DC water pump surge current absorption circuit and household electrical appliance

Abstract

The utility model relates to a direct-current water pump surge current absorption circuit and a household electrical appliance, and relates to the technical field of household electrical appliances. A zero line of an alternating-current power supply is connected with a first end of a first absorption resistor, and a live line is connected with a first end of a power switch; the first end of the water pump switch is connected with the second end of the power switch, the second end of the water pump switch is connected with the second input end of the rectifier, and the first end of the second absorption resistor is connected with the first end of the water pump switch; the first output end of the rectifier is connected with the positive electrode of the filter capacitor, and the second output end is connected with the negative electrode of the filter capacitor. The first output end of the rectifier is connected with the first end of the semiconductor switch, the second end of the semiconductor switch is connected with the first end of the water pump motor, and the second output end of the rectifier is connected with the second end of the water pump motor. The surge current generated when the direct-current water pump is started can be absorbed.

Description

Technical Field

[0001] The present application relates to the technical field of household appliances, and in particular to a DC water pump surge current absorption circuit and a household appliance. Background Art

[0002] At present, with the upgrading of wall-mounted boiler technology, DC water pumps are gradually being used. However, since DC water pumps have a complete rectifier and filter circuit inside and a large electrolytic capacitor after filtering, there will be a large surge current at the moment the water pump is powered on. If the surge current is not eliminated, it will easily damage the control device, leading to unpredictable consequences.

[0003] Therefore, there is an urgent need for a DC water pump surge current absorption circuit. Utility Model Content

[0004] Based on this, it is necessary to provide a DC water pump surge current absorption circuit and household appliances to address the above technical problems.

[0005] In a first aspect, a DC water pump surge current absorption circuit is provided, the circuit comprising an AC power supply, a power switch, a first absorption resistor, a water pump control circuit and a water pump motor; wherein:

[0006] The neutral line of the AC power supply is connected to the first end of the first absorption resistor, and the second end of the first absorption resistor is connected to the first input end of the water pump control circuit;

[0007] The live wire of the AC power supply is connected to the first end of the power switch, and the second end of the power switch is connected to the second input end of the water pump control circuit;

[0008] The first output end of the water pump control circuit is connected to the first end of the water pump motor;

[0009] The second output end of the water pump control circuit is connected to the second end of the water pump motor.

[0010] As an optional implementation, the first absorption resistor is a low-resistance, high-power resistor.

[0011] As an optional implementation, the resistance of the first absorption resistor is less than 10Ω and the power it can withstand is greater than 10W.

[0012] As an optional implementation, the water pump control circuit includes a water pump switch, a second absorption resistor, a rectifier, a filter capacitor, a semiconductor switch and a semiconductor switch control circuit; wherein,

[0013] The first input end of the rectifier is connected to the second end of the first absorption resistor;

[0014] The first end of the water pump switch is connected to the second end of the power switch, and the second end of the water pump switch is connected to the second input end of the rectifier;

[0015] The first end of the second absorption resistor is connected to the first end of the water pump switch, and the second end of the second absorption resistor is connected to the second end of the water pump switch;

[0016] The first output end of the rectifier is connected to the positive electrode of the filter capacitor, and the second output end is connected to the negative electrode of the filter capacitor;

[0017] The first output end of the rectifier is connected to the first end of the semiconductor switch, the second end of the semiconductor switch is connected to the first end of the water pump motor, and the third end of the semiconductor switch is connected to the semiconductor switch control circuit;

[0018] The second output end of the rectifier is connected to the second end of the water pump motor.

[0019] As an optional implementation, the semiconductor switch is a PNP transistor; wherein,

[0020] The first output end of the rectifier is connected to the emitter of the semiconductor switch, the collector of the semiconductor switch is connected to the first end of the water pump motor, and the base of the semiconductor switch is connected to the semiconductor switch control circuit.

[0021] As an optional implementation, the rectifier is a bridge rectifier.

[0022] As an optional implementation, the power switch and the water pump switch are relays.

[0023] As an optional implementation, the second absorption resistor is a PTC thermistor or an NTC thermistor.

[0024] As an optional implementation manner, the resistance of the second absorption resistor is greater than or equal to 200Ω.

[0025] In a second aspect, a household appliance is provided, comprising the DC water pump surge current absorption circuit as described in any one of the first aspects.

