Air conditioner and control method

Abstract

The present invention discloses an air conditioner and a control method. The controller of the air conditioner is configured to determine a voltage monitoring result based on monitoring the AC input voltage before the rectifier and the DC bus voltage at both ends of the capacitor; and control the relay according to the voltage monitoring result; wherein the voltage monitoring result includes a first voltage value corresponding to the AC input voltage, and a second voltage value and a voltage change rate corresponding to the DC bus voltage, thereby effectively controlling the impact current when an abnormal voltage condition occurs, thereby improving the reliability of the hardware circuit.

Description

Technical Field

[0001] The present application relates to the field of air conditioning control, and more specifically, to an air conditioner and a control method. Background Art

[0002] like Figure 1 The figure shows an air conditioner anti-inrush current protection circuit under a single-phase power supply in the prior art. The logic of the circuit is that the AC mains passes through a current limiting resistor, is then rectified to become a pulsating DC power, and then is filtered by an electrolytic capacitor to output a smooth DC power to the subsequent load. The general control timing is that when the power is just turned on, the relay K1 is not attracted, and the electrolytic capacitor is first charged through the current limiting resistor. After time t1, when the charging current is almost 0, the control closes the relay K1. At this time, the voltage difference across the relay contacts is relatively small, so the charging current passing through is also relatively small. This is the working principle of a typical anti-inrush current protection circuit.

[0003] However, the above control sequence only considers the situation of normal power supply, but does not consider the situation of abnormal grid voltage, especially when the voltage drops and sags temporarily. If there is no special timing control and protection method after the relay is closed, the voltage will suddenly recover, which will cause a large impact current to flow through the relay K1, the rectifier silicon bridge, and the fuse, causing the device to be damaged by short-term overcurrent, making the product unable to work normally and causing user complaints.

[0004] Therefore, how to provide an air conditioner that can effectively control the impact current when an abnormal voltage condition occurs in the air conditioner is a technical problem that needs to be solved at present. Summary of the invention

[0005] The present invention provides an air conditioner, which is used to solve the technical problem in the prior art that the impact current cannot be effectively controlled when an abnormal voltage condition occurs in the air conditioner.

[0006] In some embodiments of the present application, the air conditioner comprises:

[0007] The refrigerant circulation loop allows the refrigerant to circulate in a loop consisting of a compressor, a condenser, an expansion valve, an evaporator, a four-way valve and a pressure reducer;

[0008] The compressor is used to compress the low-temperature and low-pressure refrigerant gas into high-temperature and high-pressure refrigerant gas and discharge it to the condenser;

[0009] An outdoor heat exchanger and an indoor heat exchanger, one of which works as a condenser and the other works as an evaporator;

[0010] An anti-inrush current protection circuit comprises a current limiting resistor, a relay, a rectifier, a capacitor, a switching power supply and an IPM, wherein the current limiting resistor is connected in series between one end of an AC input power supply and a first input end of the rectifier, the relay is connected in parallel with the current limiting resistor, the first output end of the rectifier and the second output end of the rectifier are connected to the capacitor, the IPM and the switching power supply respectively, and the switching power supply is also connected to the IPM;

[0011] The controller is configured to include:

[0012] Determining a voltage monitoring result based on monitoring the AC input voltage before the rectifier and the DC bus voltage across the capacitor;

[0013] controlling the relay according to the voltage monitoring result;

[0014] The voltage monitoring result includes a first voltage value corresponding to the AC input voltage, and a second voltage value and a voltage change rate corresponding to the DC bus voltage.

[0015] In some embodiments of the present application, the controller is specifically configured as follows:

[0016] If the anti-inrush current protection circuit enters the first mode and maintains the first preset time, turning off the relay or maintaining the relay in the disconnected state;

[0017] Among them, the first mode includes that the first voltage value is not less than a first preset threshold, or the second voltage value is not less than a second preset threshold, or the first voltage value is not greater than a third preset threshold, or the second voltage value is not greater than a fourth preset threshold.

[0018] In some embodiments of the present application, the controller is further configured to:

[0019] If the anti-inrush current protection circuit enters the second mode and the relay is in the off state, delaying the second preset time to close the relay;

[0020] The second mode is that the first voltage value is not greater than a fifth preset threshold, the second voltage value is not greater than a sixth preset threshold, the first voltage value is not less than a seventh preset threshold, and the second voltage value is not less than an eighth preset threshold.

