CN219697308U - Power supply circuit, variable frequency control circuit and refrigerator - Google Patents

Abstract

The utility model discloses a power supply circuit, a variable frequency control circuit and a refrigerator, which are applied to the technical field of power supply safety.

Description

Power supply circuit, variable frequency control circuit and refrigerator

Technical Field

The utility model relates to the technical field of power supply safety, in particular to a power supply circuit, a variable frequency control circuit and a refrigerator.

Background

With the rapid development of the automobile industry, the demand for on-board refrigerators in automobile parts is also being pulled. In recent years, the vehicle-mounted refrigerator mainly adopts a frequency conversion technology, and is more energy-saving and environment-friendly compared with a common household refrigerator. However, the working environment of the vehicle-mounted refrigerator is severe, and the vehicle-mounted refrigerator is often required to work in a jolt and shake state, so that the vehicle-mounted refrigerator is required to have high reliability so as to ensure normal operation in severe environments.

At present, the vehicle-mounted refrigerator is mainly powered by a power supply on an automobile, the power supply on the automobile is a direct current power supply, and the direct current power supply has positive and negative poles, so that when the power supply of the vehicle-mounted refrigerator is switched on, the situation that the power supply is reversely connected exists, the vehicle-mounted refrigerator is damaged, and potential safety hazards are caused.

Disclosure of Invention

The embodiment of the utility model provides a relay driving circuit, a refrigerator and household appliances, which can reduce the influence of impact current on consumption, material transfer quantity and the like of a relay during the action of the relay, so as to prolong the service life of the relay and improve the working reliability of the relay.

In order to solve the above-described problems, the present utility model provides, in a first aspect, a power supply circuit including:

the collector of the triode is connected with the first voltage end, the base of the triode is respectively connected with the first voltage end and the second voltage end, and the emitter of the triode is respectively connected with the third voltage end and the power utilization circuit;

the grid electrode of the field effect tube is connected with the first voltage end, the source electrode of the field effect tube is connected with the second voltage end, and the drain electrode of the field effect tube is connected with the fourth voltage end.

Optionally, the power supply circuit further includes:

one end of the first resistor is connected with the collector electrode of the triode, and the other end of the first resistor is connected with the first voltage end;

one end of the second resistor is connected with one end of the first resistor, and the other end of the second resistor is connected with the base electrode of the third transistor;

the cathode of the first diode is connected with the other end of the second resistor, and the anode of the first diode is connected with the second voltage end;

one end of the first capacitor is connected with the base electrode of the triode, and the other end of the first capacitor is connected with the second voltage end;

one end of the second capacitor is connected with the emitter of the triode, and the other end of the second capacitor is connected with the second voltage end;

and one end of the third capacitor is connected with the emitter of the triode, and the other end of the third capacitor is connected with the second voltage end.

Optionally, the power supply circuit further includes:

one end of the third resistor is connected with the first voltage end, and the other end of the third resistor is connected with the grid electrode of the field effect tube;

one end of the fourth capacitor is connected with the first voltage end, and the other end of the fourth capacitor is connected with the source electrode of the field effect transistor;

and the cathode of the second diode is connected with the grid electrode of the field effect tube, and the anode of the second diode is connected with the source electrode of the field effect tube.

In order to solve the above-mentioned problems, a second aspect of the present utility model provides a frequency conversion control circuit, comprising:

the processor is used for receiving and processing the external signal, generating a control signal and transmitting the control signal;

the compressor driving circuit is connected with the processor and is used for receiving the control signal and driving the compressor according to the control signal;

any one of the power supply circuits of the first aspect, connected to the processor and the compressor driving circuit, respectively, for supplying power to the compressor driving circuit and the processor.

Optionally, the frequency conversion control circuit further includes:

and the compressor rotating speed signal input unit is connected with the processor and is used for inputting a compressor rotating speed control signal to the processor so that the processor controls the compressor driving unit according to the compressor rotating speed control signal.

