Overvoltage protection module, controller, vehicle-mounted air conditioner and vehicle

Abstract

The utility model discloses an overvoltage protection module, a controller, a vehicle-mounted air conditioner and a vehicle, and relates to the technical field of protection circuits. The circuit comprises a sampling circuit, a voltage comparator and a voltage change-over switch circuit. The first input end of the voltage comparator is coupled with the voltage output end of the sampling circuit. The voltage conversion switch circuit is coupled between the second input end and the comparison output end of the voltage comparator, the voltage conversion switch circuit is coupled with the load, and the reference voltage input by the second input end is converted through the output level of the voltage comparator so as to form double-threshold overvoltage protection on the load. Therefore, when the voltage is higher than the first reference voltage, the load is controlled to be powered off for overvoltage protection, and when the voltage is lower than the second reference voltage, the load is controlled to be powered on for work. Therefore, the problem of frequent start and stop of the transistor caused by fluctuation of the voltage at the protection voltage threshold is avoided, and the reliability of load overvoltage protection and the stability of load operation are improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of protection circuit, especially to an overvoltage protection module, a controller, a vehicle-mounted air conditioner and a vehicle. BACKGROUND

[0002] In some circuits for controlling electrical equipment to operate by direct current voltage, the electrical equipment needs to consume extra power to operate, especially in some application scenarios where extra power is consumed more, when the electrical equipment starts or stops, a large voltage fluctuation will be generated, which may cause the internal control device of the electrical equipment load to be overvoltage and damage the equipment.

[0003] Currently, the overvoltage protection of the equipment is usually formed by combining a comparator and a transistor, but when the overvoltage value fluctuates at the protection voltage threshold set by the comparator, the transistor will be frequently started and stopped, thereby reducing the reliability of the overvoltage protection of the load. SUMMARY

[0004] In view of the problem that the frequent start and stop of the transistor caused by the fluctuation of the voltage at the protection voltage threshold reduces the reliability of the overvoltage protection of the load, the utility model is proposed in order to provide an overvoltage protection module, a controller, a vehicle-mounted air conditioner and a vehicle which overcome the above problems or at least partially solve the above problems.

[0005] Based on the first aspect of the utility model, an overvoltage protection module is provided, which comprises:

[0006] a sampling circuit, which is coupled with a direct current voltage power supply end of a load to detect the working voltage of the load;

[0007] a voltage comparator, a first input end of which is coupled with a voltage output end of the sampling circuit;

[0008] a voltage conversion switch circuit, which is coupled between a second input end and a comparison output end of the voltage comparator, wherein the voltage conversion switch circuit is coupled with the load, and the reference voltage input by the second input end is converted by the output level of the voltage comparator to form a double-threshold overvoltage protection for the load.

[0009] An optional utility model content, the voltage conversion switch circuit comprises:

[0010] a first transistor, a first pole of which is coupled with the comparison output end of the voltage comparator, and a second pole of which is coupled with the load to control the power-on state of the load by the first transistor;

[0011] a second transistor, a first pole of the second transistor being coupled with a comparison output end of the voltage comparator, a second pole of the second transistor being coupled with a second input end of the voltage comparator;

[0012] a first feedback resistor, one end of the first feedback resistor being coupled with a third pole of the second transistor;

[0013] a second feedback resistor, one end of the second feedback resistor being coupled with a voltage stabilizing power supply, and the other end being coupled with the second pole of the second transistor;

[0014] a third feedback resistor, one end of the third feedback resistor being coupled with the other end of the first feedback resistor and then grounded, and the other end being coupled with the second pole of the second transistor.

[0015] An optional utility model content, the first transistor is NPN triode, the second transistor is PNP triode, wherein, the first pole of the first transistor is base, the second pole of the first transistor is collector;

[0016] the first pole of the second transistor is base, and the second pole of the second transistor is emitter.

[0017] An optional utility model content, the first transistor is PNP triode, the second transistor is NPN triode, wherein, the first pole of the first transistor is base, the second pole of the first transistor is collector;

[0018] the first pole of the second transistor is base, and the second pole of the second transistor is collector.

[0019] An optional utility model content, the first transistor is N-type MOS tube, the second transistor is P-type MOS tube, wherein, the first pole of the first transistor is gate, the second pole of the first transistor is drain;

[0020] the first pole of the second transistor is gate, and the second pole of the second transistor is source.

[0021] An optional utility model content, the first transistor is P-type MOS tube, the second transistor is N-type MOS tube, wherein, the first pole of the first transistor is gate, the second pole of the first transistor is source;

[0022] the first pole of the second transistor is gate, and the second pole of the second transistor is drain.

[0023] An optional utility model content, the overvoltage protection module further includes a current limiting resistor, the current limiting resistor is coupled between the comparison output end of the voltage comparator and the first pole of the first transistor.

[0024] Optionally, the sampling circuit comprises a first sampling resistor and a second sampling resistor, wherein the first sampling resistor and the second sampling resistor are connected in series, and a connection between the first sampling resistor and the second sampling resistor is a voltage output terminal of the sampling circuit, one end of the second sampling resistor away from the first sampling resistor is grounded, and one end of the first sampling resistor away from the second sampling resistor is coupled with a DC voltage supply terminal of the load.