[0021] In some embodiments of the present application, the controller is further configured to:

[0022] If the anti-inrush current protection circuit enters the third mode, the relay is turned off or maintained in an off state, and an alarm of a DC voltage sudden change fault is issued;

[0023] If the DC voltage mutation fault disappears after the anti-inrush current protection circuit enters the third mode for a third preset time, the relay is closed for a second preset time delay;

[0024] Among them, the third mode is that the voltage change rate exceeds a preset conversion rate threshold.

[0025] In some embodiments of the present application, the controller is further configured to:

[0026] If the anti-inrush current protection circuit enters the first mode and maintains the fourth preset time, an alarm of abnormal voltage fault is issued;

[0027] If the anti-inrush current protection circuit enters the second mode, it is determined whether the abnormal voltage fault exists according to the monitoring result.

[0028] Corresponding to the air conditioner in the embodiment of the present application, the present application also proposes an air conditioner control method, which is applied to an air conditioner including a refrigerant circulation loop, a compressor, an outdoor heat exchanger, an indoor heat exchanger, an anti-surge current protection circuit and a controller.

[0029] In some embodiments of the present application, the method includes:

[0030] Determining a voltage monitoring result based on monitoring an AC input voltage before the rectifier and a DC bus voltage across the capacitor;

[0031] controlling the relay according to the voltage monitoring result;

[0032] The voltage monitoring result includes a first voltage value corresponding to the AC input voltage, and a second voltage value and a voltage change rate corresponding to the DC bus voltage.

[0033] In some embodiments of the present application, the relay is controlled according to the voltage monitoring result, specifically:

[0034] If the anti-inrush current protection circuit enters the first mode and maintains the first preset time, turning off the relay or maintaining the relay in the disconnected state;

[0035] Among them, the first mode includes that the first voltage value is not less than a first preset threshold, or the second voltage value is not less than a second preset threshold, or the first voltage value is not greater than a third preset threshold, or the second voltage value is not greater than a fourth preset threshold.

[0036] In some embodiments of the present application, the method further includes:

[0037] If the anti-inrush current protection circuit enters the second mode and the relay is in the off state, delaying the second preset time to close the relay;

[0038] The second mode is that the first voltage value is not greater than a fifth preset threshold, the second voltage value is not greater than a sixth preset threshold, the first voltage value is not less than a seventh preset threshold, and the second voltage value is not less than an eighth preset threshold.

[0039] In some embodiments of the present application, the method further includes:

[0040] If the anti-inrush current protection circuit enters the third mode, the relay is turned off or maintained in an off state, and an alarm of a DC voltage sudden change fault is issued;

[0041] If the DC voltage mutation fault disappears after the anti-inrush current protection circuit enters the third mode for a third preset time, the relay is closed for a second preset time delay;

[0042] Among them, the third mode is that the voltage change rate exceeds a preset conversion rate threshold.

[0043] In some embodiments of the present application, the method further includes:

[0044] If the anti-inrush current protection circuit enters the first mode and maintains the fourth preset time, an alarm of abnormal voltage fault is issued;

[0045] If the anti-inrush current protection circuit enters the second mode, it is determined whether the abnormal voltage fault exists according to the monitoring result.

[0046] By applying the above technical scheme, the voltage monitoring result is determined based on monitoring the AC input voltage before the rectifier and the DC bus voltage at both ends of the capacitor; the relay is controlled according to the voltage monitoring result; wherein the voltage monitoring result includes a first voltage value corresponding to the AC input voltage, and a second voltage value and a voltage change rate corresponding to the DC bus voltage, so that when voltage abnormalities such as voltage drop and temporary sag and recovery occur, the relay is turned off or kept in a disconnected state. Due to the current limiting effect of the current limiting resistor, the capacitor charging current can be prevented from being too large, thereby avoiding the problem of electronic components in the air conditioner being damaged by large current, thereby ensuring the normal, safe, stable and reliable operation of the air conditioner. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0048] Figure 1 The schematic diagram of the air conditioner anti-inrush current protection circuit in the case of single-phase power supply in the prior art is shown.