Optionally, the compressor rotation speed signal input unit includes:

one end of the fourth resistor is used for receiving a compressor rotating speed control signal;

the first end of the first optocoupler is connected with the other end of the fourth resistor, the second end of the first optocoupler is connected with a fifth voltage end, and the fourth end of the first optocoupler is connected with a sixth voltage end;

the first end of the second optocoupler is connected with the fifth voltage end, the second end of the second optocoupler is connected with the other end of the fourth resistor, and the fourth end of the second optocoupler is connected with the sixth voltage end;

one end of the fifth resistor is connected with the processor, and the other end of the fifth resistor is respectively connected with the third end of the first optocoupler and the third end of the second optocoupler;

one end of the sixth resistor is connected with the third end of the first optocoupler, and the second end of the sixth resistor is connected with a seventh voltage end;

and one end of the fifth capacitor is connected with the other end of the fifth resistor, and the second end of the fifth capacitor is connected with the seventh voltage end.

Optionally, the frequency conversion control circuit further includes:

and the compressor identification signal input unit is connected with the processor and is used for inputting a compressor identification signal to the processor so that the processor can identify the compressor according to the compressor identification signal.

Optionally, the compressor identification signal input unit includes:

an eighth voltage terminal and a ninth voltage terminal, wherein the eighth voltage terminal is connected with the ninth voltage terminal to form a loop;

and the identification signal output end is arranged on the loop and used for outputting a compressor identification signal to the processor.

Optionally, the compressor identification input unit includes:

one end of the seventh resistor is connected with the processor, and the other end of the seventh resistor is connected with the four-terminal socket;

and one end of the eighth resistor is connected with the processor, and the other end of the eighth resistor is connected with the four-terminal socket.

In order to solve the above-mentioned problems, in a third aspect, the present utility model provides a refrigerator including any one of the frequency conversion control circuits of the second aspect.

According to the utility model, the collector electrode of the triode is connected with the first voltage end, the base electrode of the triode is respectively connected with the first voltage end and the second voltage end, the emitter electrode of the triode is respectively connected with the third voltage end and the power utilization circuit, the grid electrode of the field effect tube is connected with the first voltage end, the source electrode of the field effect tube is connected with the second voltage end, the drain electrode of the field effect tube is connected with the fourth voltage end, if the first voltage end and the second voltage end are in positive connection (i.e. power supply positive connection), the field effect tube is conducted, the output voltage of the emitter electrode of the triode can be limited based on the driving voltage of the triode, and the voltage output by the emitter electrode of the triode is used as the input voltage of the power utilization circuit, so that low-voltage power supply of the power utilization circuit can be realized, if the first voltage end and the second voltage end are in reverse connection (i.e. power supply negative connection), the field effect tube is cut off, namely the emitter electrode of the triode is not in low-voltage power supply of the power utilization circuit, so that damage of the power utilization circuit can be avoided, and safety and reliability in the use of the circuit can be improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings that are needed in the description of the embodiments of the present utility model will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present utility model, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of a power supply circuit according to an embodiment of the utility model;

FIG. 2 is a schematic diagram of a power supply circuit according to another embodiment of the present utility model;

FIG. 3 is a schematic diagram of a power supply circuit according to another embodiment of the present utility model;

FIG. 4 is a schematic diagram of a frequency conversion control circuit according to an embodiment of the present utility model;

FIG. 5 is a schematic diagram of a frequency conversion control circuit according to another embodiment of the present utility model;

FIG. 6 is a schematic diagram of a compressor speed signal input unit according to an embodiment of the present utility model;

FIG. 7 is a schematic diagram of a frequency conversion control circuit according to another embodiment of the present utility model;

FIG. 8 is a schematic diagram of a frequency conversion control circuit according to another embodiment of the present utility model;

FIG. 9 is a schematic diagram of a compressor identification signal input unit according to an embodiment of the utility model;

FIG. 10 is a schematic diagram of a compressor identification signal input unit according to another embodiment of the present utility model;

FIG. 11 is a schematic diagram of a compressor identification signal input unit according to another embodiment of the present utility model;

FIG. 12 is a schematic diagram of a compressor identification signal input unit according to another embodiment of the present utility model;

FIG. 13 is a schematic diagram showing a structure of a compressor identification signal input unit according to another embodiment of the present utility model; fig. 14 is a schematic view of a refrigerator in an embodiment of the present utility model.

