A high-voltage interlocking circuit and an electrical appliance

Abstract

The utility model discloses a kind of high-voltage interlock circuit and electrical equipment, the switching device in this circuit is connected between voltage source and ground terminal, the first end of switching device is connected to host computer and feeds back the on-off state of high-voltage connector to host computer. State sampling circuit is connected with the interlock input interface and interlock output interface of high-voltage connector respectively, and is configured to generate corresponding sampling signal according to the on-off state between interlock input interface and interlock output interface. Current adjustment circuit is connected with state sampling circuit, the second end of switching device and the control end of switching device respectively, and current adjustment circuit is configured to control the voltage of the second end of switching device equal to the voltage of sampling signal by adjusting the conduction degree of switching device, realize the interlock state detection and feedback of high-voltage connector, and the circuit sampling composition is simple and single terminal is carried out state feedback by host computer, and on the basis of reducing production cost, the interface resource of host computer is also saved.

Description

Technical Field

[0001] This utility model relates to the field of circuit design, and in particular to a high-voltage interlock circuit and electrical equipment. Background Technology

[0002] High-voltage interlock circuits are functional circuits used to detect the connection status of high-voltage connectors in high-voltage circuits. They can not only detect the connection status of high-voltage connectors, but also identify the types of faults that occur in high-voltage connectors, and are widely used in various industries.

[0003] Currently available high-voltage interlock circuits typically connect a high-side current source to the high-voltage interlock circuit to detect the voltage drop generated by the current flowing through each resistor, thereby determining the interlock status. However, this circuit design involves many components and is relatively complex, resulting in higher circuit costs. Utility Model Content

[0004] This invention provides a high-voltage interlock circuit and electrical equipment to reduce circuit complexity and production costs.

[0005] According to one aspect of the present invention, a high-voltage interlock circuit is provided, characterized in that it includes: a voltage source, a switching device, a state sampling circuit, and a current adjustment circuit;

[0006] The state sampling circuit is connected to the interlock input interface and the interlock output interface of the high-voltage connector respectively, and is configured to generate a corresponding sampling signal according to the on / off state between the interlock input interface and the interlock output interface;

[0007] The current adjustment circuit is connected to the state sampling circuit, the second terminal of the switching device, and the control terminal of the switching device, respectively. The current adjustment circuit is configured to adjust the conduction degree of the switching device according to the sampling signal and the voltage signal at the second terminal of the switching device.

[0008] The switching device is connected between the voltage source and the ground terminal. The first end of the switching device serves as the status feedback terminal of the high-voltage interlock circuit, which is connected to the host computer and feeds back the on / off status of the high-voltage connector to the host computer.

[0009] Optionally, the current adjustment circuit includes an operational amplifier, the positive input terminal of which is connected to the state sampling circuit to receive the sampling signal; the inverting input terminal of which is connected to the second terminal of the switching device; and the output terminal of which is connected to the control terminal of the switching device. The operational amplifier is configured to apply a corresponding control signal to the control terminal of the switching device based on the difference between the voltage at the second terminal of the switching device and the voltage of the sampling signal.

[0010] Optionally, the current adjustment circuit further includes a first resistor and a second resistor, wherein the first resistor is disposed between the output terminal of the operational amplifier and the control terminal of the switching device; and the second resistor is disposed between the inverting input terminal of the operational amplifier and the second terminal of the switching device.

[0011] Optionally, the operational amplifier is powered by the constant power supply of the circuit to which the high-voltage connector is applied.

[0012] Optionally, the supply voltage of the constant power supply is 12V or 24V.

[0013] Optionally, the state sampling circuit includes a third resistor, a fourth resistor, and a fifth resistor, which are connected in series between the voltage source and the ground terminal; the far-ground end of the fourth resistor serves as a first sampling terminal and is connected to the interlocked output interface; the near-ground end of the fourth resistor serves as a second sampling terminal and is connected to the interlocked input interface.

[0014] The far-ground terminal of the fourth resistor also serves as a sampling signal output terminal, which is connected to the current adjustment circuit.

[0015] Optionally, the high-voltage interlock circuit further includes a sixth resistor and a seventh resistor, wherein the sixth resistor is connected between the voltage source and the switching device, and the seventh resistor is connected between the switching device and the ground terminal.

[0016] Optionally, the supply voltage of the voltage source is 5V; the resistance values ​​of the third, fourth, fifth, sixth and seventh resistors are 120kΩ, 50kΩ, 30kΩ, 5kΩ and 10kΩ respectively.