[0026] The present application provides a DC water pump surge current absorption circuit and household appliances. The technical solution provided by the embodiments of the present application brings at least the following beneficial effects: the circuit includes an AC power supply, a power switch, a first absorption resistor, a water pump control circuit and a water pump motor, and the water pump control circuit includes a water pump switch, a second absorption resistor, a rectifier, a filter capacitor, a semiconductor switch and a semiconductor switch control circuit; wherein, the neutral line of the AC power supply is connected to the first end of the first absorption resistor; the live line of the AC power supply is connected to the first end of the power switch, the first input end of the rectifier is connected to the second end of the first absorption resistor; the first end of the water pump switch is connected to the The second end of the power switch and the second end of the water pump switch are connected to the second input end of the rectifier; the first end of the second absorption resistor is connected to the first end of the water pump switch, and the second end of the second absorption resistor is connected to the second end of the water pump switch; the first output end of the rectifier is connected to the positive electrode of the filter capacitor, and the second output end is connected to the negative electrode of the filter capacitor; the first output end of the rectifier is connected to the first end of the semiconductor switch, the second end of the semiconductor switch is connected to the first end of the water pump motor, and the third end of the semiconductor switch is connected to the semiconductor switch control circuit; the second output end of the rectifier is connected to the second end of the water pump motor. With the circuit structure of the present application, the first absorption resistor absorbs the surge current generated by the water pump motor control circuit at startup, and the second absorption resistor is added before the internal rectification of the water pump. The surge current will be reduced to the current range that the water pump switch can withstand, which can solve the risk of damage to electrical components. At the same time, since the first absorption resistor is a low-resistance resistor, it will not affect the performance of the DC water pump.

[0027] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] 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 only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 A schematic diagram of the structure of a DC water pump surge current absorption circuit provided in an embodiment of the present application;

[0030] Figure 2 A schematic diagram of the structure of another DC water pump surge current absorption circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0032] The following will describe in detail a DC water pump surge current absorption circuit provided by an embodiment of the present application in conjunction with a specific implementation method. Figure 1 A schematic diagram of a DC water pump surge current absorption circuit provided in an embodiment of the present application is shown in FIG. Figure 1 As shown, the details are as follows:

[0033] The DC water pump surge current absorption circuit of the embodiment of the present application includes an AC power supply AC220V, a power switch K1, a first absorption resistor R1, a water pump control circuit 110 and a water pump motor M.

[0034] The neutral line N of the AC power source AC220V is connected to the first end of the first absorption resistor R1, and the second end of the first absorption resistor R1 is connected to the first input end of the water pump control circuit 110. Furthermore, the live line L of the AC power source AC220V is connected to the first end of the power switch K1, and the second end of the power switch K1 is connected to the second input end of the water pump control circuit 110.

[0035] It can be seen that the first absorption resistor R1 is connected to the front end of the water pump control circuit 110. The first absorption resistor is used as a first-level surge current absorption device at the output end of the AC power supply AC220V to protect the circuit.

[0036] The first output end of the water pump control circuit 110 is connected to the first end of the water pump motor M, and the second output end of the water pump control circuit 110 is connected to the second end of the water pump motor M.

[0037] In practice, surge current generally refers to the instantaneous incremental current of the power supply when a machine or device is just powered on. For example, at the moment when the power button of a household appliance is pressed, the household appliance can operate normally, but after pressing the power button, the electronic circuit inside the household appliance has not yet started working, which is equivalent to no-load. At this time, the resistance is very low. The power is suddenly turned on, so a large amount of surge current flows into the electrical equipment. After a period of time, the household appliance works normally, the surge current at this time disappears, and the power supply stably supplies the household appliance to operate. The DC water pump surge current absorption circuit of the embodiment of the present application solves the problem of large surge current when the water pump control circuit is started. In the present application, the neutral line N of the AC power supply AC220V is connected to the first end of the first absorption resistor R1, and the second end of the first absorption resistor R1 is connected to the first input end of the water pump control circuit 110. Furthermore, the live wire L of the AC power supply AC220V is connected to the first end of the power switch K1, and the second end of the power switch K1 is connected to the second input end of the water pump control circuit 110; the first output end of the water pump control circuit 110 is connected to the first end of the water pump motor M, and the second output end of the water pump control circuit 110 is connected to the second end of the water pump motor M, which is used to control the working state of the water pump motor.

