Washing machine control circuit and washing machine

Abstract

The utility model discloses a washing machine control circuit and a washing machine, and the washing machine control circuit comprises a power input interface which comprises a live line terminal and a zero line terminal; a main control unit; a door lock switch; a rectifying circuit; the door lock detection circuit comprises a voltage division circuit, a first filter capacitor and a switching circuit; one end of the door lock switch is grounded through the voltage division circuit, a voltage division node of the voltage division circuit is connected with one end of the first filter capacitor, the other end of the first filter capacitor is connected with a control end of the switching circuit, and a switching path of the switching circuit is connected with the main control unit. According to the washing machine control circuit and the washing machine, the rectifying circuit is used for charging the first charging capacitor and the second charging capacitor; the voltage division circuit is used for current limiting and voltage reduction, the first filter capacitor is used for isolating direct current generated in charging, discharging and motor reverse charging processes, the direct current is prevented from influencing the on-off state of the switching circuit, the technical problem that the on-off state of a door lock is easily misjudged in the prior art is solved, and the stability and reliability of the circuit are improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of circuits, and in particular relates to a washing machine control circuit and a washing machine. Background Art

[0002] Nowadays, household appliances such as washing machines, refrigerators, water heaters, etc. all use door lock detection circuits to detect whether the appliance is closed. Only when the door lock is closed normally can the appliance operate normally, preventing safety electricity problems caused by users forgetting to close the door lock.

[0003] At present, the logic of the door lock detection circuit used is simple. Its basic principle is that if the door lock is closed, the door lock detection circuit will collect the current after the door lock is turned on, and then send the collected signal to the MCU through the transistor for judgment, and the whole machine will operate normally. For ordinary rectifier circuits, this solution has clear logic and faces relatively simple interference signals.

[0004] For washing machines that use a voltage-doubler rectifier inverter board, the door lock will jitter during operation, generating interference signals. In addition, the voltage-doubler rectifier circuit will have three conditions: normal charging, motor reverse charging, and electrode discharge. This causes the interference signal to be variable and difficult to quantify. A large amount of calculations and experiments are required to test the parameters, which can easily lead to misjudgment of the door lock switch status. Summary of the invention

[0005] The utility model provides a washing machine control circuit, which solves the technical problem of easily misjudging the door lock switch state in the prior art.

[0006] In order to achieve the above technical objectives, the utility model adopts the following technical solutions:

[0007] A washing machine control circuit, comprising:

[0008] A power input interface, which includes a live wire terminal and a neutral wire terminal;

[0009] Main control unit;

[0010] Door lock switch;

[0011] a rectifier circuit, wherein a first input end of the rectifier circuit is connected to one end of the door lock switch, the other end of the door lock switch is connected to the live terminal, and a second input end of the rectifier circuit is connected to the neutral terminal; a first output end of the rectifier circuit is connected to the positive electrode of the first charging capacitor, a negative electrode of the first charging capacitor is connected to the positive electrode of the second charging capacitor, and a negative electrode of the second charging capacitor is connected to the second output end of the rectifier circuit; a connection node between the first charging capacitor and the second charging capacitor is connected to the first input end of the rectifier circuit;

[0012] A door lock detection circuit comprises a voltage divider circuit, a first filter capacitor, and a switch circuit; one end of the door lock switch is grounded through the voltage divider circuit, a voltage divider node of the voltage divider circuit is connected to one end of the first filter capacitor, the other end of the first filter capacitor is connected to the control end of the switch circuit, and the switch path of the switch circuit is connected to the main control unit.

[0013] In some embodiments of the present application, one end of the switch path of the switch circuit is connected to a DC power supply through a pull-up resistor, one end of the switch path of the switch circuit is connected to the main control unit, and the other end of the switch path of the switch circuit is grounded.

[0014] In some embodiments of the present application, the switch circuit includes an NPN transistor;

[0015] The base of the NPN transistor is connected to the other end of the first filter capacitor;

[0016] The emitter of the NPN transistor is grounded;

[0017] The collector of the NPN transistor is connected to the DC power supply through the pull-up resistor;

[0018] The collector of the NPN transistor is connected to the main control unit.

[0019] In some embodiments of the present application, the switch circuit includes an NMOS tube;

[0020] The gate of the NMOS tube is connected to the other end of the first filter capacitor;

[0021] The source of the NMOS tube is grounded;

[0022] The drain of the NMOS tube is connected to the DC power supply through the pull-up resistor;

[0023] The drain of the NMOS tube is connected to the main control unit.