[0017] Optionally, the switching device includes an N-type metal-oxide-semiconductor.

[0018] According to another aspect of the present invention, an electrical device is provided, which includes a high-voltage connector, a host computer, and the high-voltage interlock circuit described in the first aspect.

[0019] The high-voltage interlock circuit and electrical equipment provided in this embodiment include a voltage source, a switching device, a status sampling circuit, and a current adjustment circuit. The switching device is connected between the voltage source and the ground terminal. The first terminal of the switching device serves as the status feedback terminal of the high-voltage interlock circuit, connected to a host computer, and provides feedback on the on / off status of the high-voltage connector to the host computer. The status sampling circuit is connected to the interlock input interface and interlock output interface of the high-voltage connector, and is configured to generate corresponding sampling signals based on the on / off status between the interlock input interface and the interlock output interface. The current adjustment circuit is connected to the status sampling circuit, the second terminal of the switching device, and the control terminal of the switching device. The current adjustment circuit is configured to control the voltage at the second terminal of the switching device to equal the voltage of the sampling signal by adjusting the conduction degree of the switching device, thus realizing the detection and feedback of the interlock status of the high-voltage connector. This circuit has a simple sampling structure, with a single terminal providing status feedback to the host computer, reducing production costs and saving interface resources of the host computer.

[0020] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this utility model, nor is it intended to limit the scope of this utility model. Other features of this utility model will become readily apparent from the following description. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 A schematic diagram of a high-voltage interlock circuit provided for an embodiment of this utility model;

[0023] Figure 2 A schematic diagram of another high-voltage interlock circuit provided in this embodiment of the present utility model;

[0024] Figure 3 This is a schematic diagram of the composition of an electrical device provided in an embodiment of the present utility model. Detailed Implementation

[0025] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0026] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0027] To address the problems mentioned in the background art, this utility model proposes a high-voltage interlock circuit for detecting the interlock status of a high-voltage connector. Figure 1 A schematic diagram of a high-voltage interlock circuit provided in this embodiment of the present invention is shown below. Figure 1 The high-voltage interlock circuit 100 includes a voltage source 101, a switching device 102, a status sampling circuit 103, and a current adjustment circuit 104. The switching device 102 is connected between the voltage source 101 and the ground terminal GND. The first terminal of the switching device 102 serves as the status feedback terminal ADC_IN of the high-voltage interlock circuit 100, connected to a host computer and feeding back the on / off status of the high-voltage connector to the host computer. The status sampling circuit 103 is connected to the interlock input interface HVIL_IN and the interlock output interface HVIL_OUT of the high-voltage connector, and is configured to generate corresponding sampling signals based on the on / off status between the interlock input interface HVIL_IN and the interlock output interface HVIL_OUT. The current adjustment circuit 104 is connected to the state sampling circuit 103, the second terminal of the switching device 102, and the control terminal of the switching device 102, respectively. The current adjustment circuit 104 is configured to adjust the conduction degree of the switching device 102 according to the sampling signal and the voltage signal at the second terminal of the switching device 102, so as to control the voltage at the second terminal of the switching device 102 to tend to be equal to the voltage of the sampling signal.

[0028] Specifically, the state sampling circuit 103 refers to a sampling function circuit used to detect the on / off state between the interlock input interface HVIL_IN and the interlock output interface HVIL_OUT of the high-voltage connector. It can output a corresponding sampling signal according to the on / off state between the interlock input interface HVIL_IN and the interlock output interface HVIL_OUT. For example, the state sampling circuit 103 may include a sampling resistor connected between the interlock input interface HVIL_IN and the interlock output interface HVIL_OUT of the high-voltage connector. By connecting a low-voltage power supply to the sampling resistor, a corresponding voltage signal is generated across the sampling resistor. The sampling signal can be a voltage signal across the sampling resistor. The on / off state between the interlock input interface HVIL_IN and the interlock output interface HVIL_OUT can correspond to different voltage values ​​across the sampling resistor.

[0029] Voltage source 101 is a DC power supply with a preset voltage value. For example, voltage source 101 can provide a 5V voltage. Switching device 102 is a functional device that guides the adjustment of on-resistance and on-off state. It is connected between voltage source 101 and ground terminal GND. It can adjust its own state under the control of current adjustment circuit 104, thereby realizing the adjustment of the current flowing through it. For example, switching device 102 may include metal oxide semiconductor, such as N-type metal oxide semiconductor (also known as N-type MOS transistor).