[0038] Preferably, in order to protect the water pump control circuit 110, a protection circuit may be provided at the front end of the first absorption resistor R1, and the protection circuit may include a third absorption resistor and a fuse. By connecting the DC water pump surge current absorption circuit and the protection circuit, the damage of the surge current to the water pump control circuit can be effectively reduced, and the damage caused by the surge current when the water pump is started and stopped can be avoided, so that the water pump can operate safely for a longer period of time.

[0039] Furthermore, the first absorption resistor R1 can be a low-resistance high-power resistor. This can not only absorb the surge current, but also protect the water pump control circuit. Generally, the resistance of the first absorption resistor R1 is less than 10Ω, so that the surge current flows through the first absorption resistor R1, which can effectively protect the water pump control circuit from being damaged by the surge current. The "high-power resistor" mentioned here can be understood as a resistor with a power of more than 10W, which meets the instantaneous current when the water pump motor of the water pump system starts.

[0040] Optionally, in order to prevent the first absorption resistor R1 from being burned out due to excessive current when the surge current passes through it, the resistance of the first absorption resistor R1 may be greater than or equal to 100Ω. In this case, the first absorption resistor has a buffering effect, can absorb the surge current, and ensure the normal operation of the water pump control circuit.

[0041] Figure 2 A schematic diagram of another DC water pump surge current absorption circuit provided in an embodiment of the present application is shown in FIG. Figure 2As shown, the DC water pump surge current absorption circuit 110 of the embodiment of the present application includes a second absorption resistor R2, a rectifier DB1, a filter capacitor EC1, a semiconductor switch Q1, a semiconductor switch control circuit 1101, and a water pump switch K2. One end of the water pump switch K2 is connected to the input end of the rectifier DB1, and the other end is connected to the AC power supply AC220V through the first absorption resistor R1. A second absorption resistor R2 (such as a PTC or NTC thermistor (not less than 200Ω) is set in front of the rectifier DB1 as a second-level surge current absorption device to further absorb the surge current. The output end of the rectifier DB1 is connected to the filter capacitor EC1 and the semiconductor switch Q1, and the filter capacitor EC1 can smooth the filter output. The third end (control end) of the semiconductor switch Q1 is connected to the semiconductor switch control circuit 1101, which is used to control the on and off of the semiconductor switch Q1. If the second absorption resistor R2 fails, the instantaneous surge current (up to 80A) is much higher than the maximum instantaneous current that a general relay control device can withstand, thereby causing the water pump switch K2 to stick instantly. Therefore, the present application designs a two-stage surge current absorption scheme. After the second absorption resistor R2, the surge current will be reduced to the current range that a general relay can withstand after being absorbed by the first absorption resistor R1, which can greatly solve the risk of damage to the relay control device. At the same time, since the resistance value of the resistor is very small, it will not have much impact on the performance of the water pump itself.

[0042] Specifically, the water pump switch K2 of the embodiment of the present application can use a relay to convert the magnetic field signal generated by the stator part of the water pump motor into a control signal and send it to the semiconductor switch Q1 to drive the water pump switch K2 to operate the entire water pump.

[0043] It is understandable that the water pump control circuit generally includes a stator position detection circuit, a controller, and an inverter circuit, and the inverter circuit drives the water pump motor to operate through a semiconductor switch. Specifically, the semiconductor switch can be an NPN transistor, or preferably a PNP transistor, as long as it can drive the water pump motor to operate. When the input end receives a signal, the base of the PNP transistor is energized, and after the circuit is opened, the collector has an electric potential, so that the stator part generates a magnetic field to control the operation of the water pump.

[0044] Furthermore, the water pump control circuit also includes a stator position detection circuit, a controller and an inverter circuit.

[0045] The DC water pump surge current absorption circuit of the embodiment of the present application effectively absorbs the surge current of the entire circuit through the relay connected to the stator part detection of the water pump motor and the circuit for absorbing surge current at the front end. The DC water pump surge current absorption circuit of the embodiment of the present application can effectively reduce the damage of the surge current to the water pump control circuit, avoid the damage caused by the surge current when the water pump is started and stopped, and enable the water pump to operate safely for a longer period of time.

