Air conditioner control method, air conditioner power supply system and air conditioner

Abstract

The invention discloses an air conditioner control method, an air conditioner power supply system and an air conditioner, the air conditioner control method is applied to the air conditioner power supply system, the air conditioner power supply system comprises a Vienna rectifier module, and the Vienna rectifier module is used for converting alternating current input by an alternating current power supply into direct current so as to output bus voltage and bus midpoint voltage. The air conditioner control method comprises the steps that after a fan in an air conditioner is controlled to be started for preset time according to a starting signal, bus voltage and bus midpoint voltage are obtained; and controlling a Vienna rectifier module to start according to the bus voltage and the bus midpoint voltage to increase the bus midpoint voltage, so that the fan obtains the target voltage. According to the application, the problem of loss caused by immediately starting the Vienna rectifier module after the air conditioner is started can be relieved, and the fan can be ensured to obtain the target voltage and can be normally started to work, so that the power supply stability of the fan is improved, and the fan control stability is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electronics, in particular to an air conditioner control method, an air conditioner power supply system and an air conditioner. BACKGROUND

[0002] At present, the air conditioner uses a three-phase alternating current input power supply rectification and then inverts control scheme for the compressor, and a single-phase power supply rectification and then inverts control scheme for the fan. This scheme topology is complex, needs to separately increase a single-phase power supply, increases many filter rectifier devices, and increases the complexity of the power supply. Therefore, in the current control scheme, the fan is powered by the bus midpoint in the three-phase Vienna topology. However, there is a problem of unstable control based on the bus midpoint in the Vienna topology for powering the fan.

[0003] Therefore, the current technology still needs to be improved and enhanced. SUMMARY

[0004] The present application provides an air conditioner control method, a power supply system and an air conditioner, which can alleviate the problem of unstable control based on the bus midpoint in the Vienna topology for powering the fan.

[0005] The present application provides an air conditioner control method, which is applied to an air conditioner power supply system, the air conditioner power supply system includes a Vienna rectification module, the Vienna rectification module is used to convert alternating current input by an alternating current power supply into direct current to output a bus voltage and a bus midpoint voltage, and the air conditioner control method includes:

[0006] According to the starting signal, the fan in the air conditioner is turned on for a preset time, and then the bus voltage and the bus midpoint voltage are obtained;

[0007] According to the bus voltage and the bus midpoint voltage, the Vienna rectification module is controlled to be turned on to increase the bus midpoint voltage, so that the fan obtains a target voltage.

[0008] In some embodiments, the step of controlling the Vienna rectification module to be turned on according to the bus voltage and the bus midpoint voltage in the air conditioner control method includes:

[0009] The bus midpoint voltage is compared with a first preset threshold value;

[0010] When the bus midpoint voltage is not greater than the first preset threshold value, the Vienna rectification module is controlled to be turned on.

[0011] In some embodiments, the step of controlling the Vienna rectification module to be turned on according to the bus voltage and the bus midpoint voltage in the air conditioner control method includes:

[0012] The voltage difference between the bus voltage and the bus midpoint voltage is obtained;

[0013] the voltage difference is compared with a second preset threshold value;

[0014] When the voltage difference is greater than or equal to the second preset threshold value, the Vienna rectifier module is controlled to be turned on to increase the bus midpoint voltage; wherein the second preset threshold value is greater than the first preset threshold value.

[0015] In some embodiments, the air conditioner control method further comprises:

[0016] After the speed of the fan is reduced to the target speed according to the shutdown signal, the Vienna rectifier module is controlled to be turned off.

[0017] In some embodiments, the step of controlling the Vienna rectifier module to be turned on comprises:

[0018] The Vienna rectifier module is controlled to be turned on according to a first preset frequency.

[0019] In some embodiments, after the step of controlling the Vienna rectifier module to be turned on according to the first preset frequency, the method further comprises:

[0020] The operating power of the compressor in the air conditioner is obtained;

[0021] When the operating power of the compressor is in a first interval, the switching frequency of the Vienna rectifier module is set to a first preset frequency;

[0022] When the operating power of the compressor is in a second interval, the switching frequency of the Vienna rectifier module is set to a second preset frequency; wherein the first preset frequency is less than the second preset frequency, and the operating power in the first interval is less than the operating power in the second interval.