[0024] In some embodiments of the present application, one end of the switch path of the switch circuit is connected to a DC power supply, the other end of the switch path of the switch circuit is grounded through a pull-down resistor, and the other end of the switch path of the first switch circuit is connected to the main control unit.

[0025] In some embodiments of the present application, the voltage-dividing circuit includes a first voltage-dividing resistor, a second voltage-dividing resistor, and a third voltage-dividing resistor;

[0026] One end of the first voltage-dividing resistor is connected to one end of the door lock switch, the other end of the first voltage-dividing resistor is connected to one end of the second voltage-dividing resistor, the other end of the second voltage-dividing resistor is connected to one end of the third voltage-dividing resistor, and the other end of the third voltage-dividing resistor is grounded;

[0027] A connection node between the second voltage-dividing resistor and the third voltage-dividing resistor is connected to one end of the first filter capacitor.

[0028] In some embodiments of the present application, a connection node between the second voltage-dividing resistor and the third voltage-dividing resistor is connected to one end of the first filter capacitor via a first current-limiting resistor.

[0029] In some embodiments of the present application, one end of the switch path of the switch circuit is connected to one end of a second current limiting resistor, and the other end of the second current limiting resistor is connected to the main control unit.

[0030] In some embodiments of the present application, the other end of the second current limiting resistor is grounded through a second filter capacitor.

[0031] Based on the design of the above washing machine control circuit, the utility model also proposes a washing machine, including the above washing machine control circuit.

[0032] Compared with the prior art, the advantages and positive effects of the utility model are as follows: the washing machine control circuit and washing machine of the utility model use a rectifier circuit to charge the first charging capacitor E1 and the second charging capacitor E2, and the connection node of the first charging capacitor E1 and the second charging capacitor E2 is connected to the first input end of the rectifier circuit to form a voltage doubling rectifier circuit; the voltage divider circuit is used to limit the current and reduce the voltage, and the first filter capacitor C2 is used to isolate the direct current generated during the charging, discharging, and motor reverse charging process, so as to avoid the generated direct current affecting the switching state of the switch circuit, thereby avoiding affecting the high and low signals output to the main control unit, and further avoiding the main control unit from misjudging the switching state of the door lock switch. Therefore, the washing machine control circuit of the utility model eliminates the influence of the direct current generated during charging, discharging, and motor reverse charging on the on-off state of the switch circuit, avoids the main control unit from misjudging the state of the door lock switch, solves the technical problem of the prior art that the door lock switch state is easily misjudged, and improves the stability and reliability of the circuit.

[0033] After reading the detailed description of the embodiments of the present invention in conjunction with the accompanying drawings, other features and advantages of the present invention will become more clear. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0035] Figure 1It is a circuit principle diagram of an embodiment of the washing machine control circuit proposed by the utility model;

[0036] Figure 2 This is the waveform diagram of the door lock signal and interference signal during the charging process;

[0037] Figure 3 This is the waveform diagram of the door lock signal and interference signal during the discharge process;

[0038] Figure 4 This is the waveform of the door lock signal and interference signal during the motor reverse charging process;

[0039] Figure 5 This is the signal waveform remaining after the DC signal is filtered by the capacitor. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

[0041] It should be noted that in the description of the present invention, the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0042] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" 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 those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0043] Embodiment 1

[0044] The washing machine control circuit of this embodiment includes a power input interface, a main control unit, a door lock switch SW1, a rectifier circuit, a door lock detection circuit, etc. Figure 1 shown.

[0045] The power input interface includes a live wire terminal and a neutral wire terminal. The power input interface is connected to the AC power, that is, the neutral wire terminal is connected to the neutral wire, and the live wire terminal is connected to the live wire.

[0046] When the washing machine door cover is closed, the door lock switch SW1 is closed. When the washing machine door cover is opened, the door lock switch SW1 is opened.

[0047] A rectifier circuit, wherein a first input end is connected to one end of the door lock switch SW1, the other end of the door lock switch SW1 is connected to the live wire terminal, and a second input end of the rectifier circuit is connected to the neutral wire terminal; a first output end of the rectifier circuit is connected to the positive electrode of the first charging capacitor E1, a negative electrode of the first charging capacitor E1 is connected to the positive electrode of the second charging capacitor E2, and a negative electrode of the second charging capacitor E2 is connected to the second output end of the rectifier circuit; a connection node between the first charging capacitor E1 and the second charging capacitor E2 is connected to the first input end of the rectifier circuit. The rectifier circuit rectifies the input AC power into DC power, and charges the first charging capacitor E1 and the second charging capacitor E2. The first charging capacitor E1 and the second charging capacitor E2 are used to power the motor.

