. In this case, it is considered that the drive current cannot match the motor model, and the adjustment of the drive current is stopped.

[0065] like Figure 3 As shown, the above-mentioned adjustment circuit includes: an optocoupler U2, whose internal phototransistor emitter is connected to the reference voltage input terminal of the driver chip through a voltage divider circuit, and whose collector is connected to the first voltage source DVDD; the internal light-emitting diode anode is connected to the second voltage source +VCC, and the cathode is connected to the collector of the switching transistor through a third resistor R3; and the switching transistor Q1, whose base is connected to the microcontroller 3 through a fourth resistor R4, and whose emitter is grounded.

[0066] The voltage divider circuit includes: a first resistor R1 and a second resistor R2 connected in series, the first resistor R1 being connected to the emitter of the phototransistor inside the optocoupler, the second resistor R2 being grounded, and the line between the first resistor R1 and the second resistor R2 being connected to the reference voltage input terminal of the driver chip 1; and a first capacitor C1 connected in parallel across the two ends of the second resistor R2.

[0067] To detect refrigerant leaks, such as Figure 3 As shown, the above-mentioned drive circuit also includes: a refrigerant detection device 4, whose output terminal is connected to a microcontroller 3, used to transmit a refrigerant leak signal to the microcontroller 3 when a refrigerant leak occurs; after detecting the refrigerant leak signal, the microcontroller 3 starts to output a pulse width modulation wave, controls the drive chip to work, and then drives the motor to run, controls the valve of the outdoor unit inlet pipe to open and the valve of the outlet pipe to close, so as to recover the refrigerant to the outdoor unit.

[0068] To reduce the power consumption of the entire system, such as Figure 3 As shown, the microcontroller also includes a low-power control terminal connected to the driver chip 1, used to control the driver chip to standby at the lowest power consumption when the refrigerant detection device 4 does not output a refrigerant leakage signal.

[0069] As mentioned above Figure 3As shown, CN1 is the electric valve interface, consisting of H-bridge circuit A terminal (first phase of the motor), H-bridge circuit B terminal (second phase of the motor), and a phase detection terminal. In this embodiment, the electric valve consists of a low-power bipolar two-phase motor and a valve body. The rotation of the motor causes the valve body to rotate. The valve body is located inside the pipe. In case of refrigerant leakage, the refrigerant is recovered into the outdoor unit by closing the outlet pipe and opening the inlet pipe. The motor drive chip 1 has an external circuit consisting of resistors and capacitors. The second capacitor C2 is the bootstrap capacitor for the charge pump circuit, and the third capacitor C3 is the charge pump energy storage capacitor, providing the high-side N-channel gate drive voltage for the H-bridge. NSLEEP, APH, and BPH are the low-power control terminal, H-bridge circuit A control terminal, and H-bridge circuit B control terminal of the chip, respectively. The drive chip is also connected to a 3.3V voltage source via a fifth resistor R5. This voltage source is used to enable the H-bridge circuits A and B of the drive chip. When this terminal is high, the drive chip is enabled. The chip has an internal attenuation control module with attenuation mode switching and turn-off time setting functions. When the current flowing through the H-bridge reaches the current threshold of the driver chip, current attenuation is activated to reduce the current, which is then completely reduced to zero after the set turn-off time. A reference voltage is input at the reference voltage input terminal. The single-phase current regulation module adjusts the current threshold flowing through H-bridge circuits A and B according to the input reference voltage, thereby changing the drive current to match valves requiring different drive currents. NFAULT is the phase detection signal input terminal, which can also serve as a low-voltage and over-temperature protection signal output terminal. This terminal has an open-drain output. The sixth resistor R6 is the pull-up resistor for this terminal. When the chip detects a phase abnormality, overcurrent, or overtemperature, it outputs a low level to the microcontroller 3, indicating a drive abnormality. The aforementioned drive circuit also includes a sixth capacitor C6, one end of which is grounded, and the other end is connected to the chip's internal power supply. A first voltage source DVDD is drawn between the sixth capacitor C6 and the internal power supply.

[0070] The fourth capacitor C4 is a high-frequency filter capacitor for the power supply, and the fifth capacitor C5 is a power storage capacitor to prevent voltage drops caused by insufficient power supply due to motor startup or other reasons. The high and low levels of the control pins of H-bridge circuit A and H-bridge circuit B determine the on-state of the switching transistors in H-bridge circuit A and H-bridge circuit B, thereby realizing the forward and reverse rotation of the motor.