[0025] Optionally, when at least two first feedback resistors are provided, the at least two first feedback resistors are connected in series.

[0026] Optionally, when at least two second feedback resistors are provided, the at least two second feedback resistors are connected in series.

[0027] Optionally, when at least two third feedback resistors are provided, the at least two third feedback resistors are connected in series.

[0028] According to the second aspect of the utility model, a controller is further provided, and the controller comprises the overvoltage protection module according to any one of the utility model contents.

[0029] According to the third aspect of the utility model, a vehicle-mounted air conditioner is further provided, and the vehicle-mounted air conditioner comprises the controller according to the utility model content, and the sampling circuit is coupled with a DC voltage supply terminal of a fan.

[0030] According to the fourth aspect of the utility model, a vehicle is further provided, and the vehicle comprises the vehicle-mounted air conditioner according to the utility model content.

[0031] Compared with the prior art, the utility model discloses sampling circuit, voltage comparator and voltage conversion switch circuit. Sampling circuit and the DC voltage power supply end of load form coupling to detect the operating voltage of load. The first input of voltage comparator is coupled with the voltage output of sampling circuit. Voltage conversion switch circuit is coupled between the second input and comparison output of voltage comparator, wherein, voltage conversion switch circuit forms coupling with load, and through the output level of voltage comparator, the reference voltage of second input is converted to form double threshold overvoltage protection to load. Therefore, through setting two reference voltages, when voltage is higher than first reference voltage, the load is controlled to power off and carries out overvoltage protection, and when voltage is lower than second reference voltage, the load is controlled to power on and carries out work. Therefore, when detecting that voltage is lower than second reference voltage, overvoltage protection is exited, the problem of frequent start and stop of transistor caused by voltage fluctuation at protection voltage threshold is avoided, thereby improve the reliability of load overvoltage protection and load operation stability.

[0032] The above description is only a summary of the technical scheme of the utility model, in order to more clearly understand the technical means of the utility model, can be implemented according to the content of the specification, and in order to let the above and other purposes, characteristics and advantages of the utility model can be more obvious and easy to understand, the following specific embodiment of the utility model is described. BRIEF DESCRIPTION OF DRAWINGS

[0033] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a description of the preferred embodiments and are not meant to limit the present utility model. Moreover, the same reference numerals in the various drawings indicate the same or similar elements.

[0034] In the drawings:

[0035] Figure 1 It is the structure block diagram of the overvoltage protection module provided by the utility model embodiment;

[0036] Figure 2 It is the circuit structure schematic view of another overvoltage protection module provided by the utility model embodiment;

[0037] Figure 3 It is the circuit structure schematic view of another overvoltage protection module provided by the utility model embodiment;

[0038] Figure 4 It is the circuit structure schematic view of another overvoltage protection module provided by the utility model embodiment;

[0039] Figure 5 It is the circuit structure schematic view of another overvoltage protection module provided by the utility model embodiment;

[0040] Label: 1, sampling circuit; 101, first sampling resistor; 102, second sampling resistor; 2, voltage comparator; 3, voltage conversion switch circuit; 301, first transistor; 302, second transistor; 303, first feedback resistor; 304, second feedback resistor; 305, third feedback resistor; 4, current limiting resistor; 5, load. DETAILED DESCRIPTION

[0041] Exemplary embodiments of the present application will be described herein below with reference to the accompanying drawings. While exemplary embodiments of the present application are shown in the drawings, it is understood that the present application can be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present application to those skilled in the art.

[0042] In some circuits for controlling electrical devices to operate with direct current voltage, additional power is consumed by the operation of the electrical devices, especially in some application scenarios where additional power is consumed in large amounts. When the electrical devices are started or stopped, large voltage fluctuations are generated, which may cause the internal control components of the electrical device load to be overvoltage, resulting in damage to the device.

[0043] Currently, a comparator and a transistor are usually combined to form overvoltage protection for the device. However, when the overvoltage value fluctuates at the protection voltage threshold set by the comparator, the transistor is frequently started and stopped, thereby reducing the reliability of the overvoltage protection for the load.

[0044] Based on the above technical problems, the present application embodiment is proposed, which can include a sampling circuit 1, a voltage comparator 2, and a voltage conversion switch circuit 3. The sampling circuit 1 is coupled with a direct current voltage power supply end of a load 5 to detect the operating voltage of the load 5. A first input end of the voltage comparator 2 is coupled with a voltage output end of the sampling circuit 1. The voltage conversion switch circuit 3 is coupled between a second input end and a comparison output end of the voltage comparator 2, wherein the voltage conversion switch circuit 3 is coupled with the load 5, and the reference voltage input by the second input end is converted by the output level of the voltage comparator 2 to form double-threshold overvoltage protection for the load 5. Thus, by setting two reference voltages, when the voltage is higher than the first reference voltage, the load 5 is controlled to be powered off for overvoltage protection, and when the voltage is lower than the second reference voltage, the load 5 is controlled to be powered on for operation. Thus, overvoltage protection is exited only when the voltage is detected to be lower than the second reference voltage, avoiding the problem of frequent starting and stopping of the transistor caused by the fluctuation of the voltage at the protection voltage threshold, thereby improving the reliability of the overvoltage protection for the load 5 and the operating stability of the load 5.