Description of the main reference signs

First to twelfth resistors R1 to R12

First to fifth capacitances C1 to C5

First diode to second diode D1-D2

First to ninth voltage terminals U1 to U9

Triode N1

Field effect transistor N2

First to second photocouplers L1 to L2

Power supply circuit 10

Frequency conversion control circuit 20

Processor 201

Compressor drive circuit 202

Compressor rotational speed signal input unit 203

Compressor identification signal input unit 204

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments may be embodied in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art. The drawings are merely schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and thus a repetitive description thereof will be omitted.

Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the present disclosure. However, those skilled in the art will recognize that the aspects of the present disclosure may be practiced with one or more of the specific details, or with other methods, components, devices, steps, etc. In other instances, well-known structures, methods, devices, implementations, materials, or operations are not shown or described in detail to avoid obscuring aspects of the disclosure.

In the present disclosure, unless explicitly specified and limited otherwise, the terms "coupled," "connected," and the like are to be construed broadly, and may be fixedly attached, detachably attached, or integrally formed, for example; can be electrically connected or communicated with each other; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the terms in this disclosure will be understood by those of ordinary skill in the art as the case may be.

Furthermore, in the description of the present utility model, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise. "and/or" describes an association relationship of an associated object, meaning that there may be three relationships, e.g., a and/or B, and that there may be a alone, B alone, and both a and B. The symbol "/" generally indicates that the context-dependent object is an "or" relationship. The terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature.

In one embodiment, fig. 1 shows a schematic structure of a power supply circuit of the present utility model, and as shown in fig. 1, a power supply circuit 10 includes a field effect transistor N2 and a transistor N1.

The collector of the triode N1 is connected with the first voltage end U1, the base electrode of the triode N1 is respectively connected with the first voltage end U1 and the second voltage end U2, and the emitter of the triode N1 is respectively connected with the third voltage end U3 and the power utilization circuit; the grid electrode of the field effect tube N2 is connected with the first voltage end U1, the source electrode of the field effect tube N2 is connected with the second voltage end U2, and the drain electrode of the field effect tube N2 is connected with the fourth voltage end U4.

The first voltage terminal is a bus voltage terminal, which may be 12V to 24V, the second voltage terminal is grounded with respect to the first voltage terminal, the third voltage terminal may be 5V, and the fourth voltage terminal is grounded with respect to the emitter of the triode.

The power utilization circuit can be electric equipment such as a mobile phone, a notebook computer, a flashlight, a tablet personal computer, a digital camera, a radio and an electric mosquito swatter, and can also be a frequency conversion control circuit in a direct current refrigerator and the like, and is not particularly limited herein.

The driving voltage range of the triode is assumed to be more than 9.6V and less than 20V, the first voltage end provides 15V voltage, when the first voltage end and the second voltage end are in positive connection (namely, the power supply is in positive connection), the source electrode of the field effect tube is conducted with the drain electrode of the field effect tube, and under the power supply of the first voltage end, the triode is conducted, so that the emitter electrode of the triode generates voltage not more than 14.3V, and 14.3V voltage is provided for the power utilization circuit; when the first voltage end and the second voltage tube are reversely connected (namely, the power supply is reversely connected), the field effect tube is cut off, and the triode is also cut off at the moment, so that the damage to the power utilization circuit is prevented, the function of protecting the power utilization circuit is achieved, and the safety and reliability of the power utilization circuit are improved.