[0071] Different motor models require different drive currents. To ensure compatibility with various motor models, the reference voltage of each phase input needs to be adjusted, thereby regulating the drive current. The microcontroller unit (MCU) outputs a PWM signal from the PWM_VREF terminal to drive the LED of optocoupler U2. The fourth resistor R4 is the base current limiting resistor for switch Q1, and the third resistor R3 is the collector current limiting resistor for switch Q1. The LED intensity of optocoupler U2 is determined by the duty cycle of PWM_VREF. The first resistor R1 and the second resistor R2 form a series voltage divider with the phototransistor inside optocoupler U2. The voltage between the first resistor R1 and the second resistor R2 is the reference voltage value. The first capacitor C1 is a filter capacitor for the reference voltage, used to stabilize the reference voltage. Therefore, the MCU can adjust the reference voltage value according to requirements by adjusting the duty cycle, thereby adjusting the current of each phase of the motor and ultimately regulating the drive current to match different motor models.

[0072] The analog electrical signal detected by the refrigerant leak detection device is transmitted to the analog-to-digital converter (ADC) of the microcontroller. After conversion by the ADC, when the refrigerant leak concentration reaches the set threshold, the drive chip is activated to drive the motor to run and recover the refrigerant into the outdoor unit, thereby avoiding safety accidents caused by refrigerant leaks. Example 3

[0073] This embodiment provides an air conditioning system, including a valve installed on the outlet or inlet pipe of the outdoor unit of the air conditioning system. The opening and closing of the valve is controlled by a motor. The air conditioning system of this embodiment also includes a drive circuit for the motor, which is used to adjust the drive current to match the motor model when the drive current does not match the motor model. This avoids the problem of drive failure caused by the mismatch between the drive signal and the motor model, resulting in the inability to recover refrigerant, and improves the operational stability and safety of the air conditioning system. Example 4

[0074] This embodiment provides a drive current regulation method, applied to the motor drive circuit in the above embodiment. Figure 4 The flowchart is as follows: A method for adjusting the drive current according to an embodiment of the present invention. Figure 4 As shown, the method includes:

[0075] S101, obtain the phase of the motor drive current.

[0076] S102, adjust the duty cycle of the pulse width modulation wave output by the microcontroller in the drive circuit according to the phase of the motor drive current, thereby adjusting the reference voltage input to the drive chip, so that the drive chip adjusts the motor drive current based on the reference voltage.

[0077] The drive chip is connected to the phase detection terminal of the motor, each phase of the motor, and the microcontroller. The drive circuit also includes an adjustment circuit, whose input is connected to the microcontroller and whose output is connected to the reference voltage input terminal of the drive chip. The drive chip has a single-phase current adjustment module that performs calculations according to preset logic, obtains the current of each phase of the motor based on the aforementioned reference voltage, and then controls the drive current of the motor.

[0078] In practical implementation, the corresponding preset phase can be calculated based on the parameters of different motor models. Once the valve parameters are determined, the preset phase is fixed. If the magnitude of the motor's drive current matches the motor model, then the phase of the drive current is consistent with the preset phase. If the magnitude of the motor's drive current does not match the motor model, then the phase of the drive current is inconsistent with the preset phase. Therefore, it is necessary to adjust the magnitude of the drive current. In this embodiment, consistent phase means that the phases are the same, or the phase difference is within the preset range.

[0079] The drive current adjustment method in this embodiment adjusts the duty cycle of the pulse width modulation wave output by the microcontroller based on the phase of the drive current of the motor, thereby adjusting the drive current of the motor. This achieves the goal of adjusting the drive current to match the motor model when the drive current does not match the motor model. It avoids the problem of drive failure caused by the mismatch between the drive signal magnitude and the motor model, which leads to the inability to recover refrigerant, and improves the operational stability and safety of the air conditioning system. Example 5

[0080] This embodiment provides another method for adjusting the drive current. To adjust the drive current to match the motor model when the drive current does not match the motor model, the duty cycle of the pulse width modulation wave output by the microcontroller is adjusted according to the phase of the motor's drive current. This includes: determining whether the phase of the drive current is consistent with a preset phase; if the phase of the drive current is consistent with the preset phase, the duty cycle of the output pulse width modulation wave remains unchanged; if the phase of the drive current is inconsistent with the preset phase, the duty cycle of the output pulse width modulation wave is adjusted to regulate the drive current of the motor.