[0045] With reference to Figure 1 The utility model embodiment provides a kind of overvoltage protection module, the overvoltage protection module can include sampling circuit 1, voltage comparator 2 and voltage conversion switch circuit 3.Sampling circuit 1 is coupled with the dc voltage power supply end of load 5, to detect the operating voltage of load 5.The first input end of voltage comparator 2 is coupled with the voltage output end of sampling circuit 1.Voltage conversion switch circuit 3 is coupled between the second input end and comparison output end of voltage comparator 2, wherein, voltage conversion switch circuit 3 is coupled with load 5, and the reference voltage input by the second input end is converted by the output level of voltage comparator 2, to form double threshold overvoltage protection to load 5.

[0046] In the utility model embodiment, the overvoltage protection module can include sampling circuit 1, comparator and voltage conversion switch circuit 3.The voltage input end of sampling circuit 1 is coupled with the dc voltage power supply end of load 5 of vehicle-mounted air conditioner, so that the operating voltage of load 5 can be detected by sampling circuit 1.

[0047] The voltage comparator 2 has two input ends, and the first input end of the voltage comparator 2 is coupled with the voltage output end of the sampling circuit 1. The voltage conversion switch circuit 3 is coupled between the second output end of the voltage comparator 2 and the comparison output end of the voltage comparator 2, wherein the voltage conversion switch circuit 3 can control the power-on state of the load 5 and can convert the reference voltage value input to the second input end of the voltage comparator 2, so that double threshold overvoltage protection can be formed to the load 5 by setting two reference voltages.

[0048] When the voltage is higher than the first reference voltage, the voltage comparator 2 outputs a target level to control the voltage conversion switch circuit 3 to adjust the load 5 to be powered off for overvoltage protection. When the voltage is lower than the second reference voltage, the voltage comparator 2 outputs a level opposite to the target level to control the voltage conversion switch circuit 3 to perform switching action to adjust the load 5 to be powered on for work. Thus, overvoltage protection is exited only when it is detected that the voltage is lower than the second reference voltage, avoiding the problem of frequent start and stop of the transistor caused by voltage fluctuation at the protection voltage threshold of the load 5, thereby improving the reliability of overvoltage protection of the load 5 and the running stability of the load 5.

[0049] An alternative utility model embodiment, with reference to Figure 2 、 Figure 3 、 Figure 4 and Figure 5As shown, the voltage conversion switch circuit 3 can include a first transistor 301, a second transistor 302, a first feedback resistor 303, a second feedback resistor 304, and a third feedback resistor 305. A first pole of the first transistor 301 is coupled with a comparison output end of the voltage comparator 2. And, a second pole of the first transistor 301 is coupled with the load 5 to control the energization state of the load 5 through the first transistor 301. A first pole of the second transistor 302 is coupled with the comparison output end of the voltage comparator 2, and a second pole of the second transistor 302 is coupled with a second input end of the voltage comparator 2.

[0050] One end of the first feedback resistor 303 is coupled with a third pole of the second transistor 302. One end of the second feedback resistor 304 is coupled with a voltage stabilizing power supply, and the other end is coupled with the second pole of the second transistor 302. One end of the third feedback resistor 305 is coupled with the other end of the first feedback resistor 303 and grounded, and the other end is coupled with the second pole of the second transistor 302.

[0051] In the embodiment of the utility model, the voltage conversion switch circuit 3 can include a first transistor 301, a second transistor 302, a first feedback resistor 303, a second feedback resistor 304, and a third feedback resistor 305. Wherein, the first transistor 301 and the second transistor 302 can adopt triode or field effect transistor and other semiconductor switching devices. The first pole of the first transistor 301, the first pole of the second transistor 302 are coupled with the comparison output end of the voltage comparator 2 respectively, so that the high level or low level output by the comparison output end of the voltage comparator 2 can control the first transistor 301 and the second transistor 302 to be turned on or cut off. Wherein, the working state of the first transistor 301 and the second transistor 302 is different in the same time period.

[0052] For example, if the comparison output end of the voltage comparator 2 outputs high level, and the first transistor 301 is in cut-off state, then the second transistor 302 is in turn-on state. If the comparison output end of the voltage comparator 2 outputs high level, and the first transistor 301 is in turn-on state, then the second transistor 302 is in cut-off state. If the comparison output end of the voltage comparator 2 outputs low level, and the first transistor 301 is in cut-off state, then the second transistor 302 is in turn-on state. If the comparison output end of the voltage comparator 2 outputs low level, and the first transistor 301 is in turn-on state, then the second transistor 302 is in cut-off state.