In this embodiment, the collector of the triode is connected to the first voltage end, the base of the triode is connected to the first voltage end and the second voltage end respectively, the emitter of the triode is connected to the third voltage end and the power utilization circuit respectively, the gate of the field effect tube is connected to the first voltage end, the source of the field effect tube is connected to the second voltage end, the drain of the field effect tube is connected to the fourth voltage end, if the first voltage end and the second voltage end are connected positively (i.e. the power supply is connected positively), the field effect tube is turned on, the output voltage of the emitter of the triode can be limited based on the driving voltage of the triode, and the voltage output by the emitter of the triode is used as the input voltage of the power utilization circuit, so that low-voltage power supply of the power utilization circuit can be realized.

In an embodiment, fig. 2 shows a schematic structural diagram of a further power supply circuit, and as shown in fig. 3, the power supply circuit 10 further includes a first resistor R1, a second resistor R2, a first diode D1, a first capacitor C1, a second capacitor C2, and a third capacitor C3.

One end of the first resistor R1 is connected with the collector of the transistor N1, and the other end of the first resistor R1 is connected with the first voltage end U1; one end of the second resistor R2 is connected with one end of the first resistor R1, and the other end of the second resistor R2 is connected with the base electrode of the transistor N1; the cathode of the first diode D1 is connected with the other end of the second resistor R2, and the anode of the first diode D1 is connected with the second voltage end U2; one end of the first capacitor C1 is connected with the base electrode of the triode N1, and the other end of the first capacitor C1 is connected with the second voltage end U2; one end of the second capacitor C2 is connected with the emitter of the triode N1, and the other end of the second capacitor C2 is connected with the second voltage end U2; one end of the third capacitor C3 is connected with the emitter of the triode N1, and the other end of the third capacitor C3 is connected with the second voltage end U2.

The first resistor and the second resistor may be current limiting resistors, and are used for preventing the triode from being damaged due to overlarge input current, so as to play a role in protecting the triode, the first diode may be a voltage stabilizing diode, and is used for clamping the voltage (such as 15V) of the base electrode of the triode, namely limiting the voltage of the base electrode of the triode, so that the voltage not greater than the limiting voltage is generated at the emitter electrode of the triode (such as limiting the voltage of the base electrode of the triode, and limiting the voltage to be 14.3V), the voltage is supplied to the power utilization circuit, the first capacitor can filter interference signals in the current signals of the base electrode of the input triode, and the second capacitor and the third capacitor are used for filtering interference signals in the emitter electrode of the triode.

Fig. 3 shows a schematic diagram of a further power supply circuit, and as shown in fig. 3, the power supply circuit 10 further includes a third resistor R3, a fourth capacitor C4, and a second diode D2.

One end of the third resistor R3 is connected with the first voltage end U1, and the other end of the third resistor R3 is connected with the grid electrode of the field effect transistor N2; one end of the fourth capacitor C4 is connected with the first voltage end U1, and the other end of the fourth capacitor C4 is connected with the source electrode of the field effect transistor N2; the cathode of the second diode D2 is connected with the grid electrode of the field effect transistor N2, and the anode of the second diode D2 is connected with the source electrode of the field effect transistor N2.

The third resistor may be a current limiting resistor, which can reduce the fluctuation amplitude of the oscillation generated by the field effect transistor in the switching process, improve the stability of the field effect transistor switch, the fourth capacitor may filter the interference signal in the signal input to the source electrode of the field effect transistor, the second diode may be a voltage stabilizing diode, which is used for clamping the voltage (e.g. 20V) between the grid electrode of the field effect transistor and the source electrode of the field effect transistor, i.e. limiting the voltage between the grid electrode of the field effect transistor and the source electrode of the field effect transistor, and improve the stability of the field effect transistor during operation.

Fig. 4 shows a schematic diagram of a frequency conversion control circuit, and as shown in fig. 4, the frequency conversion control circuit 20 includes a processor 201, a compressor driving circuit 202, and any of the power supply circuits 10 in the above embodiments.