[0081] Specifically, adjusting the duty cycle of the pulse width modulation (PWM) wave output by the microcontroller to regulate the drive current of the motor includes: determining the initial value of the motor's drive current and the current adjustment step size; determining the duty cycle adjustment amount of the PWM wave based on the current adjustment step size; wherein the current adjustment step size and the duty cycle adjustment amount satisfy a preset correspondence; the initial value of the drive current here is the default value of the drive current after the system is powered on, without any adjustment steps, and this value remains unchanged. The duty cycle of the PWM wave is controlled to increase or decrease according to the determined duty cycle adjustment amount until the phase of the drive current matches the preset phase. To prevent the drive current from exceeding the upper and lower limits of the motor's drive current, after controlling the increase or decrease of the duty cycle of the pulse width modulation wave according to the duty cycle adjustment amount, it is also necessary to determine whether the current drive current value has reached the limit value, which includes an upper limit value and a lower limit value. When controlling the increase of the duty cycle of the pulse width modulation wave, it is determined whether the drive current value has reached the upper limit value; when controlling the decrease of the duty cycle of the pulse width modulation wave, it is determined whether the drive current value has reached the lower limit value. If so, the duty cycle of the pulse width modulation wave is adjusted according to the opposite trend of the current trend, based on the duty cycle corresponding to the initial value of the drive current. For example, if the current control of the pulse width modulation wave duty cycle is increasing, then when the drive current reaches the upper limit of the motor's drive current, the control of the pulse width modulation wave duty cycle is decreased based on the duty cycle corresponding to the initial value of the drive current. If the current control of the pulse width modulation wave duty cycle is decreasing, then when the drive current reaches the lower limit of the motor's drive current, the control of the pulse width modulation wave duty cycle is increased based on the duty cycle corresponding to the initial value of the drive current. If, during the process of increasing the duty cycle of the pulse width modulation (PWM) wave, the upper limit of the drive current value is reached, and then the control of decreasing the duty cycle of the PWM wave begins, only to reach the lower limit of the drive current value during the decreasing process; or, during the process of decreasing the duty cycle of the PWM wave, the lower limit of the drive current value is reached, and then the control of increasing the duty cycle of the PWM wave begins, only to reach the upper limit of the drive current value during the increasing process, in either of these two cases, the phase of the drive current is not adjusted to match the preset phase. However, if the adjustment continues, the drive current value will exceed the current range of the motor. In this case, it is considered that the drive current cannot match the motor model, and the adjustment of the drive current is stopped.

[0082] In order to achieve timely recovery of refrigerant after leakage, the above method further includes: determining whether a refrigerant leakage signal is detected; if so, controlling the microcontroller to output a pulse width modulation wave that meets the current duty cycle to control the operation of the drive chip; if not, controlling the microcontroller to stop outputting the pulse width modulation wave and controlling the drive chip to standby at the lowest power consumption.

[0083] The following detailed explanation of this embodiment is illustrated with a specific example. Figure 5A flowchart of a drive current regulation method according to another embodiment of the present invention is shown below. Figure 5 As shown, the method includes:

[0084] S1 controls the motor to power on and start, and enters the drive current matching program with the valve.

[0085] S2, determine whether the phase of the driving current is consistent with the preset phase; if yes, proceed to step S3; otherwise, proceed to step S4.

[0086] S3, keep the current drive current unchanged, and then execute step S5.

[0087] When the phase of the drive current matches the preset phase, it indicates that the drive current matches the motor model. If the phase of the drive current does not match the preset phase, it indicates that the drive current does not match the motor model, and the drive current needs to be adjusted.

[0088] S4. By adjusting the duty cycle of the PWM wave output by the microcontroller, the drive current is increased or decreased by ΔX based on the initial value until the phase of the drive current is consistent with the preset phase.

[0089] By adjusting the duty cycle of the PWM wave output by the microcontroller, the drive current is continuously changed until the phase of the drive current matches the preset phase, thus completing the matching of the drive current with the motor model.

[0090] S5, initiate the refrigerant leak detection procedure.

[0091] S6, determine whether the refrigerant leakage concentration is greater than the preset threshold; if not, proceed to step S7; if yes, proceed to step S8.

[0092] S7 controls the motor to stop working, and the driver chip switches to a low-power standby state.

[0093] S8 controls the motor's operation, the drive chip switches to the working state, and the microcontroller monitors the refrigerant leakage concentration in real time.

[0094] S9 monitors overvoltage and overcurrent faults and issues a warning message when such faults occur. Example 6

[0095] This embodiment provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the above-described drive current regulation method.

[0096] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0097] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A drive circuit of a motor for controlling opening and closing of a valve provided on an outlet pipe or an inlet pipe of an outdoor unit of an air conditioning system, characterized in that, The driving circuit includes: The driver chip is connected to the phase detection terminal of the motor, each phase of the motor, and the microcontroller; it is used to detect the phase of the drive current of the motor and output the detection signal to the microcontroller. The adjustment circuit has its input terminal connected to the microcontroller and its output terminal connected to the reference voltage input terminal of the driver chip. The microcontroller is used to adjust the duty cycle of the pulse width modulation wave output by the microcontroller according to the phase of the motor drive current, thereby adjusting the reference voltage input to the drive chip, so that the drive chip adjusts the drive current of the motor based on the reference voltage.