[0053] In some embodiments, the second pole of the first transistor 301 is coupled with the load 5, so that when the first transistor 301 is in the on state, the working circuit of the load 5 is powered on, ensuring that the load 5 is powered on and operates. When the first transistor 301 is in the off state, the working circuit of the load 5 is powered off, ensuring that the load 5 is powered off and stops operating. Thus, the power-on state of the load 5 can be controlled by the first transistor 301, so that overvoltage protection can be achieved in time.

[0054] The second pole of the second transistor 302 is coupled with the second input terminal of the voltage comparator 2, one end of the first feedback resistor 303 is coupled with the third pole of the second transistor 302. One end of the second feedback resistor 304 is coupled with the voltage stabilizing power supply, and the other end of the second feedback resistor 304 is coupled with the second pole of the second transistor 302. One end of the third feedback resistor 305 is coupled with the other end of the first feedback resistor 303 and then grounded, and the other end of the third feedback resistor 305 is coupled with the second pole of the second transistor 302. In other words, the first feedback resistor 303 and the third feedback resistor 305 are arranged in parallel. The switching state of the second transistor 302 controls the on-off of the parallel circuit in which the first feedback resistor 303 is located.

[0055] If the second transistor 302 is in the off state, the parallel circuit in which the first feedback resistor 303 is located is disconnected, at this time the second feedback resistor 304 and the third feedback resistor 305 form a series connection, and the voltage at the connection of the second feedback resistor 304 and the third feedback resistor 305, i.e. the first reference voltage of the second input terminal of the voltage comparator 2.

[0056] If the second transistor 302 is in the on state, the first feedback resistor 303 and the third feedback resistor 305 form a parallel connection, and then form a series connection with the second feedback resistor 304. At this time, the voltage at the connection of the first feedback resistor 303 and the second feedback resistor 304 is the second reference voltage of the second input terminal of the voltage comparator 2. The second reference voltage is less than the first reference voltage. Thus, the first feedback resistor 303, the second feedback resistor 304, the third feedback resistor 305, the second transistor 302, and the voltage comparator 2 can form a hysteresis comparator in combination, and by setting two reference voltages, when the voltage is higher than the first reference voltage, it is determined that the working voltage of the load 5 is too high and there is a risk of damage, and the load 5 is controlled to be powered off for overvoltage protection, and when the voltage is lower than the second reference voltage, the load 5 is controlled to be powered on for work. Therefore, overvoltage protection is exited only when the voltage is detected to be lower than the second reference voltage, avoiding the problem of frequent start and stop of the transistor caused by the fluctuation of the working voltage at the protection voltage threshold, thereby improving the reliability of the overvoltage protection of the load 5 and the running stability of the load 5.

[0057] An optional utility model embodiment is shown in Figure 2 The first input terminal of the voltage comparator 2 can be an inverting input terminal, and the second input terminal of the voltage comparator 2 can be a non-inverting input terminal. The first transistor 301 is an NPN bipolar junction transistor (NPN Bipolar Junction Transistor, NPN type bipolar junction transistor), and the second transistor 302 is a PNP bipolar junction transistor (PNP Bipolar Junction Transistor, PNP type bipolar junction transistor). Among them, the first pole of the first transistor 301 is the base, the second pole of the first transistor 301 is the collector C, and the third pole of the first transistor 301 is the emitter E. The third pole of the first transistor 301 can be grounded, and the load 5 can be connected in series between the second pole of the first transistor 301 and the direct current voltage supply end.

[0058] The first pole of the second transistor 302 is the base B, the second pole of the second transistor 302 is the emitter E, the third pole of the second transistor 302 is the collector C, and the third pole of the second transistor 302 is coupled with the first feedback resistor 303 to ground. Thus, when the voltage of the DC power supply terminal is greater than the first reference voltage, the voltage comparator 2 outputs low level. At this time, the first transistor 301 is in the off state under the low level drive, and the load 5 stops working. The second transistor 302 is in the on state under the low level drive, and at this time, the first feedback resistor 303 and the third feedback resistor 305 form a parallel connection, thereby reducing the reference voltage of the second input terminal of the voltage comparator 2 through the parallel connection of resistors, and converting the reference voltage from the first reference voltage to the second reference voltage. When the voltage of the DC power supply terminal is detected to be between the first reference voltage and the second reference voltage, the voltage comparator 2 keeps outputting low level, the first transistor 301 continues to keep the off state, and the load 5 keeps being powered off.

[0059] Until the voltage of the DC power supply terminal is detected to be less than the second reference voltage, the comparison output terminal of the voltage comparator 2 outputs high level, and the first transistor 301 is in the on state under the high level drive. At this time, the load 5 is powered on and works. The second transistor 302 is in the off state under the high level drive, and at this time, the parallel connection of the first feedback resistor 303 is disconnected, the reference voltage of the second input terminal of the voltage comparator 2 is increased, and the reference voltage is converted from the second reference voltage to the first reference voltage. Wherein, the quotient obtained by dividing the voltage value provided by the voltage stabilizing power supply by the cumulative resistance value of the second feedback resistor 304 and the third feedback resistor 305, and then multiplying the resistance value of the third feedback resistor 305, is the first reference voltage.