[0049] Figure 2 It is a perspective view showing the appearance of the air conditioner according to the embodiment.

[0050] Figure 3 1 is a circuit diagram schematically showing the structure of the air conditioner according to the embodiment.

[0051] Figure 4 A schematic flow chart of an air conditioner control method in an embodiment of the present invention is shown.

[0052] Description of symbols

[0053] 1: air conditioner; 2: outdoor unit; 3: indoor unit; 10: refrigerant circuit; 11: compressor; 12: four-way valve; 13: outdoor heat exchanger;

[0054] 14: Expansion valve; 16: Indoor heat exchanger; 21: Outdoor fan; 31: Indoor fan; 32: Indoor temperature sensor; 33: Indoor heat exchanger temperature sensor;

[0055] 63: vertical baffle; 64, 65: horizontal baffle DETAILED DESCRIPTION

[0056] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0057] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0058] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0059] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0060] The air conditioner in this application performs a refrigeration cycle of the air conditioner by using a compressor, a condenser, an expansion valve and an evaporator. The refrigeration cycle includes a series of processes involving compression, condensation, expansion and evaporation, and supplies refrigerant to the air that has been conditioned and heat-exchanged.

[0061] The compressor compresses the refrigerant gas in a high temperature and high pressure state and discharges the compressed refrigerant gas. The discharged refrigerant gas flows into the condenser. The condenser condenses the compressed refrigerant into a liquid phase, and the heat is released to the surrounding environment through the condensation process.

[0062] The expansion valve expands the high-temperature and high-pressure liquid refrigerant condensed in the condenser into a low-pressure liquid refrigerant. The evaporator evaporates the refrigerant expanded in the expansion valve and returns the refrigerant gas in a low-temperature and low-pressure state to the compressor. The evaporator can achieve a refrigeration effect by utilizing the latent heat of evaporation of the refrigerant to exchange heat with the material to be cooled. In the entire cycle, the air conditioner can adjust the temperature of the indoor space.

[0063] The outdoor unit of the air conditioner refers to a portion of a refrigeration cycle including a compressor and an outdoor heat exchanger, the indoor unit of the air conditioner includes an indoor heat exchanger, and an expansion valve may be provided in the indoor unit or the outdoor unit.

[0064] The indoor heat exchanger and the outdoor heat exchanger function as a condenser or an evaporator. When the indoor heat exchanger functions as a condenser, the air conditioner functions as a heater in a heating mode, and when the indoor heat exchanger functions as an evaporator, the air conditioner functions as a cooler in a cooling mode.

[0065] Figure 2The air conditioner 1 shown has: an indoor unit 3, taking an indoor wall mounted unit (shown in the figure) as an example, the indoor wall mounted unit is usually installed on an indoor wall surface WL, etc. For another example, an indoor cabinet unit (not shown in the figure) is also a form of an indoor unit.

[0066] The outdoor unit 2 is usually installed outdoors and is used for heat exchange in the indoor environment. Figure 1 In the figure, since the outdoor unit 2 is located outdoors on the opposite side to the indoor unit 3 across the wall surface WL, the outdoor unit 2 is indicated by a dotted line.

[0067] Figure 3 , the circuit structure of the air conditioner 1 is shown in the figure. The air conditioner 1 is provided with a refrigerant circuit 10. By circulating the refrigerant in the refrigerant circuit 10, a vapor compression refrigeration cycle can be performed. The indoor unit 3 and the outdoor unit 2 are connected using a connecting pipe 4 to form a refrigerant circuit 10 for circulating the refrigerant. The refrigerant circuit 10 is provided with a compressor 11, an outdoor heat exchanger 13, an expansion valve 14, a liquid storage tank 15 and an indoor heat exchanger 16. Among them, the indoor heat exchanger 16 and the outdoor heat exchanger 13 work as a condenser or an evaporator. The compressor 11 sucks in the refrigerant from the suction port and discharges the refrigerant compressed inside to the indoor heat exchanger 16 from the discharge port. The compressor 11 is a variable capacity inverter compressor that performs speed control based on the inverter, and the four-way valve 12 switches between heating and cooling.