[0030] The current adjustment circuit 104 is a functional circuit that controls the state of the switching device 102 based on the sampling signal output by the state sampling circuit 103. It can control the conduction degree of the switching device 102 by adjusting the signal connected to the control terminal of the switching device 102, thereby adjusting the current flowing through the switching device 102. For example, the current adjustment circuit 104 may include an operational amplifier. The sampling signal connected to the operational amplifier and the electrical signal at the second terminal of the switching device 102 are adjusted according to the difference between the two, thereby adjusting the conduction degree (or conduction resistance) of the switching device 102. The electrical signal output from the first terminal of the switching device 102 to the host computer changes accordingly with the degree of conduction of the switching device 102. The degree of conduction of the switching device 102 is related to the on / off state between the interlocked input interface HVIL_IN and the interlocked output interface HVIL_OUT. Based on this, the electrical signal output from the first terminal of the switching device 102 to the host computer changes accordingly with the on / off state between the interlocked input interface HVIL_IN and the interlocked output interface HVIL_OUT. The host computer can then determine the on / off state of the high-voltage connector based on the electrical signal of the status feedback terminal ADC_IN.

[0031] The high-voltage interlock circuit provided in this embodiment includes a voltage source, a switching device, a status sampling circuit, and a current adjustment circuit. The switching device is connected between the voltage source and the ground terminal. The first terminal of the switching device serves as the status feedback terminal of the high-voltage interlock circuit, connected to a host computer, and provides feedback on the on / off status of the high-voltage connector to the host computer. The status sampling circuit is connected to both the interlock input and interlock output interfaces of the high-voltage connector and is configured to generate corresponding sampling signals based on the on / off status between the interlock input and interlock output interfaces. The current adjustment circuit is connected to the status sampling circuit, the second terminal of the switching device, and the control terminal of the switching device. The current adjustment circuit is configured to adjust the conduction level of the switching device to control the voltage at the second terminal of the switching device to equal the voltage of the sampling signal, thus realizing the detection and feedback of the interlock status of the high-voltage connector. This circuit has a simple sampling structure, with a single terminal providing status feedback to the host computer, reducing production costs and saving interface resources of the host computer.

[0032] Optionally, Figure 2 This is a schematic diagram of another high-voltage interlock circuit provided in an embodiment of the present invention. Based on the foregoing embodiments, refer to... Figure 2 The current adjustment circuit 104 includes an operational amplifier 201. The positive input terminal of the operational amplifier 201 is connected to the state sampling circuit 103 to receive a sampling signal; the inverting input terminal of the operational amplifier 201 is connected to the second terminal of the switching device 102; the output terminal of the operational amplifier 201 is connected to the control terminal of the switching device 102; the operational amplifier 201 is configured to apply a corresponding control signal to the control terminal of the switching device 102 based on the difference between the voltage at the second terminal of the switching device 102 and the voltage of the sampling signal.

[0033] The current adjustment circuit 104 also includes a first resistor R1 and a second resistor R2. The first resistor R1 is located between the output terminal of the operational amplifier 201 and the control terminal of the switching device 102; the second resistor R2 is located between the inverting input terminal of the operational amplifier 201 and the second terminal of the switching device 102. The state sampling circuit 103 includes a third resistor R3, a fourth resistor R4, and a fifth resistor R5. The third resistor R3, the fourth resistor R4, and the fifth resistor R5 are connected in series between the voltage source 101 and the ground terminal GND. The far-ground end of the fourth resistor R4 serves as the first sampling terminal and is connected to the interlocked output interface HVIL_OUT; the near-ground end of the fourth resistor R4 serves as the second sampling terminal and is connected to the interlocked input interface HVIL_IN; the far-ground end of the fourth resistor R4 also serves as the sampling signal output terminal and is connected to the current adjustment circuit 104. The current adjustment circuit 104 also includes a sixth resistor R6 and a seventh resistor R7. The sixth resistor R6 is connected between the voltage source 101 and the switching device 102, and the seventh resistor R7 is connected between the switching device 102 and the ground terminal GND.