[0060] The second reference voltage can be determined by the following calculation method: first, calculate the parallel resistance value of the first feedback resistor 303 and the third feedback resistor 305 in parallel. Then determine the cumulative resistance value obtained by adding the second feedback resistor 304 and the parallel resistance value, and then divide the voltage value provided by the voltage stabilizing power supply by the cumulative resistance value to obtain the quotient, and then multiply the parallel resistance value to obtain the second reference voltage.

[0061] An alternative embodiment of the utility model, refer to Figure 3As shown, the first input end of the voltage comparator 2 can be a non-inverting input end, and the second input end of the voltage comparator 2 can be an inverting input end. The first transistor 301 is a PNP transistor, and the second transistor 302 is an NPN transistor. The first pole of the first transistor 301 is a base B, and the second pole of the first transistor 301 is a collector C. The first pole of the second transistor 302 is a base B, and the second pole of the second transistor 302 is a collector C.

[0062] In the embodiment of the utility model, the first transistor 301 is a PNP transistor, and the second transistor 302 is an NPN transistor. The first pole of the first transistor 301 is a base B, the second pole of the first transistor 301 is a collector C, and the third pole of the first transistor 301 is an emitter E. The third pole of the first transistor 301 can be coupled with a direct-current voltage supply end, and the load 5 can be connected in series between the second pole of the first transistor 301 and a ground end.

[0063] The first pole of the second transistor 302 is a base B, the second pole of the second transistor 302 is a collector, the third pole of the second transistor 302 is an emitter E, and the third pole of the second transistor 302 is coupled with the first feedback resistor 303 and then grounded. Thus, when the voltage of the direct-current voltage supply end is detected to be greater than the first reference voltage, the voltage comparator 2 outputs a high level. At this time, the first transistor 301 enters an off state under high-level driving, and the load 5 stops working. The second transistor 302 enters an on state under high-level driving, and at this time, the first feedback resistor 303 and the third feedback resistor 305 form a parallel connection, thereby reducing the reference voltage of the second input end of the voltage comparator 2 through resistance parallel connection and converting the reference voltage from the first reference voltage to the second reference voltage. When the voltage of the direct-current supply end is detected to drop to a voltage value between the first reference voltage and the second reference voltage, the voltage comparator 2 keeps outputting a high level, the first transistor 301 continues to keep an off state, and the load 5 keeps being powered off.

[0064] Until the voltage of the direct-current supply end is detected to be less than the second reference voltage, the comparison output end of the voltage comparator 2 outputs a low level, and the first transistor 301 enters an on state under low-level driving. At this time, the load 5 is powered on and works. The second transistor 302 enters an off state under low-level driving, and at this time, the parallel connection of the first feedback resistor 303 is disconnected, the reference voltage of the second input end of the voltage comparator 2 is raised, and the reference voltage is converted from the second reference voltage to the first reference voltage.

[0065] An optional embodiment of the utility model, referring to Figure 4As shown, the first input end of the voltage comparator 2 can be an inverting input end, and the second input end of the voltage comparator 2 can be a non-inverting input end. The first transistor 301 is an N-type MOS transistor, and the second transistor 302 is a P-type MOS transistor, wherein the first pole of the first transistor 301 is a gate G, and the second pole of the first transistor 301 is a drain D. The first pole of the second transistor 302 is a gate G, and the second pole of the second transistor 302 is a source S.

[0066] In the embodiment of the utility model, the first transistor 301 is an N-type MOS transistor, and the second transistor 302 is a P-type MOS transistor, wherein the first pole of the first transistor 301 is a gate G, the second pole of the first transistor 301 is a drain D, and the third pole of the first transistor 301 is a source S. The third pole of the first transistor 301 can be grounded, and the load 5 can be connected in series between the second pole of the first transistor 301 and the DC voltage supply end.

[0067] The first pole of the second transistor 302 is a gate G, the second pole of the second transistor 302 is a source S, the third pole of the second transistor 302 is a drain D, and the third pole of the second transistor 302 is grounded after being coupled with the first feedback resistor 303. Thus, when the voltage of the DC voltage supply end is detected to be greater than the first reference voltage, the voltage comparator 2 outputs a low level. At this time, the first transistor 301 enters an off state under low-level driving, and the load 5 stops working. The second transistor 302 enters an on state under low-level driving, and at this time, the first feedback resistor 303 and the third feedback resistor 305 form a parallel connection, thereby reducing the reference voltage of the second input end of the voltage comparator 2 through the parallel connection of resistors and converting the reference voltage from the first reference voltage to the second reference voltage. When the voltage of the DC supply end is detected to drop to a voltage value between the first reference voltage and the second reference voltage, the voltage comparator 2 keeps outputting a low level, the first transistor 301 continues to keep an off state, and the load 5 keeps being powered off.

[0068] Until the voltage of the direct current power supply end is detected to be less than the second reference voltage, the comparison output end of the voltage comparator 2 outputs a high level, the first transistor 301 is in the conductive state under the driving of the high level, and the load 5 is powered on to work.