[0068] The outdoor heat exchanger 13 has a first inlet and outlet for allowing the refrigerant to flow between the compressor 11 and the suction port via the accumulator 15, and has a second inlet and outlet for allowing the refrigerant to flow between the expansion valve 14. The outdoor heat exchanger 13 performs heat exchange between the refrigerant flowing in a heat transfer pipe (not shown) connected between the second inlet and outlet of the outdoor heat exchanger 13 and the first inlet and outlet and the outdoor air.

[0069] The expansion valve 14 is arranged between the outdoor heat exchanger 13 and the indoor heat exchanger 16. The expansion valve 14 has a function of expanding and reducing the pressure of the refrigerant flowing between the outdoor heat exchanger 13 and the indoor heat exchanger 16. The expansion valve 14 is configured to be able to change the opening degree. By reducing the opening degree, the flow resistance of the refrigerant passing through the expansion valve 14 is increased, and by increasing the opening degree, the flow resistance of the refrigerant passing through the expansion valve 14 is reduced. Such an expansion valve 14 expands and reduces the pressure of the refrigerant flowing from the indoor heat exchanger 16 toward the outdoor heat exchanger 13 during the heating operation. In addition, even if the states of other devices installed in the refrigerant circuit 10 do not change, when the opening degree of the expansion valve 14 changes, the flow rate of the refrigerant flowing in the refrigerant circuit 10 will also change.

[0070] The indoor heat exchanger 16 has a second inlet and outlet for allowing liquid refrigerant to flow between the expansion valve 14 and the indoor heat exchanger 16, and has a first inlet and outlet for allowing gas refrigerant to flow between the discharge port of the compressor 11. The indoor heat exchanger 16 has a heat transfer pipe 16B (see FIG. 1 ) connected between the second inlet and outlet and the first inlet of the indoor heat exchanger 16. Figure 3 ) exchanges heat with the indoor air.

[0071] The accumulator 15 is arranged between the outdoor heat exchanger 13 and the suction port of the compressor 11. The refrigerant flowing from the outdoor heat exchanger 13 to the compressor 11 is separated into gas refrigerant and liquid refrigerant in the accumulator 15. And, the gas refrigerant is mainly supplied from the accumulator 15 to the suction port of the compressor 11.

[0072] The outdoor unit 2 further includes an outdoor fan 21, which generates an airflow of outdoor air passing through the outdoor heat exchanger 13 to promote heat exchange between the refrigerant flowing in the heat transfer tube and the outdoor air. The outdoor fan 21 is driven by an outdoor fan motor 21A whose rotation speed can be changed. In addition, the indoor unit 3 includes an indoor fan 31, which generates an airflow of indoor air passing through the indoor heat exchanger 16 to promote heat exchange between the refrigerant flowing in the heat transfer tube 16B and the indoor air. The indoor fan 31 is driven by an indoor fan motor 31A whose rotation speed can be changed.

[0073] The air conditioner of the embodiment of the present invention further comprises an anti-surge current protection circuit, such as Figure 1 As shown, it includes a current limiting resistor, a relay, a rectifier, a capacitor, a switching power supply and an IPM, wherein the current limiting resistor is connected in series between one end of the AC input power supply and the first input end of the rectifier, the relay is connected in parallel with the current limiting resistor, the first output end of the rectifier and the second output end of the rectifier are respectively connected to the capacitor, the IPM (Intelligent Power Module) and the switching power supply, and the switching power supply is also connected to the IPM.

[0074] The embodiment of the present invention determines the voltage monitoring result based on monitoring the AC input voltage before the rectifier and the DC bus voltage at both ends of the capacitor; controls the relay according to the voltage monitoring result, thereby effectively controlling the impact current when an abnormal voltage occurs, thereby improving the reliability of the hardware circuit.

[0075] The following describes the process of controlling the inrush current in the embodiment of the present application.

[0076] The definition is as follows:

[0077] AC: AC input voltage;

[0078] DC: rectified DC bus voltage (voltage across the smoothing filter electrolytic capacitor)

[0079] 1. K1 relay control:

[0080] 1. At any time (power-on, standby, or operation), if any of the following conditions is met:

[0081] 1) AC>=X1 V

[0082] 2) DC>=Y1 V

[0083] 3) AC <= X2 V

[0084] 4) DC <= Y2 V

[0085] And maintain 100mS, then:

[0086] 1) If the relay K1 is turned off, it will remain in the off state;

[0087] 2) The closed relay K1 is immediately turned off.