[0034] Specifically, in the state sampling circuit 103, the third resistor R3, the fourth resistor R4, and the fifth resistor R5 are connected in series between the voltage source 101 and the ground terminal GND. The two ends of the fourth resistor R4 are also connected to the interlock output interface HVIL_OUT and the interlock input interface HVIL_IN of the high-voltage connector, respectively. The series connection of the third resistor R3, the fourth resistor R4, and the fifth resistor R5 forms a low-voltage detection loop between the voltage source 101 and the ground terminal GND. When the high-voltage connector is in the ON state, the interlock output interface HVIL_OUT and the interlock input interface HVIL_IN are connected, and the fourth resistor R4 is short-circuited. Therefore, the far-ground terminal of the fourth resistor R4 serves as the sampling signal output terminal of the state sampling circuit 103, outputting the first voltage signal. Once the high-voltage connector is disconnected, the interlock output interface HVIL_OUT and the interlock input interface HVIL_IN are disconnected. In this case, the fourth resistor R4 participates in the voltage division in the low-voltage detection circuit, and the far-ground terminal of the fourth resistor R4 serves as the sampling signal output terminal of the state sampling circuit 103, outputting a second voltage signal. Since the voltage provided by the voltage source 101 is stable, the voltage at the far-ground terminal of the fourth resistor R4 after participating in the voltage division will be higher than the voltage at the far-ground terminal when the fourth resistor R4 is short-circuited. That is to say, the voltage value of the second voltage signal is greater than the voltage value of the first voltage signal. In the case of a short-ground fault in the high-voltage connector, a short circuit occurs between the interlock output interface HVIL_OUT and the ground terminal GND. In this case, the far-ground terminal of the fourth resistor R4 is also equivalent to grounded, and the far-ground terminal of the fourth resistor R4 serves as the sampling signal output terminal of the state sampling circuit 103, outputting a third voltage signal, where the voltage of the third voltage signal is 0V. In the event of a short power supply failure in the high-voltage connector, a short circuit occurs between the interlock output interface HVIL_OUT and the constant power supply KL30 of the circuit used by the high-voltage connector. In this case, the far-ground terminal of the fourth resistor R4 is also equivalent to being directly connected to the constant power supply KL30. Thus, the far-ground terminal of the fourth resistor R4 serves as the sampling signal output terminal of the status sampling circuit 103, outputting a fourth voltage signal. The voltage of the fourth voltage signal is equal to the voltage of the constant power supply KL30. For example, the voltage level of the constant power supply KL30 of the circuit used by the high-voltage connector can be 12V and / or 24V, then the fourth voltage signal can be equal to 12V or 24V.

[0035] The sixth resistor R6, the switching device 102, and the seventh resistor R7 are connected in series between the voltage source 101 and the ground terminal GND, forming a feedback loop between the voltage source 101 and the ground terminal GND. The first terminal of the switching device 102 serves as the status feedback terminal ADC_IN of the high-voltage interlock circuit 100, which is connected to the host computer and feeds back the on / off status of the high-voltage connector to the host computer. The second terminal of the switching device 102 is connected to the current adjustment circuit 104, providing a feedback signal to the current adjustment circuit 104, which is the voltage signal of the second terminal of the switching device 102.

[0036] Operational amplifier 201 is the main functional circuit of current adjustment circuit 104. It is powered by the constant power supply KL30 of the circuit used in the high-voltage connector, which can increase the withstand voltage level of the interlocked output interface HVIL_OUT. For example, the constant power supply KL30 can be 12V or 24V, compatible with different power system platforms. The positive input terminal of operational amplifier 201 in current adjustment circuit 104 is connected to the state sampling circuit 103, allowing it to receive a sampling signal. The inverting input terminal of operational amplifier 201 is connected to the second terminal of switching device 102 via the second resistor R2, providing the operational amplifier 201 with a feedback signal after voltage division by the second resistor R2. The output terminal of operational amplifier 201 is connected to the control terminal of switching device 102 via the first resistor R1, controlling the conduction level of switching device 102. Operational amplifier 201 can perform calculations based on the feedback signal after voltage division by the second resistor R2 and the sampling signal, outputting a voltage signal corresponding to the calculation result to control the conduction level of switching device 102, ensuring that the voltage level of the feedback signal is equal to or within the same range as the voltage level of the sampling signal. The conduction level of the switching device 102 varies depending on the state of the high-voltage connector, resulting in different voltage levels for the voltage signal output to the host computer from the status feedback terminal ADC_IN. The host computer can identify the state of the high-voltage connector based on the voltage level of the status feedback terminal ADC_IN.