[0046] The embodiment of the present application provides a DC water pump surge current absorption circuit, the circuit includes an AC power supply, a power switch, a first absorption resistor, a water pump control circuit and a water pump motor, the water pump control circuit includes a water pump switch, a second absorption resistor, a rectifier, a filter capacitor, a semiconductor switch and a semiconductor switch control circuit; wherein, the neutral line of the AC power supply is connected to the first end of the first absorption resistor; the live line of the AC power supply is connected to the first end of the power switch, and the first input end of the rectifier is connected to the second end of the first absorption resistor; the first end of the water pump switch is connected to the second end of the power switch, and the second end of the water pump switch is connected to the second input end of the rectifier; the first end of the second absorption resistor is connected to the first end of the water pump switch, and the second end of the second absorption resistor is connected to the second end of the water pump switch; the first output end of the rectifier is connected to the positive electrode of the filter capacitor, and the second output end is connected to the negative electrode of the filter capacitor; the first output end of the rectifier is connected to the first end of the semiconductor switch, the second end of the semiconductor switch is connected to the first end of the water pump motor, and the third end of the semiconductor switch is connected to the semiconductor switch control circuit; the second output end of the rectifier is connected to the second end of the water pump motor. By adopting the circuit structure of the present application, the first absorption resistor absorbs the surge current generated by the water pump motor control circuit during startup, and the second absorption resistor is added before the internal rectification of the water pump. The surge current will be reduced to the current range that the water pump switch can withstand, which can solve the risk of damage to electrical components. At the same time, since the first absorption resistor is a low-resistance resistor, it will not affect the performance of the DC water pump.

[0047] It can be understood that the same / similar parts between the various embodiments of the above method in this specification can refer to each other, and each embodiment focuses on the differences from other embodiments. For related points, please refer to the description of other method embodiments.

[0048] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0049] It should also be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for display, data for analysis, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties.

[0050] Each embodiment in this specification is described in a related manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0051] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0052] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the utility model patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A DC water pump surge current absorption circuit, characterized in that: The circuit includes an AC power supply, a power switch, a first absorption resistor, a water pump control circuit and a water pump motor; wherein, The neutral line of the AC power supply is connected to the first end of the first absorption resistor, and the second end of the first absorption resistor is connected to the first input end of the water pump control circuit; The live wire of the AC power supply is connected to the first end of the power switch, and the second end of the power switch is connected to the second input end of the water pump control circuit; The first output end of the water pump control circuit is connected to the first end of the water pump motor; The second output end of the water pump control circuit is connected to the second end of the water pump motor.

2. The circuit according to claim 1, characterized in that The first absorption resistor is a low-resistance and high-power resistor.

3. The circuit according to claim 1, characterized in that The resistance of the first absorption resistor is less than 10Ω, and the power it can withstand is greater than 10W.

4. The circuit according to claim 1, characterized in that The water pump control circuit includes a water pump switch, a second absorption resistor, a rectifier, a filter capacitor, a semiconductor switch and a semiconductor switch control circuit; wherein, The first input end of the rectifier is connected to the second end of the first absorption resistor; The first end of the water pump switch is connected to the second end of the power switch, and the second end of the water pump switch is connected to the second input end of the rectifier; The first end of the second absorption resistor is connected to the first end of the water pump switch, and the second end of the second absorption resistor is connected to the second end of the water pump switch; The first output end of the rectifier is connected to the positive electrode of the filter capacitor, and the second output end is connected to the negative electrode of the filter capacitor; The first output end of the rectifier is connected to the first end of the semiconductor switch, the second end of the semiconductor switch is connected to the first end of the water pump motor, and the third end of the semiconductor switch is connected to the semiconductor switch control circuit; The second output end of the rectifier is connected to the second end of the water pump motor.

5. The circuit according to claim 4, characterized in that The semiconductor switch is a PNP type transistor; wherein, The first output end of the rectifier is connected to the emitter of the semiconductor switch, the collector of the semiconductor switch is connected to the first end of the water pump motor, and the base of the semiconductor switch is connected to the semiconductor switch control circuit.

6. The circuit according to claim 5, characterized in that The rectifier is a bridge rectifier.

7. The circuit according to claim 4, characterized in that The power switch and the water pump switch are relays.

8. The circuit according to claim 4, characterized in that The second absorption resistor is a PTC thermistor or an NTC thermistor.

9. The circuit according to claim 4, characterized in that The resistance of the second absorption resistor is greater than or equal to 200Ω.

10. A household appliance, characterized in that: The household appliance comprises a DC water pump surge current absorption circuit as described in any one of claims 1 to 9.

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