[0088] 2. At any time (power-on, standby, operation), if any of the following conditions are met at the same time:

[0089] 1) AC <= X3 V

[0090] 2) DC <= Y3 V

[0091] 3)AC>=X4 V

[0092] 4) DC>=Y4 V

[0093] Then: after 3S, close relay K1.

[0094] 3. If a DC voltage mutation (increase or decrease) is detected at any time (standby or operation), a DC voltage mutation fault will be reported:

[0095] 1) If the relay K1 is turned off, it will remain in the off state;

[0096] 2) The closed relay K1 is immediately turned off.

[0097] 3) Clear the fault after 2 minutes and check whether the DC voltage mutation fault exists. At this time:

[0098] If there is still a DC voltage sudden change fault, continue to perform steps 1), 2), and 3);

[0099] If there is no DC voltage sudden change fault, relay K1 will be closed after 3S.

[0100] 2. Voltage protection control:

[0101] 1. At any time (power-on, standby, or operation), if any of the following conditions is met:

[0102] 1) AC>=X1 V

[0103] 2) DC>=Y1 V

[0104] 3) AC <= X2 V

[0105] 4) DC <= Y2 V

[0106] If it maintains for 5S, it will report abnormal voltage fault and handle it according to the fault method.

[0107] 2. At any time (power-on, standby, operation), if any of the following conditions are met at the same time:

[0108] 1) AC <= X3 V

[0109] 2) DC <= Y3 V

[0110] 3)AC>=X4 V

[0111] 4) DC>=Y4 V

[0112] Then: Clear the fault and check whether the abnormal voltage fault exists.

[0113] By applying the above technical scheme, the voltage monitoring result is determined based on monitoring the AC input voltage before the rectifier and the DC bus voltage at both ends of the capacitor; the relay is controlled according to the voltage monitoring result; wherein the voltage monitoring result includes a first voltage value corresponding to the AC input voltage, and a second voltage value and a voltage change rate corresponding to the DC bus voltage, so that when voltage abnormalities such as voltage drop and temporary sag and recovery occur, the relay is turned off or kept in a disconnected state. Due to the current limiting effect of the current limiting resistor, the capacitor charging current can be prevented from being too large, thereby avoiding the problem of electronic components in the air conditioner being damaged by large current, thereby ensuring the normal, safe, stable and reliable operation of the air conditioner.

[0114] Corresponding to the air conditioner in the embodiment of the present application, the embodiment of the present application also proposes an air conditioner control method, which is applied to an air conditioner including a refrigerant circulation loop, a compressor, an outdoor heat exchanger, an indoor heat exchanger, an anti-surge current protection circuit and a controller, such as Figure 4 As shown, the method includes:

[0115] Step S401, determining a voltage monitoring result based on monitoring the AC input voltage before the rectifier and the DC bus voltage across the capacitor.

[0116] Specifically, the AC input voltage before the rectifier and the DC bus voltage across the capacitor can be monitored by a voltage transformer or a voltage monitoring circuit to determine a voltage monitoring result, which includes a first voltage value corresponding to the AC input voltage, and a second voltage value and a voltage change rate corresponding to the DC bus voltage.

[0117] Step S402: controlling the relay according to the voltage monitoring result.

[0118] Specifically, it is possible to determine whether an abnormal voltage occurs in the anti-inrush current protection circuit based on the voltage monitoring result, and then control the relay.

[0119] In order to effectively limit the impact current when the voltage is too high or too low, in a preferred embodiment of the present application, the relay is controlled according to the voltage monitoring result, specifically:

[0120] If the anti-inrush current protection circuit enters the first mode and maintains the first preset time, turning off the relay or maintaining the relay in the disconnected state;

[0121] Among them, the first mode includes that the first voltage value is not less than a first preset threshold, or the second voltage value is not less than a second preset threshold, or the first voltage value is not greater than a third preset threshold, or the second voltage value is not greater than a fourth preset threshold.

[0122] As described above, by turning off the relay or maintaining the relay in an off state when the voltage is too high or too low, the inrush current is effectively controlled.