The processor 201 is configured to receive an external signal, process the external signal, generate a control signal, and send the control signal, where the external signal may be a compressor rotation speed control signal, a compressor identification signal, etc., the external signal is determined according to an actual application scenario, and is not specifically limited herein, and according to the actual application scenario, the processor 201 may use the external signal as the control signal, or may generate the control signal according to the external signal; the compressor driving circuit 202 is connected to the processor 201, and is configured to receive a control signal and drive a compressor (not shown) according to the control signal; any of the above embodiments of the power supply circuit 10 is connected to the processor 201 and the compressor driving circuit 201, respectively, for supplying power to the compressor driving circuit 201 and the processor 201. Through the connection, the power supply circuit 10 can not supply power to the processor 201 and the compressor 202 under the condition of reverse power supply connection, so that the processor 201 and the compressor drive circuit 202 are prevented from being damaged due to reverse power supply connection when the processor 201 and the compressor drive circuit 202 are used, the safety and the reliability of the processor 201 and the compressor drive circuit 202 in use are improved, and the safety and the reliability of the frequency conversion control circuit 20 are improved.

Fig. 5 shows a schematic structural diagram of a further inverter control circuit, and as shown in fig. 6, the inverter control circuit 20 further includes a compressor rotation speed signal input unit 203.

The compressor rotation speed signal input unit 203 is connected to the processor 201, and is configured to input a compressor rotation speed control signal to the processor 201, so that the processor 201 controls the compressor driving circuit 202 according to the compressor rotation speed control signal.

Fig. 6 shows a schematic structural diagram of a compressor rotation speed signal input unit, and as shown in fig. 6, the compressor rotation speed signal input unit 203 includes a fourth resistor R4, a first optocoupler L1, a second optocoupler L2, a fifth resistor R5, a sixth resistor R5, and a fifth capacitor C5.

One end of the fourth resistor R4 is used for receiving a compressor rotation speed control signal; the first end of the first optocoupler L1 is connected with the other end of the fourth resistor R4, the second end of the first optocoupler L1 is connected with the fifth voltage end U5, and the fourth end of the first optocoupler L1 is connected with the sixth voltage end U6; the first end of the second optocoupler L2 is connected with a fifth voltage end U5, the second end of the second optocoupler L2 is connected with the other end of the fourth resistor R4, and the fourth end of the second optocoupler L2 is connected with a sixth voltage end U6; one end of the fifth resistor R5 is connected with the processor 201, and the other end of the fifth resistor R5 is respectively connected with the third end of the first optocoupler L1 and the third end of the second optocoupler L2; one end of the sixth resistor R6 is connected with the third end of the first optocoupler L1, and the second end of the sixth resistor R6 is connected with the seventh voltage end U7; one end of the fifth capacitor C5 is connected to the other end of the fifth resistor R5, and the second end of the fifth capacitor C5 is connected to the seventh voltage end U7.

The fifth voltage terminal is a grounded terminal with respect to an emitter of the triode, the sixth voltage terminal may be 5V, and the seventh voltage terminal is a grounded terminal with respect to the bus voltage terminal.

The compressor rotation speed control signal may be a switching signal (for example, 0 represents an off signal and 1 represents an on signal), or may be a pulse modulation signal, which may be determined according to an actual application scenario, and is not specifically limited herein.

The fourth resistor may be a current limiting resistor, and is configured to limit an input current of the first end of the first optocoupler and the second end of the second tube optocoupler, prevent the first optocoupler and the second optocoupler from being damaged due to an excessive input current, and protect the first optocoupler and the second optocoupler;

the fifth resistor can be a current limiting resistor and is used for limiting the input current of the processor, preventing the processor from being damaged due to overlarge input current and protecting the processor;

the sixth resistor and the fifth capacitor are connected in parallel to form a filter circuit, so that interference signals in the compressor rotation speed control signals output by the third end of the first optical coupler and the third end of the second optical coupler can be filtered, and the stability and reliability of output signals are improved;

when the direction of the compressor rotation speed control signal is positive (such as a 0+1+0+1+0+1 pulse modulation signal or a +1 on signal), the first optocoupler is turned on, the second optocoupler is turned off, and the compressor rotation speed control signal is output through a third end of the first optocoupler; when the direction of the compressor rotation speed control signal is negative (such as a pulse modulation signal of 0-1 0-1 0-1 0-1 or an on signal of-1), the first optocoupler is turned off, the second optocoupler is turned on, and the compressor rotation speed control signal is output through the third end of the second optocoupler.