[0069] An optional utility model content, referring to Figure 5 As shown in the figure, the first input end of the voltage comparator 2 can be a same-phase input end, and the second input end of the voltage comparator 2 can be an inverse-phase input end. The first transistor 301 is a P-type MOS tube, and the second transistor 302 is an N-type MOS tube, wherein the first pole of the first transistor 301 is a gate G, and the second pole of the first transistor 301 is a source S. The first pole of the second transistor 302 is a gate G, and the second pole of the second transistor 302 is a drain D.

[0070] In the embodiment of the utility model, the first transistor 301 is a P-type MOS tube, and the second transistor 302 is an N-type MOS tube, wherein the first pole of the first transistor 301 is a gate G, the second pole of the first transistor 301 is a source S, and the third pole of the first transistor 301 is a drain D, wherein the load 5 can be connected in series between the third pole of the first transistor 301 and the ground end.

[0071] The first pole of the second transistor 302 is a gate G, the second pole of the second transistor 302 is a drain D, and the third pole of the second transistor 302 is a source S, wherein the third pole of the second transistor 302 is coupled with the first feedback resistor 303 and then grounded. Thus, when the voltage of the direct current voltage supply end is detected to be greater than the first reference voltage, the voltage comparator 2 outputs a high level. At this time, the first transistor 301 is in the cut-off state under the driving of the high level, and the load 5 stops working. The second transistor 302 is in the conductive state under the driving of the high level, at this time, the first feedback resistor 303 and the third feedback resistor 305 form a parallel connection, thereby reducing the reference voltage of the second input end of the voltage comparator 2 in the form of resistance parallel connection, and converting the reference voltage from the first reference voltage to the second reference voltage. When the voltage of the direct current power supply end is detected to be reduced to a voltage value between the first reference voltage and the second reference voltage, the voltage comparator 2 keeps outputting a high level, the first transistor 301 continues to keep the cut-off state, and the load 5 keeps being powered off.

[0072] Until the voltage of the direct current power supply end is detected to be less than the second reference voltage, the comparison output end of the voltage comparator 2 outputs a low level, the first transistor 301 is in an on state under low level driving, at this time, the load 5 is powered on and works.

[0073] In the above-mentioned utility model embodiments, the first transistor 301 and the second transistor 302 are both triodes or MOS tubes, which are used to improve the processing convenience. In some embodiments, the first transistor 301 is an NPN triode, and the second transistor 302 is a P-type MOS tube. Alternatively, the first transistor 301 is an N-type MOS tube, and the second transistor 302 is a PNP triode. Alternatively, the first transistor 301 is a P-type MOS tube, and the second transistor 302 is an NPN triode. Alternatively, the first transistor 301 is a PNP triode, and the second transistor 302 is an N-type MOS tube. Those skilled in the art can determine the type combination of the first transistor 301 and the second transistor 302 according to actual design requirements, which is not limited herein.

[0074] An optional utility model embodiment, referring to Figures 2-5 The overvoltage protection module further includes a current limiting resistor 4, which is coupled between the comparison output end of the voltage comparator 2 and the first pole of the first transistor 301.

[0075] In the above-mentioned utility model embodiments, the overvoltage protection module can further include a current limiting resistor 4, which is located between the comparison output end of the voltage comparator 2 and the first pole of the first transistor 301. Alternatively, the current limiting resistor 4 is located between the comparison output end of the voltage comparator 2 and the second pole of the second transistor 302. The current limiting resistor 4 can limit the current flowing into the first transistor 301 and the second transistor 302, thereby protecting the first transistor 301 and the second transistor 302 and ensuring the working stability of the first transistor 301 and the second transistor 302.

[0076] An optional utility model embodiment, referring to Figures 2-5As shown, the sampling circuit 1 comprises a first sampling resistor 101 and a second sampling resistor 102, wherein the first sampling resistor 101 and the second sampling resistor 102 are connected in series, and the connection of the first sampling resistor 101 and the second sampling resistor 102 is the voltage output end of the sampling circuit 1, one end of the second sampling resistor 102 is grounded, and the other end of the first sampling resistor 101 is coupled with the DC voltage supply end of the load 5.

[0077] In the embodiment of the utility model, the sampling circuit 1 can include a first sampling resistor 101 and a second sampling resistor 102. The first sampling resistor 101 and the second sampling resistor 102 are connected in series. For example, one end of the first sampling resistor 101 can be coupled with the DC voltage supply end, and the other end can be coupled with the second sampling resistor 102. In this way, the connection of the first sampling resistor 101 and the second sampling resistor 102 can serve as the voltage output end of the sampling circuit 1 and be coupled with the first input end of the voltage comparator 2. The other end of the second sampling resistor 102 is grounded. Thus, the comparison result between the voltage Vi output by the voltage output end of the sampling circuit 1 and the reference voltage Vref can be used to detect whether the voltage VI output by the DC voltage supply end is greater than the overvoltage protection threshold. The voltage conversion switch circuit 3 is driven to act, and overvoltage protection of the load 5 is realized.