[0123] Since there may be a large inrush current when the voltage returns to normal, in order to prevent the inrush current from entering the circuit, in a preferred embodiment of the present application, the method further includes:

[0124] If the anti-inrush current protection circuit enters the second mode and the relay is in the off state, delaying the second preset time to close the relay;

[0125] The second mode is that the first voltage value is not greater than a fifth preset threshold, the second voltage value is not greater than a sixth preset threshold, the first voltage value is not less than a seventh preset threshold, and the second voltage value is not less than an eighth preset threshold.

[0126] As described above, by delaying the second preset time length and then closing the relay when the voltage returns to normal, the inrush current is prevented from entering the circuit.

[0127] When the DC bus voltage suddenly changes, a surge current may also be generated. To avoid the impact of the surge current on the circuit at this time, in a preferred embodiment of the present application, the method further includes:

[0128] If the anti-inrush current protection circuit enters the third mode, the relay is turned off or maintained in an off state, and an alarm of a DC voltage sudden change fault is issued;

[0129] If the DC voltage sudden change fault disappears after the anti-inrush current protection circuit enters the third mode for a third preset time, the relay is closed after a delay of the second preset time.

[0130] Among them, the third mode is that the voltage change rate exceeds a preset conversion rate threshold.

[0131] Specifically, by turning off the relay or maintaining the relay in the disconnected state when the DC bus voltage suddenly changes, and issuing an alarm for a DC voltage sudden change fault, the inrush current is prevented from entering the circuit, and the user is prompted to handle the fault. Accordingly, after the DC bus voltage suddenly changes, a third preset time is delayed to check whether the DC voltage sudden change fault still exists. If not, the relay is closed for the second preset time to avoid the impact of the inrush current when the voltage recovers; otherwise, the relay is turned off or maintained in the disconnected state.

[0132] In order to more effectively prevent the impact current, in a preferred embodiment of the present application, the method further includes:

[0133] If the anti-inrush current protection circuit enters the first mode and maintains the fourth preset time, an alarm of abnormal voltage fault is issued;

[0134] If the anti-inrush current protection circuit enters the second mode, it is determined whether the abnormal voltage fault exists according to the monitoring result.

[0135] As described above, when the anti-inrush current protection circuit reaches the fourth preset time in the first mode, an alarm of abnormal voltage fault is issued to remind the user to deal with it in time. If the anti-inrush current protection circuit enters the second mode, that is, the voltage returns to normal, the AC input voltage and DC bus voltage will continue to be monitored to determine the voltage monitoring results, and it is judged whether the abnormal voltage fault still exists based on the voltage monitoring results, thereby further limiting the inrush current.

[0136] It should be noted that those skilled in the art can determine the preset threshold value and preset duration of the above-mentioned voltage according to actual conditions, which does not affect the protection scope of the present application.

[0137] By applying the above technical scheme, in an air conditioner including a refrigerant circulation loop, a compressor, an outdoor heat exchanger, an indoor heat exchanger, an anti-inrush current protection circuit and a controller, a voltage monitoring result is determined based on monitoring the AC input voltage before the rectifier and the DC bus voltage at both ends of the capacitor; the relay is controlled according to the voltage monitoring result; wherein the voltage monitoring result includes a first voltage value corresponding to the AC input voltage, and a second voltage value and a voltage change rate corresponding to the DC bus voltage, so that when voltage abnormalities such as voltage drop and temporary sag and recovery occur, the relay is turned off or the relay is kept in a disconnected state, and due to the current limiting effect of the current limiting resistor, the capacitor charging current can be prevented from being too large, thereby avoiding the problem of electronic components in the air conditioner being damaged by large current, and ensuring the normal, safe, stable and reliable operation of the air conditioner.

[0138] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements 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 application.