In this embodiment, whether the compressor rotation speed control signal received by one end of the fourth resistor is a negative signal or a positive signal (i.e., the direction of the compressor rotation speed signal is opposite), normal input of the compressor rotation speed control signal can be achieved, so that the processor receives the compressor rotation speed control signal, thereby improving reliability of the frequency conversion control circuit.

Fig. 7 shows a schematic structural diagram of a further inverter control circuit, and as shown in fig. 7, the inverter control circuit 20 further includes a compressor identification signal input unit 204.

The compressor identification signal input unit 204 is connected to the processor 201, and is configured to input a compressor identification signal to the processor 201, so that the processor 201 identifies the compressor according to the compressor identification signal.

Optionally, fig. 8 shows a schematic structural diagram of a further frequency conversion control circuit, as shown in fig. 8, where the frequency conversion control circuit further includes a filtering and LDO (low dropout regulator, low dropout linear regulator) unit, connected to the power supply circuit 10, the processor 201, and the compressor driving circuit 202, respectively, for adjusting an output voltage of the power supply circuit 10 to supply the power supply voltage 202 to the processor 201 and the compressor driving circuit;

a fan unit connected to the processor 201 for radiating heat from the frequency conversion control circuit 20;

a protection unit, respectively connected to the processor 201 and the compressor driving circuit 202, for improving protection such as overvoltage and overcurrent for the compressor driving circuit 202;

a compressor interface, coupled to the compressor drive circuit 202, for coupling to a compressor.

Fig. 9 shows a schematic structural diagram of a compressor identification signal input unit, and as shown in fig. 9, the compressor identification signal input unit 204 includes an eighth voltage terminal U8, a ninth voltage terminal U9, and an identification signal output terminal.

The eighth voltage end U8 is connected with the ninth voltage end U9 to form a loop; the identification signal output is provided on the circuit for outputting the compressor identification signal to the processor 201.

The compressor identification signal may be a high level signal (e.g., 1), a low level signal (e.g., 0), or a combination of high level signals and/or low level signals (e.g., 00, 01, 10), which is not specifically limited herein. It should be noted that the high level signal and the ground level signal are relatively, for example, a high level signal is 5V, and a low level signal is less than 5V (e.g., 4V).

Specifically, the compressor identification signal output from the identification signal output terminal may be determined by the voltages of the eighth voltage terminal and the ninth voltage terminal.

In this embodiment, the processor can accurately identify the compressor by acquiring the compressor identification signal output by the identification signal output end, which is beneficial to the processor to accurately control the compressor driving circuit and improve the reliability of the variable frequency control circuit.

Optionally, fig. 10 shows a schematic structural diagram of a further compressor identification signal input unit, and as shown in the drawing, the compressor identification signal input unit 204 further includes a ninth resistor R9 and a tenth resistor R10, that is, the ninth resistor R9 and/or the tenth resistor R10 are connected in series on the circuit.

Specifically, one end of the ninth resistor R9 is connected to the eighth voltage terminal U8, and the other end of the ninth resistor R9 is connected to the identification signal output terminal and the ninth voltage terminal U9, respectively.

The compressor identification signal output by the identification signal output end can be determined according to the resistance value of the ninth resistor, the eighth voltage end and the ninth voltage end.

Or, the other end of the ninth resistor R9 is connected to the identification signal output end and one end of the tenth resistor R10, respectively, and the other end of the tenth resistor R10 is connected to the ninth voltage end U9.