[0023] Embodiments of the present application also provide an air conditioner power supply system, comprising:

[0024] a Vienna rectifier module, the Vienna rectifier module is used for connecting to an alternating current power supply and converting alternating current input by the alternating current power supply into direct current to output a bus midpoint voltage and a bus voltage;

[0025] a fan driving module, the fan driving module is connected to the midpoint voltage output end of the Vienna rectifier module, and the fan driving module is used for supplying power to a fan according to the bus midpoint voltage;

[0026] a compressor driving module, the compressor driving module is connected to the bus voltage output end of the Vienna rectifier module, and the compressor driving module is used for supplying power to a compressor according to the bus voltage;

[0027] a controller, the controller is connected to the Vienna rectifier module, the fan driving module and the compressor driving module respectively, and the controller is used for executing the air conditioner control method described above.

[0028] The air conditioner power supply system in some embodiments further comprises a filtering module, the filtering module is connected with the bus voltage output end of the Vienna rectifier module and the midpoint voltage output end of the Vienna rectifier module respectively; the filtering module is used for filtering the bus midpoint voltage and the bus voltage.

[0029] The air conditioner power supply system in some embodiments comprises a first electrolytic capacitor, a second electrolytic capacitor, a third electrolytic capacitor, a fourth electrolytic capacitor, a first resistor and a second resistor; one end of the first resistor is connected with the bus voltage output end of the Vienna rectifier module, one end of the first electrolytic capacitor and one end of the second electrolytic capacitor are connected with one end of the first resistor, the other end of the first electrolytic capacitor, the other end of the second electrolytic capacitor and the other end of the first resistor are all connected with the midpoint voltage output end of the Vienna rectifier module, one end of the second resistor is connected with the midpoint voltage output end of the Vienna rectifier module, one end of the third electrolytic capacitor and one end of the fourth electrolytic capacitor are both connected with one end of the second resistor, the other end of the third electrolytic capacitor, the other end of the fourth electrolytic capacitor and the other end of the second resistor are all grounded.

[0030] The air conditioner provided by the embodiments of the present application comprises a fan, a compressor and the air conditioner power supply system.

[0031] The air conditioner control method, the air conditioner power supply system and the air conditioner provided by the present application can control the fan to be turned on for a preset time according to a start signal, and then acquire the bus voltage and the bus midpoint voltage. Subsequently, the Vienna rectifier module is controlled to be turned on for voltage boosting according to the bus voltage and the bus midpoint voltage, so as to increase the bus midpoint voltage, so that the fan driving module acquires the target voltage required by the fan to drive the fan to be normally started and work. After the air conditioner is turned on, the fan driving module is correspondingly turned on, but the Vienna rectifier module is not immediately turned on at this time, but is turned on after a preset time, so as to relieve the loss problem existing in the case that the Vienna rectifier module is immediately turned on after the air conditioner is turned on, and to ensure that the fan acquires the target voltage to be normally started and work, thereby improving the stability of power supply to the fan and the stability of control to the fan. BRIEF DESCRIPTION OF DRAWINGS

[0032] The technical solutions and other beneficial effects of the present application will be apparent through the following detailed description of the specific embodiments of the present application in combination with the accompanying drawings.

[0033] Figure 1 The first structural block diagram of the air conditioner power supply system provided by the embodiments of the present application.

[0034] Figure 2 The second structural block diagram of the air conditioner power supply system provided by the embodiments of the present application.

[0035] Figure 3 The circuit diagram of the filter module in the air conditioner power supply system provided by the embodiment of the present application is provided.

[0036] Figure 4 The first flowchart of the air conditioner control method provided by the embodiment of the present application is provided.

[0037] Figure 5 The first flowchart of step 200 in the air conditioner control method provided by the embodiment of the present application is provided.

[0038] Figure 6 The second flowchart of step 200 in the air conditioner control method provided by the embodiment of the present application is provided.

[0039] Figure 7 The second flowchart of the air conditioner control method provided by the embodiment of the present application is provided. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0041] In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features, so the features with "first", "second" can explicitly or implicitly include one or more features, and in the description of the present application, the meaning of "multiple" is two or more, unless otherwise explicitly and specifically limited.