Claims

1. An air conditioner, characterized in that: The air conditioner comprises: The refrigerant circulation loop allows the refrigerant to circulate in a loop consisting of a compressor, a condenser, an expansion valve, an evaporator, a four-way valve and a pressure reducer; The compressor is used to compress the low-temperature and low-pressure refrigerant gas into high-temperature and high-pressure refrigerant gas and discharge it to the condenser; An outdoor heat exchanger and an indoor heat exchanger, one of which works as a condenser and the other works as an evaporator; An anti-inrush current protection circuit comprises a current limiting resistor, a relay, a rectifier, a capacitor, a switching power supply and an intelligent power module IPM, wherein the current limiting resistor is connected in series between one end of an AC input power supply and a first input end of the rectifier, the relay is connected in parallel with the current limiting resistor, the first output end of the rectifier and the second output end of the rectifier are connected to the capacitor, the IPM and the switching power supply respectively, and the switching power supply is also connected to the IPM; The controller is configured to include: Determining a voltage monitoring result based on monitoring the AC input voltage before the rectifier and the DC bus voltage across the capacitor; controlling the relay according to the voltage monitoring result; The voltage monitoring result includes a first voltage value corresponding to the AC input voltage, and a second voltage value and a voltage change rate corresponding to the DC bus voltage; The controller is also configured to: If the anti-inrush current protection circuit enters the second mode and the relay is in the off state, delaying the second preset time to close the relay; The second mode is that the first voltage value is not greater than a fifth preset threshold, the second voltage value is not greater than a sixth preset threshold, the first voltage value is not less than a seventh preset threshold, and the second voltage value is not less than an eighth preset threshold; If the anti-inrush current protection circuit enters the third mode, the relay is turned off or maintained in an off state, and an alarm of a DC voltage sudden change fault is issued; If the DC voltage mutation fault disappears after the anti-inrush current protection circuit enters the third mode for a third preset time, the relay is closed for a second preset time delay; Wherein, the third mode is that the voltage change rate exceeds a preset conversion rate threshold; The controller is specifically configured as follows: If the anti-inrush current protection circuit enters the first mode and maintains the first preset time, turning off the relay or maintaining the relay in the disconnected state; The first mode includes that the first voltage value is not less than a first preset threshold, or the second voltage value is not less than a second preset threshold, or the first voltage value is not greater than a third preset threshold, or the second voltage value is not greater than a fourth preset threshold; If the anti-inrush current protection circuit enters the first mode and maintains the fourth preset time, an alarm of abnormal voltage fault is issued; If the anti-inrush current protection circuit enters the second mode, it is determined whether the abnormal voltage fault exists according to the monitoring result.

2. An air conditioner control method, applied to the air conditioner as claimed in claim 1, characterized in that: The method is applied to an air conditioner including a refrigerant circulation loop, a compressor, an outdoor heat exchanger, an indoor heat exchanger, an anti-inrush current protection circuit and a controller, and the method includes: Determining a voltage monitoring result based on monitoring the AC input voltage before the rectifier and the DC bus voltage across the capacitor; controlling the relay according to the voltage monitoring result; The voltage monitoring result includes a first voltage value corresponding to the AC input voltage, and a second voltage value and a voltage change rate corresponding to the DC bus voltage; If the anti-inrush current protection circuit enters the second mode and the relay is in the off state, delaying the second preset time to close the relay; The second mode is that the first voltage value is not greater than a fifth preset threshold, the second voltage value is not greater than a sixth preset threshold, the first voltage value is not less than a seventh preset threshold, and the second voltage value is not less than an eighth preset threshold; If the anti-inrush current protection circuit enters the third mode, the relay is turned off or maintained in an off state, and an alarm of a DC voltage sudden change fault is issued; If the DC voltage mutation fault disappears after the anti-inrush current protection circuit enters the third mode for a third preset time, the relay is closed for a second preset time delay; Wherein, the third mode is that the voltage change rate exceeds a preset conversion rate threshold; Controlling the relay according to the voltage monitoring result is specifically as follows: If the anti-inrush current protection circuit enters the first mode and maintains the first preset time, turning off the relay or maintaining the relay in the disconnected state; The first mode includes that the first voltage value is not less than a first preset threshold, or the second voltage value is not less than a second preset threshold, or the first voltage value is not greater than a third preset threshold, or the second voltage value is not greater than a fourth preset threshold. If the anti-inrush current protection circuit enters the first mode and maintains the fourth preset time, an alarm of abnormal voltage fault is issued; If the anti-inrush current protection circuit enters the second mode, it is determined whether the abnormal voltage fault exists according to the monitoring result.

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