The compressor identification signal output by the identification signal output terminal may be determined according to the resistance values of the ninth resistor R9 and the tenth resistor R10 and the voltages of the eighth voltage terminal U8 and the ninth voltage terminal U9.

Or, one end of the tenth resistor R10 is connected to the eighth voltage terminal U9 and the identification signal output terminal, respectively, and the other end of the tenth resistor R10 is connected to the ninth voltage terminal.

The compressor identification signal output by the identification signal output end can be determined according to the resistance value of the tenth resistor, the voltages of the eighth voltage end and the ninth voltage end.

In this embodiment, the ninth resistor and/or the tenth resistor are/is connected in series on the loop, so that the identification signal output end outputs the compressor identification signal to the processor according to the resistance value of the ninth resistor and/or the tenth resistor and the voltages of the eighth voltage end and the ninth voltage end, so that the processor can accurately identify the compressor, the processor can accurately control the compressor driving circuit, and the safety and reliability of the variable frequency control circuit can be improved.

Optionally, fig. 11 shows a schematic structural diagram of a further compressor identification signal input unit, as shown in fig. 11, where the identification signal input unit 204 further includes an eleventh resistor R11, where the eleventh resistor R11 is connected in series to the identification signal output end, and the eleventh resistor may be a current limiting resistor, so as to prevent the processor from being damaged due to excessive current on a branch where the eleventh resistor is located, so as to improve safety and reliability of the frequency conversion control circuit.

Fig. 12 shows a schematic structural diagram of yet another compressor identification signal input unit, and as shown in fig. 12, the compressor identification signal input unit 201 includes a seventh resistor R7 and an eighth resistor R8.

One end of the seventh resistor R7 is connected with the processor 201, and the other end of the seventh resistor R7 is connected with the four-terminal socket; one end of the eighth resistor R8 is connected with the processor 201, the other end of the eighth resistor R8 is connected with the four-end socket, the seventh resistor and the eighth resistor can be current limiting resistors, the damage to the four-end socket and the processor caused by overlarge branch circuits where the seventh resistor and the eighth resistor are located is prevented, through the connection, the processor and the four-end socket interact in an asynchronous serial communication mode, namely, the processor sends a request signal for requesting a compressor identification signal to the four-end socket, and the four-end socket returns the compressor identification signal to the processor according to the request signal, so that the processor can accurately identify the compressor according to the compressor identification signal, the processor can accurately control a compressor driving circuit, and the reliability of the variable frequency control circuit is improved.

Optionally, fig. 13 shows a schematic structural diagram of a further compressor identification signal input unit, as shown in fig. 13, the compressor identification signal input unit 204 includes a twelfth resistor R12, one end of the twelfth resistor R12 is connected to the processor 201, and the other end of the twelfth resistor R12 is connected to a three-terminal socket, where the twelfth resistor may be a sliding rheostat, and the compressor identification signal may be sent to the processor by adjusting the resistance of the twelfth resistor, so that the processor accurately identifies the compressor, which is beneficial for the processor to accurately control the compressor driving circuit and improve the reliability of the variable frequency control circuit.

Fig. 14 shows a schematic structural diagram of a refrigerator, as shown in fig. 14, including any of the frequency conversion control circuits 20 of the above embodiments.

It will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-described division of the functional units and modules is illustrated, and in practical application, the above-described functional distribution may be performed by different functional units and modules according to needs, i.e. the internal structure of the apparatus is divided into different functional units or modules to perform all or part of the above-described functions.

The above embodiments are only for illustrating the technical solution of the present utility model, and not for limiting the same; although the utility model has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present utility model, and are intended to be included in the scope of the present utility model.

Claims (10)

1. A power supply circuit, comprising:

the collector of the triode is connected with the first voltage end, the base of the triode is respectively connected with the first voltage end and the second voltage end, and the emitter of the triode is respectively connected with the third voltage end and the power utilization circuit;

the grid electrode of the field effect tube is connected with the first voltage end, the source electrode of the field effect tube is connected with the second voltage end, and the drain electrode of the field effect tube is connected with the fourth voltage end.