2. The driving circuit according to claim 1, characterized in that, The microcontroller includes: The judgment unit is used to determine whether the phase of the driving current is consistent with the preset phase; The first execution unit is used to control the duty cycle of the output pulse width modulation wave to remain unchanged when the phase of the driving current is consistent with the preset phase. The second execution unit is used to adjust the duty cycle of the pulse width modulation wave output by the microcontroller when the phase of the drive current is inconsistent with the preset phase, so as to adjust the drive current of the motor.

3. The drive circuit according to claim 1, characterized by The regulating circuit includes: An optocoupler, wherein the emitter of the internal phototransistor is connected to the reference voltage input terminal of the driver chip through a voltage divider circuit, and the collector of the internal phototransistor is connected to a first voltage source; the anode of the internal light-emitting diode is connected to a second voltage source, and the cathode is connected to the collector of the switching transistor. The switching transistor has its base connected to the microcontroller and its emitter grounded.

4. The drive circuit according to claim 3, characterized in that, The voltage divider circuit includes: A first resistor and a second resistor are connected in series. The first resistor is connected to the emitter of the phototransistor inside the optocoupler, and the second resistor is grounded. The line between the first resistor and the second resistor is connected to the reference voltage input terminal of the driver chip. The first capacitor is connected in parallel across the two ends of the second resistor.

5. The drive circuit according to claim 1, characterized by The driving circuit also includes: A refrigerant detection device, the output of which is connected to the microcontroller, is used to transmit refrigerant leakage signals to the microcontroller; The microcontroller is also used to output the pulse width modulation wave after detecting the refrigerant leakage signal.

6. The drive circuit according to claim 5, characterized in that, The microcontroller also includes: A low-power control terminal, connected to the driver chip, is used to control the driver chip to standby at the lowest power consumption when the refrigerant detection device does not output a refrigerant leakage signal.

7. An air conditioning system comprising a valve provided on an outlet pipe or an inlet pipe of an outdoor unit of the air conditioning system, characterized in that, The air conditioning system further includes the drive circuit according to any one of claims 1 to 6.

8. A driving current adjustment method applied to the driving circuit according to any one of claims 1 to 6, characterized in that, The method includes: Obtain the phase of the motor's drive current; The duty cycle of the pulse width modulation wave output by the microcontroller in the drive circuit is adjusted according to the phase of the drive current of the motor, thereby adjusting the reference voltage input to the drive chip, so that the drive chip adjusts the drive current of the motor based on the reference voltage. The driving chip is connected to the phase detection terminal of the motor, each phase of the motor, and the microcontroller. The driving circuit also includes an adjustment circuit, whose input terminal is connected to the microcontroller and whose output terminal is connected to the reference voltage input terminal of the driving chip.

9. The method of claim 8, wherein, The duty cycle of the pulse width modulation wave output by the microcontroller is adjusted according to the phase of the motor's drive current, including: Determine whether the phase of the driving current is consistent with the preset phase; If so, the duty cycle of the pulse width modulation wave output by the microcontroller remains unchanged; If not, adjust the duty cycle of the pulse width modulation wave output by the microcontroller.

10. The method of claim 9, wherein, Adjusting the duty cycle of the pulse width modulation wave output by the microcontroller includes: Determine the initial value of the motor's drive current and the current adjustment step size; The duty cycle adjustment amount of the pulse width modulation wave is determined according to the current adjustment step size; wherein, the current adjustment step size and the duty cycle adjustment amount satisfy a preset correspondence. The duty cycle of the pulse width modulation wave is increased or decreased according to the duty cycle adjustment amount until the phase of the driving current is consistent with the preset phase.

11. The method of claim 10, wherein, After controlling the duty cycle of the pulse width modulation wave to increase or decrease according to the duty cycle adjustment amount, the method further includes: Determine if the current drive current value has reached the limit. If so, the duty cycle of the pulse width modulation wave is adjusted according to a trend opposite to the current trend, based on the duty cycle corresponding to the initial value of the driving current.

12. The method according to claim 10, characterized in that, After the phase of the driving current is consistent with the preset phase, the method further includes: Determine if a refrigerant leak signal has been detected; If so, the microcontroller is controlled to output a pulse width modulation wave that satisfies the current duty cycle in order to control the operation of the driver chip; If not, the microcontroller is controlled to stop outputting pulse width modulation waves, and the driver chip is controlled to standby at the lowest power consumption.

13. A computer readable storage medium having stored thereon a computer program, characterized in that When the program is executed by the processor, it implements the method as described in any one of claims 8 to 12.

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