[0078] In an optional embodiment of the utility model, when at least two first feedback resistors 303 are provided, the at least two first feedback resistors 303 are connected in series. When at least two second feedback resistors 304 are provided, the at least two second feedback resistors 304 are connected in series. When at least two third feedback resistors 305 are provided, the at least two third feedback resistors 305 are connected in series.

[0079] In the embodiment of the utility model, the first feedback resistor 303 can be provided in multiple, the second feedback resistor 304 can also be provided in multiple, and the third feedback resistor 305 can also be provided in multiple. When the first feedback resistor 303 is provided in at least two, the at least two first feedback resistors 303 are connected in series. When the second feedback resistor 304 is provided in at least two, the at least two second feedback resistors 304 are connected in series. When the third feedback resistor 305 is provided in at least two, the at least two third feedback resistors 305 are connected in series. Those skilled in the art can determine the number of first feedback resistors 303, the number of second feedback resistors 304, and the number of third feedback resistors 305 according to the threshold voltage of overvoltage protection and the resistance value of the feedback resistor, which is not limited here.

[0080] In summary, the utility model discloses a kind of overvoltage protection modules, the overvoltage protection module can include sampling circuit 1, voltage comparator 2 and voltage conversion switch circuit 3. The sampling circuit 1 is coupled with the dc voltage power supply end of load 5, to detect the operating voltage of the load 5. The first input end of the voltage comparator 2 is coupled with the voltage output end of the sampling circuit 1. The voltage conversion switch circuit 3 is coupled between the second input end and comparison output end of the voltage comparator 2, wherein the voltage conversion switch circuit 3 is coupled with load 5, and the reference voltage input by the second input end is converted by the output level of the voltage comparator 2, to form double-threshold overvoltage protection to the load 5. So as to set two reference voltages, when voltage is higher than the first reference voltage, control the load 5 power-off to carry out overvoltage protection, when voltage is lower than the second reference voltage, control the load 5 power-on to work. So as to detect voltage lower than the second reference voltage to exit overvoltage protection, avoid the frequent start-stop problem of transistor caused by voltage fluctuation at protection voltage threshold, thereby improve the reliability of load 5 overvoltage protection and load 5 running stability. And, the overvoltage protection module can be widely applied to some overvoltage protection required direct current circuit.

[0081] The utility model embodiment further discloses a controller, and the controller comprises the overvoltage protection module according to any one of the preceding embodiments.

[0082] In the utility model embodiment, the controller comprises the overvoltage protection module according to any one of the preceding embodiments. The controller can further integrate other functional modules in addition to the overvoltage protection module. For example, for a vehicle-mounted air conditioner, the controller can further integrate a functional module for controlling a compressor and the like.

[0083] The utility model embodiment further discloses a vehicle-mounted air conditioner, and the vehicle-mounted air conditioner comprises the controller according to the preceding embodiments, wherein the sampling circuit 1 is coupled with the dc voltage power supply end of a fan.

[0084] In this embodiment of the invention, the vehicle air conditioner is a device used to regulate the temperature, humidity, and airflow inside a vehicle. It typically comprises a compressor, condenser, evaporator, throttling element, and load 5. Because the compressor and load 5 in the vehicle air conditioner consume additional power during operation, significant voltage fluctuations occur when the vehicle starts or stops, potentially causing overvoltage damage to the internal control components of the fan load 5. Therefore, if the overvoltage protection module is applied to the overvoltage protection of the load 5 in the vehicle air conditioner, the load 5 in the above embodiment can be the motor component of the fan. The voltage output terminal of the sampling circuit 1 is coupled to the DC voltage supply terminal of the fan motor to detect whether there is an overvoltage in the fan's operating voltage. This improves the reliability of the fan overvoltage protection and the operational stability of the fan.

[0085] This utility model embodiment also discloses a vehicle, which includes the vehicle air conditioner described in the above utility model embodiment.

[0086] In summary, this utility model discloses an overvoltage protection module, a controller, a vehicle air conditioner, and a vehicle. This utility model embodiment may include a sampling circuit 1, a voltage comparator 2, and a voltage conversion switch circuit 3. The sampling circuit 1 is coupled to the DC voltage supply terminal of the load 5 to detect the operating voltage of the load 5. The first input terminal of the voltage comparator 2 is coupled to the voltage output terminal of the sampling circuit 1. The voltage conversion switch circuit 3 is coupled between the second input terminal and the comparison output terminal of the voltage comparator 2. The voltage conversion switch circuit 3 is coupled to the load 5, and converts the reference voltage input to the second input terminal through the output level of the voltage comparator 2 to form dual-threshold overvoltage protection for the load 5. Thus, by setting two reference voltages, when the voltage is higher than the first reference voltage, the load 5 is controlled to be de-energized for overvoltage protection; when the voltage is lower than the second reference voltage, the load 5 is controlled to be energized for operation. Therefore, the overvoltage protection will only be deactivated when the detected voltage is lower than the second reference voltage, avoiding the problem of frequent start-stop of transistors caused by voltage fluctuations at the protection voltage threshold. This improves the reliability of the overvoltage protection of load 5 and the operational stability of load 5.