[0042] Please refer to Figure 1 The embodiment of the present application provides an air conditioner power supply system, which comprises a Vienna rectifier module, a fan driving module, a compressor driving module and a controller. The Vienna rectifier module is used for connecting an alternating current power supply, the fan driving module is connected with a midpoint voltage output end (such as the B point in the figure) of the Vienna rectifier module, the compressor driving module is connected with a bus voltage output end (such as the A point in the figure) of the Vienna rectifier module, and the controller is connected with the Vienna rectifier module, the fan driving module and the compressor driving module respectively.

[0043] The Vienna rectifier module is used to convert AC power input AC into DC to output bus midpoint voltage and bus voltage; the fan driving module is used to supply power to the fan according to the bus midpoint voltage, and the compressor driving module is used to supply power to the compressor according to the bus voltage. The controller controls the operating state of the Vienna rectifier module, the fan driving module and the compressor driving module based on the air conditioner control method. In this embodiment, the fan driving module is connected to the bus midpoint position of the Vienna rectifier module, and the bus midpoint voltage is used to provide power to the fan driving module to drive the fan to work. The bus midpoint potential of the Vienna rectifier module is relatively balanced, but if the fan takes power at the bus midpoint position, the bus midpoint voltage will drop rapidly when the air conditioner is turned on, and the bus midpoint voltage will drop to 0V if the Vienna rectifier module is not turned on, thereby causing the midpoint potential of the Vienna rectifier module to be unbalanced and unable to ensure the stability of the fan power supply. However, when the air conditioner is turned on and the fan driving module is turned on, the Vienna rectifier module is immediately turned on, which increases the loss.

[0044] Please refer to Figure 2 In some embodiments, the air conditioner power supply system further comprises a filter module connected to the midpoint voltage output end of the Vienna rectifier module and the bus voltage output end of the Vienna rectifier module; the filter module is used to filter the bus midpoint voltage and the bus voltage, which is beneficial to improve the reliability of the air conditioner power supply system.

[0045] Please refer to Figure 3 As an embodiment, the filter module comprises a first electrolytic capacitor, a second electrolytic capacitor, a third electrolytic capacitor, a fourth electrolytic capacitor, a first resistor and a second resistor; one end of the first resistor is connected to the bus voltage output end of the Vienna rectifier module, one end of the first electrolytic capacitor and one end of the second electrolytic capacitor are connected to one end of the first resistor, the other end of the first electrolytic capacitor, the other end of the second electrolytic capacitor and the other end of the first resistor are all connected to the midpoint voltage output end of the Vienna rectifier module, one end of the second resistor is connected to the midpoint voltage output end of the Vienna rectifier module, one end of the third electrolytic capacitor and one end of the fourth electrolytic capacitor are both connected to one end of the second resistor, the other end of the third electrolytic capacitor, the other end of the fourth electrolytic capacitor and the other end of the second resistor are all grounded. The rated withstand voltage of the electrolytic capacitor in this embodiment can be 450V, of course, other rated withstand voltage electrolytic capacitors can also be selected in other embodiments, which are not limited in this embodiment.

[0046] Please refer to Figure 4 The application also provides an air conditioner control method, which is applied to the air conditioner power supply system described above, and the air conditioner control method comprises the following steps:

[0047] 100, according to the starting signal, control the fan in the air conditioner to be turned on for a preset time, and then obtain the bus voltage and the bus midpoint voltage;

[0048] 200、controlling the Vienna rectifier module to be turned on according to the bus voltage and the bus midpoint voltage to increase the bus midpoint voltage so that the fan obtains a target voltage.

[0049] In this embodiment, after the air conditioner receives a start signal, the controller controls the fan to be turned on (i.e., controls the fan drive module to be turned on) for a preset time according to the start signal, and then obtains the bus voltage and the bus midpoint voltage. Subsequently, the Vienna rectifier module is controlled to be turned on to increase the bus midpoint voltage according to the bus voltage and the bus midpoint voltage, so that the fan drive module obtains a target voltage required by the fan to drive the fan to start working normally. That is, in this embodiment, the fan drive module is turned on by the controller after the air conditioner is turned on, but the Vienna rectifier module is not turned on immediately at this time, but is turned on to increase the voltage after a preset time, so as to alleviate the loss problem existing in the Vienna rectifier module being turned on immediately after the air conditioner is turned on, and to ensure that the fan obtains the target voltage to start working normally, thereby improving the stability of power supply to the fan and the stability of control over the fan.