2. The power supply circuit of claim 1, wherein the power supply circuit further comprises:

one end of the first resistor is connected with the collector electrode of the triode, and the other end of the first resistor is connected with the first voltage end;

one end of the second resistor is connected with one end of the first resistor, and the other end of the second resistor is connected with the base electrode of the third transistor;

the cathode of the first diode is connected with the other end of the second resistor, and the anode of the first diode is connected with the second voltage end;

one end of the first capacitor is connected with the base electrode of the triode, and the other end of the first capacitor is connected with the second voltage end;

one end of the second capacitor is connected with the emitter of the triode, and the other end of the second capacitor is connected with the second voltage end;

and one end of the third capacitor is connected with the emitter of the triode, and the other end of the third capacitor is connected with the second voltage end.

3. The power supply circuit of claim 1, wherein the power supply circuit further comprises:

one end of the third resistor is connected with the first voltage end, and the other end of the third resistor is connected with the grid electrode of the field effect tube;

one end of the fourth capacitor is connected with the first voltage end, and the other end of the fourth capacitor is connected with the source electrode of the field effect transistor;

and the cathode of the second diode is connected with the grid electrode of the field effect tube, and the anode of the second diode is connected with the source electrode of the field effect tube.

4. A variable frequency control circuit, comprising:

the processor is used for receiving and processing the external signal, generating a control signal and transmitting the control signal;

the compressor driving circuit is connected with the processor and is used for receiving the control signal and driving the compressor according to the control signal;

a power supply circuit as claimed in any one of claims 1 to 3, connected to the processor and the compressor drive circuit, respectively, for powering the compressor drive circuit and the processor.

5. The variable frequency control circuit of claim 4, wherein the variable frequency control circuit further comprises:

and the compressor rotating speed signal input unit is connected with the processor and is used for inputting a compressor rotating speed control signal to the processor so that the processor controls the compressor driving unit according to the compressor rotating speed control signal.

6. The variable frequency control circuit of claim 5, wherein the compressor rotational speed signal input unit comprises:

one end of the fourth resistor is used for receiving a compressor rotating speed control signal;

the first end of the first optocoupler is connected with the other end of the fourth resistor, the second end of the first optocoupler is connected with a fifth voltage end, and the fourth end of the first optocoupler is connected with a sixth voltage end;

the first end of the second optocoupler is connected with the fifth voltage end, the second end of the second optocoupler is connected with the other end of the fourth resistor, and the fourth end of the second optocoupler is connected with the sixth voltage end;

one end of the fifth resistor is connected with the processor, and the other end of the fifth resistor is respectively connected with the third end of the first optocoupler and the third end of the second optocoupler;

one end of the sixth resistor is connected with the third end of the first optocoupler, and the second end of the sixth resistor is connected with a seventh voltage end;

and one end of the fifth capacitor is connected with the other end of the fifth resistor, and the second end of the fifth capacitor is connected with the seventh voltage end.

7. The variable frequency control circuit of claim 4, further comprising:

and the compressor identification signal input unit is connected with the processor and is used for inputting a compressor identification signal to the processor so that the processor can identify the compressor according to the compressor identification signal.

8. The variable frequency control circuit of claim 7, wherein the compressor identification signal input unit comprises:

an eighth voltage terminal and a ninth voltage terminal, wherein the eighth voltage terminal is connected with the ninth voltage terminal to form a loop;

and the identification signal output end is arranged on the loop and used for outputting a compressor identification signal to the processor.

9. The variable frequency control circuit of claim 7, wherein the compressor identification signal input unit comprises: one end of the seventh resistor is connected with the processor, and the other end of the seventh resistor is connected with a four-terminal socket;

and one end of the eighth resistor is connected with the processor, and the other end of the eighth resistor is connected with the four-terminal socket.

10. A refrigerator comprising the variable frequency control circuit according to any one of claims 4 to 9.