[0087] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0088] It will be readily apparent to those skilled in the art that any combination of the above embodiments is feasible. Therefore, any combination of the above embodiments is an implementation scheme of this utility model. However, due to space limitations, this specification will not describe them in detail here.

[0089] In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the application can be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been described in detail in order to not obscure the understanding of this description.

[0090] Similarly, it is to be understood that the mechanical features of the inventive aspects herein are sometimes illustrated in

[0091] Also, it is to be understood that the features of the dependent claims can be combined with those of the independent claims in any way deemed appropriate by the skilled addressee in the field of the application.

Claims

1. An overvoltage protection module, characterized in that, The overvoltage protection module includes: The sampling circuit (1) is coupled to the DC voltage power supply terminal of the load (5) to detect the operating voltage of the load (5); Voltage comparator (2), the first input terminal of the voltage comparator (2) is coupled to the voltage output terminal of the sampling circuit (1); A voltage conversion switch circuit (3) is coupled between the second input terminal and the comparison output terminal of the voltage comparator (2). The voltage conversion switch circuit (3) is coupled to the load (5). The reference voltage input at the second input terminal is converted by the output level of the voltage comparator (2) to form a dual threshold overvoltage protection for the load (5).

2. The overvoltage protection module according to claim 1, characterized in that, The voltage conversion switching circuit (3) includes: A first transistor (301) is coupled to the comparison output terminal of the voltage comparator (2) and the second terminal of the first transistor (301) is coupled to the load (5) so as to control the energizing state of the load (5) through the first transistor (301). The second transistor (302) has its first terminal coupled to the comparison output terminal of the voltage comparator (2), and its second terminal coupled to the second input terminal of the voltage comparator (2). A first feedback resistor (303) is connected at one end to the third terminal of the second transistor (302); The second feedback resistor (304) has one end coupled to the regulated power supply and the other end coupled to the second terminal of the second transistor (302); The third feedback resistor (305) has one end coupled to the other end of the first feedback resistor (303) and grounded, and the other end coupled to the second terminal of the second transistor (302).

3. The overvoltage protection module according to claim 2, characterized in that, The first transistor (301) is an NPN transistor, and the second transistor (302) is a PNP transistor. The first electrode of the first transistor (301) is the base, and the second electrode of the first transistor (301) is the collector. The first electrode of the second transistor (302) is the base, and the second electrode of the second transistor (302) is the emitter.

4. The overvoltage protection module according to claim 2, characterized in that, The first transistor (301) is a PNP transistor, and the second transistor (302) is an NPN transistor, wherein the first electrode of the first transistor (301) is the base, and the second electrode of the first transistor (301) is the collector; The first electrode of the second transistor (302) is the base, and the second electrode of the second transistor (302) is the collector.

5. The overvoltage protection module according to claim 2, characterized in that, The first transistor (301) is an N-type MOS transistor, and the second transistor (302) is a P-type MOS transistor, wherein the first electrode of the first transistor (301) is the gate, and the second electrode of the first transistor (301) is the drain; The first electrode of the second transistor (302) is the gate electrode, and the second electrode of the second transistor (302) is the source electrode.

6. The overvoltage protection module according to claim 2, characterized in that, The first transistor (301) is a P-type MOS transistor, and the second transistor (302) is an N-type MOS transistor, wherein the first electrode of the first transistor (301) is the gate, and the second electrode of the first transistor (301) is the source; The first electrode of the second transistor (302) is the gate electrode, and the second electrode of the second transistor (302) is the drain electrode.

7. The overvoltage protection module according to claim 2, characterized in that, The overvoltage protection module also includes a current-limiting resistor (4), which is coupled between the comparison output terminal of the voltage comparator (2) and the first terminal of the first transistor (301).

8. The overvoltage protection module according to claim 1, characterized in that, The sampling circuit (1) includes a first sampling resistor (101) and a second sampling resistor (102), wherein the first sampling resistor (101) and the second sampling resistor (102) are connected in series, and the connection point of the first sampling resistor (101) and the second sampling resistor (102) serves as the voltage output terminal of the sampling circuit (1). The end of the second sampling resistor (102) away from the first sampling resistor (101) is grounded, and the end of the first sampling resistor (101) away from the second sampling resistor (102) is coupled to the DC voltage power supply terminal of the load (5).

9. The overvoltage protection module according to claim 2, characterized in that, When at least two of the first feedback resistors (303) are provided, the at least two of the first feedback resistors (303) are connected in series; and / or, When at least two second feedback resistors (304) are provided, the at least two second feedback resistors (304) are connected in series; and / or, When at least two third feedback resistors (305) are provided, the at least two third feedback resistors (305) are connected in series.

10. A controller, characterized in that, The controller includes an overvoltage protection module as described in any one of claims 1-9.

11. A vehicle air conditioner, characterized in that, The vehicle air conditioner includes the controller as described in claim 10, wherein the sampling circuit (1) is coupled to the DC voltage power supply terminal of the fan.

12. A vehicle, characterized in that, The vehicle includes the vehicle air conditioner as described in claim 11.

Images