[0050] Referring to Figure 5 In some embodiments, step 200 includes:

[0051] 210, comparing the bus midpoint voltage with a first preset threshold value;

[0052] 220, when the bus midpoint voltage is not greater than the first preset threshold value, controlling the Vienna rectifier module to be turned on.

[0053] After the air conditioner is started, the fan is controlled to be turned on for a preset time, the bus midpoint voltage is obtained, and the bus midpoint voltage is compared with a first preset threshold value. If the bus midpoint voltage is not greater than the first preset threshold value, i.e., is less than or equal to the first preset threshold value, it indicates that the bus midpoint voltage at this time is insufficient to make the fan drive module control the fan to be turned on. In order to ensure that the fan can start normally, the controller controls the Vienna rectifier module to be turned on to increase the bus voltage and the bus midpoint voltage. In the Vienna rectifier module, six rectifier diodes (such as D1, D2, D3, D4, D5, and D6 in the figure) and six IGBT switches (such as T11, T12, T13, T14, T15, and T16 in the figure) are arranged, and the six IGBT switches form three groups. Controlling the Vienna rectifier module to be turned on means that the controller controls the three groups of IGBT switches to be turned on alternately.

[0054] Referring to Figure 6 In some other embodiments, step 200 includes:

[0055] 201, obtaining a voltage difference between the bus voltage and the bus midpoint voltage;

[0056] 202、compare the voltage difference with a second preset threshold value;

[0057] 203、when the voltage difference is greater than or equal to the second preset threshold value, then control the Vienna rectifier module to be turned on to increase the bus midpoint voltage; wherein the second preset threshold value is greater than the first preset threshold value.

[0058] After the air conditioner is started, the fan is controlled to be turned on for a preset time, the bus midpoint voltage and the bus voltage are obtained, and the voltage difference between the bus voltage and the bus midpoint is calculated. The difference voltage is compared with the second preset threshold value. If the difference voltage is greater than the second preset threshold value, it also indicates that the bus midpoint voltage is too small to enable the fan drive module to control the fan to be turned on at this time. In order to ensure that the fan can be started normally, the Vienna rectifier module can also be controlled to be turned on to raise the bus voltage and the bus midpoint voltage. Specifically, the three groups of IGBT switches in the Vienna rectifier module are alternately controlled to be turned on by the controller.

[0059] In some embodiments, the step of controlling the Vienna rectifier module to be turned on in steps 220 and 203 includes controlling the Vienna rectifier module to be turned on according to a first preset frequency. In this embodiment, the switching frequency of the Vienna rectifier module is set to K, and the first preset frequency can be K / 2. That is, in this embodiment, the Vienna rectifier module is controlled to be turned on at a smaller switching frequency when it is controlled to be turned on, thereby reducing the switching loss of the IGBT and improving energy efficiency.

[0060] Please refer to Figure 7 As an embodiment, after the Vienna rectifier module is controlled to be turned on according to the first preset frequency, it further includes:

[0061] 300、obtain the running power of the compressor in the air conditioner;

[0062] 400、when the running power of the compressor is in a first interval, set the switching frequency of the Vienna rectifier module to a first preset frequency;

[0063] 500、when the running power of the compressor is in a second interval, set the switching frequency of the Vienna rectifier module to a second preset frequency; wherein the first preset frequency is less than the second preset frequency, and the running power in the first interval is less than the running power in the second interval.