[0048] In this embodiment, the first charging capacitor E1 and the second charging capacitor E2 are both electrolytic capacitors, which can be charged and discharged. In this embodiment, the rectifier circuit is a rectifier bridge BD1. A capacitor CX1 is connected between one end of the door lock switch SW1 and the neutral terminal.

[0049] The door lock detection circuit includes a voltage divider circuit, a first filter capacitor C2, and a switch circuit; one end of the door lock switch SW1 is grounded through the voltage divider circuit, the voltage divider node of the voltage divider circuit is connected to one end of the first filter capacitor C2, the other end of the first filter capacitor C2 is connected to the control end of the switch circuit, and the switch path of the switch circuit is connected to the main control unit. When the switch circuit is turned off or on, the signal sent to the main control unit is of different levels. The main control unit determines whether the door lock switch SW1 is closed based on the received signal, and when it is determined that the door lock switch SW1 is closed, the control motor starts to run.

[0050] When the door cover of the washing machine is closed, the door lock switch SW1 is closed, and the live wire current passes through the door lock switch SW1, part of which flows to the rectifier circuit and the other part flows to the door lock detection circuit. The signal flowing to the door lock detection circuit is recorded as the door lock signal L', see Figure 1 shown.

[0051] The rectifier circuit rectifies the input AC power and outputs DC power, which is used to charge the second charging capacitor E2 and the first charging capacitor E1 in turn. If the live and neutral terminals are connected to the mains, i.e., 220V AC power, the 220V AC power is rectified by the rectifier circuit and first charges the second charging capacitor E2. The voltage at the connection node of the two charging capacitors, i.e., the voltage at point a, will be around 155V. Then, the first charging capacitor E1 is charged, and the voltage at the positive electrode of the first charging capacitor E1, i.e., the VBus voltage, is maintained at around 310V.

[0052] The alternating current flowing to the door lock detection circuit is first divided by the voltage divider circuit, and then filtered out by the first filter capacitor C2 to remove the DC interference signal, and then flows to the control end of the switch circuit to control the on and off of the switch circuit. The switch path of the switch circuit transmits the signal to the main control unit, and the main control unit can determine whether the door lock switch SW1 is closed based on the received signal.

[0053] For example, when the door lock switch SW1 is disconnected, the switch circuit is turned off and the main control unit receives a high level; when the door lock switch SW1 is closed, the switch circuit is turned on and the main control unit receives a low level; the main control unit can determine whether the door lock switch SW1 is closed based on the received high and low levels.

[0054] During the operation of the washing machine, the door lock will vibrate, generating interference signals, which will enter the door lock detection circuit. Figure 2 As shown, the dotted line is the interference signal, and the solid line is the collected door lock signal L'.

[0055] During the discharge process, E1 and E2 are discharged in sequence. The waveform of the discharge process is as follows: Figure 3 As shown, Figure 3 The discharge process is essentially a process of Figure 2 Towards Figure 3 The dotted line is the interference signal, and the solid line is the collected door lock signal L'. In this process, the potential of L' will continue to decrease, the potential of the interference signal will also continue to decrease, and the potential at point a will continue to move down from 155V to 0V.

[0056] Motor reverse charging is a normal phenomenon when the motor is running. When the washing machine starts working, VBus will supply power to the motor through IPM, and the motor will work normally. If the motor stops working due to external influences, such as when the user pauses the washing machine, the motor will stop suddenly. This process will generate back electromotive force, and the voltage generated will be greater than the VBus voltage, which will cause the voltage to flow back to VBus through IPM, thereby affecting the voltage value of L'. For example, if the voltage generated by the emergency stop of the motor is stabilized at 400V, the potential of the VBus point will be raised from 310V to 400V, and the potential of point a will be raised from 155V to 200V. At the same time, the voltage of the interference signal will also be raised, such as Figure 4 As shown, the dotted line is the interference signal, and the solid line is the collected door lock signal L'.

[0057] During the charging process, discharging process, and motor reverse charging process, the interference generated by the door lock is unstable and difficult to quantify. By adding the first filter capacitor C2 in front of the control end of the switch circuit, the DC power is filtered out and the three states of the voltage doubler rectifier circuit are differentiated. The DC power generated during discharge and motor reverse charging will be directly filtered out and will not affect the door lock detection circuit. Only the AC power L needs to be considered, which reduces unnecessary interference and greatly reduces the difficulty of judgment, making the parameters of the door lock detection circuit more accurate and avoiding misjudgment by the main control unit.