[0037] For example, the supply voltage of the constant power supply KL30 is 12V, and the supply voltage of the voltage source 101 is V. CC The voltage is 5V. The resistance values ​​of the third resistor R3, fourth resistor R4, fifth resistor R5, sixth resistor R6, and seventh resistor R7 are 120kΩ, 50kΩ, 30kΩ, 5kΩ, and 10kΩ, respectively. When the high-voltage connector is working normally, the voltage of the interlocked output interface HVIL_OUT is within the normal range. The current adjustment circuit 104 can adjust the conduction degree of the switching device 102 according to the sampling signal and the voltage signal at the second terminal of the switching device 102, so as to control the voltage at the second terminal of the switching device 102 to remain equal to the voltage of the sampling signal. At this time, the relationship between the voltage at the second terminal of the switching device 102 and the voltage of the sampling signal is expressed by the first formula: ,in, The voltage at the second terminal of the switching device 102, The voltage of the sampled signal. The current in the feedback loop. It can be expressed by the second formula as follows Therefore, under normal operating conditions of the high-voltage connector, the voltage at the status feedback terminal ADC_IN is... This can be expressed by the third formula as follows: Conversely, the host computer uses the third formula and the voltage of the ADC_IN state feedback terminal to determine the input voltage. The voltage of the sampled signal can then be calculated. This allows us to determine the on / off state of the high-voltage connector.

[0038] Normal operation of the high-voltage connector includes normal conduction and normal shutdown. On the one hand, when the high-voltage connector is normally on, the interlocked output interface HVIL_OUT and the interlocked input interface HVIL_IN are connected, and the fourth resistor R4 is short-circuited, thus the voltage of the sampling signal output by the state sampling circuit 103 is... The voltage is 1V. Operational amplifier 201 adjusts the voltage of the sampled signal. and the voltage at the second terminal of the connected switching device 102 The conduction level of the switching device 102 is controlled so that the voltage at the second terminal of the switching device 102 is... equal to the voltage of the sampled signal This is equal to 1V. In this case, the voltage at the second terminal of the switching device 102 is... Substituting this into the third formula allows us to determine the voltage at the state feedback terminal ADC_IN. It equals 4.5V. On the other hand, when the high-voltage connector is normally off, the interlock output interface HVIL_OUT is disconnected from the interlock input interface HVIL_IN, and the fourth resistor R4 acts as a voltage divider in the low-voltage detection circuit, thus the voltage of the sampling signal output by the state sampling circuit 103 is... The voltage is 2V. Operational amplifier 201 operates based on the voltage of the sampled signal. and the voltage at the second terminal of the connected switching device 102 The conduction level of the switching device 102 is controlled so that the voltage at the second terminal of the switching device 102 is... equal to the voltage of the sampled signal This equals 12V. In this case, the voltage at the second terminal of the switching device 102 will... Substituting this into the third formula allows us to determine the voltage at the state feedback terminal ADC_IN. It equals 4V.

[0039] In the event of a high-voltage connector failure, the voltage of the interlocked output interface HVIL_OUT exceeds the normal range, and the aforementioned first, second, and third formulas are no longer fully applicable. The current adjustment circuit 104 can adjust the conduction level of the switching device 102 based on the sampling signal and the voltage signal at the second terminal of the switching device 102, thereby controlling the voltage at the second terminal of the switching device 102. The voltage that can approximate the sampled signal to the greatest extent possible .

[0040] High-voltage connector failures include short-to-ground faults and short-to-power-supply faults. In the event of a short-to-ground fault, a short circuit occurs between the interlocked output interface HVIL_OUT and the ground terminal GND. In this case, the far-ground terminal of the fourth resistor R4 is also effectively grounded, thus affecting the voltage of the sampled signal. The voltage is equal to 0V. Operational amplifier 201 is used to adjust the voltage at the second terminal of switching device 102. Voltage tending towards the sampled signal When the voltage is 0V, the resistance of the control switch 102 increases significantly, causing it to tend to disconnect. In this situation, due to the voltage divider effect in the feedback loop, the voltage at the state feedback terminal ADC_IN will... It will then tend to the supply voltage V of voltage source 101. CC That is, 5V. On the other hand, in the event of a short-circuit fault in the high-voltage connector, a short circuit occurs between the interlocked output interface HVIL_OUT and the constant power supply KL30. In this case, the far-ground terminal of the third resistor R3 is also equivalent to being connected to the constant power supply KL30, thus sampling the voltage of the signal. Equal to 12V. Operational amplifier 201 is used to adjust the voltage at the second terminal of switching device 102. Voltage tending towards the sampled signal That is, 12V, which will greatly reduce the resistance of the switching device 102 and make it approach 0. In this case, due to the voltage division effect in the feedback loop, the voltage at the state feedback terminal ADC_IN will... It will then tend to 3.3V.