[0064] When the air conditioner starts according to the start signal, the compressor driving module is driven to start running by the controller. When the Vienna rectifier module is started, the running power of the compressor in the air conditioner is obtained. If the running power of the compressor is in a smaller first interval, it can be considered that the compressor is in a low-speed running state. At this time, the switching frequency of the Vienna rectifier module is set to a first preset frequency, so that the bus voltage can be controlled at a relatively intermediate value, which is beneficial to reduce the higher loss caused by the higher bus voltage, and at the same time, it can also reduce the switching loss. The smaller switching frequency can also improve the electromagnetic interference and heat dissipation problem. If the running power of the compressor is in a larger second interval, it can be indicated that the compressor is in a high-speed running state. At this time, the influence of switching loss on the overall power is smaller, and the switching frequency of the Vienna rectifier module can be increased to a second preset frequency at this time. The second preset frequency can be relatively larger than the first preset frequency. In the embodiment, the switching frequency is increased, the dynamic effect is improved, and the current ripple is reduced. When the compressor is in a high-speed running state, increasing the switching frequency of the Vienna rectifier module to improve the bus voltage can reduce the compressor current, and reducing the current can reduce the fixed resistance loss and improve the efficiency.

[0065] In some embodiments, the air conditioner control method further comprises: after the speed of the fan is reduced to the target speed according to the shutdown signal, the Vienna rectifier module is controlled to be closed. When the air conditioner is shut down, the controller can reduce the speed of the fan to the target speed such as the lowest gear speed of the fan according to the shutdown signal. Specifically, the controller can reduce the switching frequency of the fan driving module to reduce the speed of the fan. Then, the Vienna rectifier module is controlled to be closed. At present, when the air conditioner is shut down, the compressor is usually closed first, and the fan is maintained at the existing speed for 1 minute before being shut down. In the embodiment, before the compressor and the Vienna rectifier module are closed when the air conditioner is shut down, the speed of the fan is first reduced to the lowest gear before being shut down, which can prevent the speed of the fan from being too high. After the PFC is closed, the bus midpoint voltage drops too much and too fast, thereby causing the voltage of the electrolytic capacitor in the filter module to be too large and having the risk of overvoltage.

[0066] To further illustrate the air conditioning control method in this embodiment, the following specific examples illustrate the air conditioning control method: The maximum voltage of the air conditioning power system is set to 750V, so the busbar midpoint voltage is a maximum of 350V. The busbar voltage is set to V, the busbar midpoint voltage is set to V0, the electrolytic capacitor's withstand voltage protection value is set to 420 (leaving a 30V margin for an electrolytic capacitor rated at 450V), and the switching frequency of the IGBT switch in the Vienna rectifier module is set to K. The rated voltage of the fan is set to DC 310V. When the busbar midpoint voltage V0, which supplies power to the fan, is ≤100V, the fan stops immediately; when the busbar voltage V is ≤150V, the fan is running at its lowest speed. When the air conditioner is started: the fan is generally turned on for 30 seconds before the compressor is turned on. Before the Vienna rectifier module is turned on, assuming the three-phase AC power input is 380V and the busbar voltage is 514V, the busbar midpoint voltage is 257V. Regarding the air conditioning control method, when the fan is turned on (i.e., the fan driver module is turned on), the bus midpoint voltage drops rapidly. If the preset time after the fan is turned on is t1, and the bus midpoint voltage is V1 after the preset time, if V-V1 ≥ 420V or V1 ≤ 100V, the controller controls the Vienna rectifier module to turn on. That is, the three IGBTs in the Vienna circuit are alternately turned on, raising the bus voltage and the bus midpoint voltage, clamping the voltage on the electrolytic capacitor to 350V.

[0067] The present application also provides an air conditioner, comprising a fan, a compressor, and the aforementioned air conditioning power system. The air conditioning power system is connected to the fan and the compressor, and the fan and the compressor are driven by the air conditioning power system. Since the air conditioning power system has been described in detail above, it will not be further described here.

[0068] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0069] The above is a detailed introduction to the air-conditioning control method provided in the embodiments of the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the technical solutions and core ideas of the present application. Ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents. These modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. An air conditioning control method, characterized in that: The air conditioning control method is applied to an air conditioning power supply system, wherein the air conditioning power supply system includes a Vienna rectifier module, wherein the Vienna rectifier module is used to convert AC power input from an AC power supply into DC power to output a bus voltage and a bus midpoint voltage. The air conditioning control method includes: After controlling the fan in the air conditioner to start for a preset time according to the start signal, obtaining the bus voltage and the bus midpoint voltage; The Vienna rectifier module is controlled to be turned on according to the bus voltage and the bus midpoint voltage to increase the bus midpoint voltage so that the wind turbine obtains the target voltage.