[0058] The live terminal is connected to AC power L, and the potential of the collected door lock signal L' will change continuously in the three states of charging, discharging, and motor reverse charging. The power rectified by the rectifier circuit is DC power, so the potential raised by discharging and motor reverse charging is DC power. At the same time, during the charging process, the potential raised by the second charging capacitor E2 is also DC power.

[0059] The first filter capacitor C2 is designed before the control end of the switch circuit. The DC power generated by charging, discharging and reverse charging of the motor is filtered out by utilizing the characteristic of the capacitor "blocking DC and passing AC". This makes the current reaching the control end of the switch circuit only have AC power. The frequency of the AC power signal is basically consistent with the frequency of the AC power L at the live terminal, and is only reduced by equal times through the voltage divider resistor. Figure 5 shown.

[0060] Due to the characteristics of alternating current, the switch circuit will be periodically opened and closed, that is, the zero signal received by the main control unit is a periodic square wave. The main control unit can determine the switch state of the door lock switch based on the received signal, which is simple and convenient, avoids misjudgment, and greatly improves the anti-interference ability of the door lock detection circuit. At the same time, the calculation of the door lock detection circuit parameters is also simplified, reducing redundant interference and reducing the possibility of false triggering.

[0061] The washing machine control circuit of this embodiment uses a rectifier circuit to charge the first charging capacitor E1 and the second charging capacitor E2, and the connection node of the first charging capacitor E1 and the second charging capacitor E2 is connected to the first input end of the rectifier circuit to form a voltage doubling rectifier circuit; the voltage divider circuit is used to limit the current and reduce the voltage, and the first filter capacitor C2 is used to isolate the direct current generated during the charging, discharging, and motor reverse charging processes to prevent the generated direct current from affecting the switching state of the switch circuit, thereby avoiding affecting the high and low signals output to the main control unit, and further avoiding the main control unit from misjudging the switching state of the door lock switch. Therefore, the washing machine control circuit of this embodiment eliminates the influence of the direct current generated during charging, discharging, and motor reverse charging on the on-off state of the switch circuit, avoids the main control unit from misjudging the state of the door lock switch, solves the technical problem of easily misjudging the state of the door lock switch in the prior art, and improves the stability and reliability of the circuit.

[0062] The washing machine control circuit of this embodiment solves the problems that the potential changes continuously under the three conditions of charging, discharging and reverse charging of the motor, and the interference signals caused by the jitter of the door lock are various, making the parameters of the door lock detection circuit difficult to calculate, not accurate enough, and prone to false triggering.

[0063] The washing machine control circuit of this embodiment integrates the three situations of normal charging, electrolyte discharge, and motor reverse charging into the simplest one, which can make the selection of parameters of the door lock detection circuit more accurate, while reducing unnecessary interference and improving the circuit's anti-interference ability.

[0064] The washing machine control circuit of this embodiment uses the simplest circuit to implement door lock detection, while solving the interference problem in the voltage doubler rectifier circuit, improving the circuit's reliability, anti-interference ability, and anti-impact ability, while simplifying the work of the main control unit.

[0065] In some embodiments of the present application, one end of the switch path of the switch circuit is connected to a DC power supply (such as +5V) through a pull-up resistor R2, one end of the switch path of the switch circuit is connected to a main control unit, and the other end of the switch path of the switch circuit is grounded.

[0066] For example, when the door lock switch SW1 is turned off, the control end of the switch circuit is at a low level, the switch circuit is turned off, and one end of the switch path of the switch circuit is at a high level, so the main control unit receives a high level.

[0067] When the door lock switch SW1 is closed, the AC current is transmitted to the control end of the switch circuit through the door lock switch SW1, the voltage divider circuit, and the first filter capacitor C2. The control end of the switch circuit is at a high level, the switch circuit is turned on, one end of the switch path of the switch circuit is pulled to a low level, and the main control unit receives the low level.

[0068] That is, when the main control unit receives a high level, it determines that the door lock switch SW1 is disconnected; when the main control unit receives a low level, it determines that the door lock switch SW1 is closed.

[0069] By designing a pull-up resistor and a DC power supply, it is convenient for the main control unit to determine the switch state of the door lock switch; and the circuit structure is simple, easy to implement, and low in cost.

[0070] In some embodiments of the present application, the switch circuit includes a high on-state voltage drop switch tube, such as an NPN transistor or an NMOS tube.

[0071] In some embodiments of the present application, the switching circuit includes an NPN transistor N1; the base of the NPN transistor is connected to the other end of the first filter capacitor C2; the emitter of the NPN transistor is grounded; the collector of the NPN transistor is connected to a DC power supply through a pull-up resistor R2; the collector of the NPN transistor is connected to a main control unit and outputs a signal to the main control unit.

[0072] When the door lock switch SW1 is disconnected, the base of the NPN transistor is at a low level, the NPN transistor is turned off, and the collector of the NPN transistor is at a high level. Therefore, the main control unit receives a high level.

[0073] When the door lock switch SW1 is closed, the base of the NPN transistor is at a high level, the NPN transistor is turned on, and the collector of the NPN transistor is pulled down to a low level, so the main control unit receives a low level.

[0074] By selecting NPN transistors, the control is simple, the on and off control is convenient, the performance is stable and the cost is low.

[0075] In some embodiments of the present application, the switching circuit includes an NMOS tube; the gate of the NMOS tube is connected to the other end of the first filter capacitor; the source of the NMOS tube is grounded; the drain of the NMOS tube is connected to a DC power supply through a pull-up resistor; the drain of the NMOS tube is connected to the main control unit and outputs a signal to the main control unit.

[0076] When the door lock switch SW1 is turned off, the gate of the NMOS tube is at a low level, the NMOS tube is turned off, and the drain of the NMOS tube is at a high level. Therefore, the main control unit receives a high level.

[0077] When the door lock switch SW1 is closed, the gate of the NMOS tube is at a high level, the NMOS tube is turned on, and the drain of the NMOS tube is pulled down to a low level. Therefore, the main control unit receives a low level.

[0078] By selecting NMOS tubes, the control is simple, the on and off control is convenient, the performance is stable and the cost is low.

[0079] In some embodiments of the present application, in order to avoid excessive signals from impacting the main control unit and ensure the safety of the main control unit, one end of the switch path of the switch circuit is connected to one end of the second current limiting resistor R3, and the other end of the second current limiting resistor R3 is connected to the main control unit.

[0080] In some embodiments of the present application, the other end of the second current limiting resistor R3 is grounded through the second filter capacitor C1 to filter out noise and prevent the noise from being transmitted to the main control unit and affecting the determination of the main control unit.

[0081] In some other embodiments of the present application, one end of the switch path of the switch circuit is connected to a DC power supply, the other end of the switch path of the switch circuit is grounded through a pull-down resistor, and the other end of the switch path of the first switch circuit is connected to a main control unit.

[0082] For example, when the door lock switch SW1 is turned off, the control end of the switch circuit is at a low level, the switch circuit is turned off, and the other end of the switch path of the switch circuit is at a low level, so the main control unit receives a low level.

[0083] When the door lock switch SW1 is closed, the AC current is transmitted to the control end of the switch circuit through the door lock switch SW1, the voltage divider circuit, and the first filter capacitor C2. The control end of the switch circuit is at a high level, the switch circuit is turned on, and the other end of the switch path of the switch circuit is pulled to a high level, and the main control unit receives the high level.

[0084] That is, when the main control unit receives a low level, it determines that the door lock switch SW1 is disconnected; when the main control unit receives a high level, it determines that the door lock switch SW1 is closed.

[0085] By designing a pull-down resistor, it is convenient for the main control unit to determine the switch state of the door lock switch. The circuit structure is simple, easy to implement and low in cost.

[0086] In some embodiments of the present application, the voltage-dividing circuit includes a first voltage-dividing resistor R1 , a second voltage-dividing resistor R4 , and a third voltage-dividing resistor R6 .

[0087] One end of the first voltage-dividing resistor R1 is connected to one end of the door lock switch SW1, the other end of the first voltage-dividing resistor R1 is connected to one end of the second voltage-dividing resistor R4, the other end of the second voltage-dividing resistor R4 is connected to one end of the third voltage-dividing resistor R6, and the other end of the third voltage-dividing resistor R6 is grounded. The connection node between the second voltage-dividing resistor R4 and the third voltage-dividing resistor R6 is connected to one end of the first filter capacitor C2.

[0088] By designing the above-mentioned voltage divider circuit, the function of voltage division and current limiting is achieved, thereby preventing a large current from impacting the switch circuit; and the circuit structure is simple, easy to build, and low in cost.