2. The air conditioning control method according to claim 1, characterized in that: The step of controlling the Vienna rectifier module to start according to the bus voltage and the bus midpoint voltage includes: Comparing the busbar midpoint voltage with a first preset threshold; When the bus midpoint voltage is not greater than the first preset threshold, the Vienna rectifier module is controlled to turn on.

3. The air conditioning control method according to claim 2, characterized in that: The step of controlling the Vienna rectifier module to start according to the bus voltage and the bus midpoint voltage includes: Obtaining a voltage difference between the bus voltage and the bus midpoint voltage; comparing the voltage difference with a second preset threshold; When the voltage difference is greater than or equal to the second preset threshold, the Vienna rectifier module is controlled to turn on to increase the bus neutral point voltage; wherein the second preset threshold is greater than the first preset threshold.

4. The air conditioning control method according to any one of claims 1 to 3, characterized in that: The air conditioning control method further includes: After the rotation speed of the fan is reduced to the target rotation speed according to the shutdown signal, the Vienna rectifier module is controlled to be shut down.

5. The air conditioning control method according to claim 2 or 3, characterized in that: The step of controlling the Vienna rectifier module to start includes: The Vienna rectifier module is controlled to start according to the first preset frequency.

6. The air conditioning control method according to claim 5, characterized in that: After the step of controlling the Vienna rectifier module to start according to the first preset frequency, the following steps are further included: Obtaining the operating power of the compressor in the air conditioner; When the operating power of the compressor is in the first interval, the switching frequency of the Vienna rectifier module is set to the first preset frequency; When the operating power of the compressor is in the second interval, the switching frequency of the Vienna rectifier module is set to a second preset frequency; wherein the first preset frequency is less than the second preset frequency, and the operating power in the first interval is less than the operating power in the second interval.

7. An air conditioning power supply system, characterized in that: The air conditioning power supply system includes: A Vienna rectifier module, which is used to connect to an AC power supply and convert the AC power input by the AC power supply into DC power to output a bus midpoint voltage and a bus voltage; A fan drive module, the fan drive module is connected to the midpoint voltage output terminal of the Vienna rectifier module, and the fan drive module is used to power the fan according to the bus midpoint voltage; A compressor drive module, the compressor drive module is connected to the bus voltage output end of the Vienna rectifier module, and the compressor drive module is used to power the compressor according to the bus voltage; A controller, wherein the controller is respectively connected to the Vienna rectifier module, the fan drive module and the compressor drive module, and the controller is used to execute the air conditioning control method according to any one of claims 1 to 6.

8. The air conditioning power supply system according to claim 7, characterized in that: The air conditioning power supply system also includes a filtering module, which is respectively connected to the midpoint voltage output end of the Vienna rectifier module and the bus voltage output end of the Vienna rectifier module; the filtering module is used to filter the bus midpoint voltage and the bus voltage.

9. The air conditioning power supply system according to claim 8, characterized in that: The filtering module includes a first electrolytic capacitor, a second electrolytic capacitor, a third electrolytic capacitor, a fourth electrolytic capacitor, a first resistor and a second resistor; one end of the first resistor is connected to the bus voltage output end of the Vienna rectifier module, one end of the first electrolytic capacitor and one end of the second electrolytic capacitor are connected to one end of the first resistor, the other end of the first electrolytic capacitor, the other end of the second electrolytic capacitor and the other end of the first resistor are all connected to the midpoint voltage output end of the Vienna rectifier module, one end of the second resistor is connected to the midpoint voltage output end of the Vienna rectifier module, one end of the third electrolytic capacitor and one end of the fourth electrolytic capacitor are both connected to one end of the second resistor, and the other end of the third electrolytic capacitor, the other end of the fourth electrolytic capacitor and the other end of the second resistor are all grounded.

10. An air conditioner, characterized in that: The air conditioner includes a fan, a compressor and an air conditioning power supply system as described in any one of claims 7 to 9.

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