[0089] In some embodiments of the present application, in order to further improve circuit safety and avoid excessive current, the connection node between the second voltage-dividing resistor R4 and the third voltage-dividing resistor R6 is connected to one end of the first filter capacitor C2 through the first current-limiting resistor R5.

[0090] Embodiment 2

[0091] Based on the design of the washing machine control circuit of the first embodiment, the second embodiment further proposes a washing machine, including the washing machine control circuit of the first embodiment.

[0092] By designing a washing machine control circuit in the washing machine, the influence of the direct current generated during charging and discharging and reverse charging of the motor on the switching state of the switching circuit is eliminated, and misjudgment of the state of the door lock switch is avoided. The technical problem of easy misjudgment of the state of the door lock switch in the prior art is solved. It is stable and reliable, and the performance and user experience of the washing machine are improved.

[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model 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 deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the utility model.

Claims

1. A washing machine control circuit, characterized in that: include: A power input interface, which includes a live wire terminal and a neutral wire terminal; Main control unit; Door lock switch; A rectifier circuit, wherein a first input end is connected to one end of the door lock switch, the other end of the door lock switch is connected to the live wire terminal, and a second input end of the rectifier circuit is connected to the neutral wire terminal; a first output end of the rectifier circuit is connected to the positive electrode of a first charging capacitor, a negative electrode of the first charging capacitor is connected to the positive electrode of a second charging capacitor, and a negative electrode of the second charging capacitor is connected to the second output end of the rectifier circuit; a connection node between the first charging capacitor and the second charging capacitor is connected to the first input end of the rectifier circuit; A door lock detection circuit comprises a voltage divider circuit, a first filter capacitor, and a switch circuit; one end of the door lock switch is grounded through the voltage divider circuit, a voltage divider node of the voltage divider circuit is connected to one end of the first filter capacitor, the other end of the first filter capacitor is connected to the control end of the switch circuit, and the switch path of the switch circuit is connected to the main control unit.

2. The washing machine control circuit according to claim 1, characterized in that: One end of the switch path of the switch circuit is connected to a DC power supply through a pull-up resistor, one end of the switch path of the switch circuit is connected to the main control unit, and the other end of the switch path of the switch circuit is grounded.

3. The washing machine control circuit according to claim 2, characterized in that: The switch circuit includes an NPN transistor; The base of the NPN transistor is connected to the other end of the first filter capacitor; The emitter of the NPN transistor is grounded; The collector of the NPN transistor is connected to the DC power supply through the pull-up resistor; The collector of the NPN transistor is connected to the main control unit.

4. The washing machine control circuit according to claim 2, characterized in that: The switch circuit includes an NMOS tube; The gate of the NMOS tube is connected to the other end of the first filter capacitor; The source of the NMOS tube is grounded; The drain of the NMOS tube is connected to the DC power supply through the pull-up resistor; The drain of the NMOS tube is connected to the main control unit.

5. The washing machine control circuit according to claim 1, characterized in that: One end of the switch path of the switch circuit is connected to a DC power supply, the other end of the switch path of the switch circuit is grounded via a pull-down resistor, and the other end of the switch path of the switch circuit is connected to the main control unit.

6. The washing machine control circuit according to claim 1, characterized in that: The voltage-dividing circuit comprises a first voltage-dividing resistor, a second voltage-dividing resistor, and a third voltage-dividing resistor; One end of the first voltage-dividing resistor is connected to one end of the door lock switch, the other end of the first voltage-dividing resistor is connected to one end of the second voltage-dividing resistor, the other end of the second voltage-dividing resistor is connected to one end of the third voltage-dividing resistor, and the other end of the third voltage-dividing resistor is grounded; A connection node between the second voltage-dividing resistor and the third voltage-dividing resistor is connected to one end of the first filter capacitor.

7. The washing machine control circuit according to claim 6, characterized in that: A connection node between the second voltage-dividing resistor and the third voltage-dividing resistor is connected to one end of the first filter capacitor via a first current-limiting resistor.

8. The washing machine control circuit according to claim 2, characterized in that: One end of the switch path of the switch circuit is connected to one end of a second current limiting resistor, and the other end of the second current limiting resistor is connected to the main control unit.

9. The washing machine control circuit according to claim 8, characterized in that: The other end of the second current limiting resistor is grounded through a second filter capacitor.

10. A washing machine, characterized in that: The washing machine control circuit comprises the washing machine control circuit as claimed in any one of claims 1 to 9.

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