[0041] In summary, if the host computer detects the voltage connected to the status feedback terminal ADC_IN... If the voltage is 4.5V, then the high-voltage connector is confirmed to be normally closed; if the host computer detects the voltage connected to the status feedback terminal ADC_IN... If the voltage is 4V, then the high-voltage connector is confirmed to be normally disconnected; if the host computer detects the voltage connected to the status feedback terminal ADC_IN... If the voltage is 5V, it can be determined that a short-to-ground fault has occurred in the high-voltage connector; if the host computer detects the voltage connected to the status feedback terminal ADC_IN... If the voltage is 3.3V, it can be determined that a short power supply fault has occurred in the high-voltage connector.

[0042] In the high-voltage interlock circuit provided in this embodiment, the current adjustment circuit includes an operational amplifier. The positive input terminal of the operational amplifier is connected to the state sampling circuit to receive the sampling signal; the inverting input terminal of the operational amplifier is connected to the second terminal of the switching device; the output terminal of the operational amplifier is connected to the control terminal of the switching device. The operational amplifier is configured to apply a corresponding control signal to the control terminal of the switching device based on the difference between the voltage at the second terminal of the switching device and the voltage of the sampling signal, thereby determining the state of the high-voltage connector. The operational amplifier is powered by a constant power supply, which increases the withstand voltage range of the interlock output interface. The constant power supply is compatible with both 12V and 24V power system platforms, broadening the application range of the circuit. The circuit composition and logic are simple, reducing production costs and the computational processing costs of the host computer.

[0043] This utility model embodiment also provides an electrical device. For example, the electrical device may include a new energy vehicle or other electrical devices designed with a high-voltage circuit. Figure 3 This is a schematic diagram of the composition of an electrical device provided in an embodiment of the present utility model. Based on the foregoing embodiments, refer to... Figure 3 The electrical equipment 300 includes a high-voltage connector 301, a host computer 302, and a high-voltage interlock circuit 100 in any of the aforementioned embodiments. The host computer 302 may include a microcontroller or a vehicle computer, or other devices with data conversion, analysis, and processing functions.

[0044] The high-voltage interlock circuit and electrical equipment provided in this embodiment include a voltage source, a switching device, a status sampling circuit, and a current adjustment circuit. The switching device is connected between the voltage source and the ground terminal. The first terminal of the switching device serves as the status feedback terminal of the high-voltage interlock circuit, connected to a host computer, and provides feedback on the on / off status of the high-voltage connector to the host computer. The status sampling circuit is connected to the interlock input interface and interlock output interface of the high-voltage connector, and is configured to generate corresponding sampling signals based on the on / off status between the interlock input interface and the interlock output interface. The current adjustment circuit is connected to the status sampling circuit, the second terminal of the switching device, and the control terminal of the switching device. The current adjustment circuit is configured to control the voltage at the second terminal of the switching device to equal the voltage of the sampling signal by adjusting the conduction degree of the switching device, thus realizing the detection and feedback of the interlock status of the high-voltage connector. This circuit has a simple sampling structure, with a single terminal providing status feedback to the host computer, reducing production costs and saving interface resources of the host computer.

[0045] It should be understood that the various forms of the process shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this utility model can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this utility model can be achieved, and this is not limited herein.

[0046] The specific embodiments described above do not constitute a limitation on the scope of protection of this utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A high-voltage interlock circuit, characterized in that, include: Voltage source, switching devices, status sampling circuit, and current regulation circuit; The state sampling circuit is connected to the interlock input interface and the interlock output interface of the high-voltage connector respectively, and is configured to generate a corresponding sampling signal according to the on / off state between the interlock input interface and the interlock output interface; The current adjustment circuit is connected to the state sampling circuit, the second terminal of the switching device, and the control terminal of the switching device, respectively. The current adjustment circuit is configured to adjust the conduction degree of the switching device according to the sampling signal and the voltage signal at the second terminal of the switching device. The switching device is connected between the voltage source and the ground terminal. The first end of the switching device serves as the status feedback terminal of the high-voltage interlock circuit, which is connected to the host computer and feeds back the on / off status of the high-voltage connector to the host computer.

2. The high-voltage interlock circuit according to claim 1, characterized in that, The current adjustment circuit includes: an operational amplifier, the positive input terminal of which is connected to the state sampling circuit to receive the sampling signal; the inverting input terminal of which is connected to the second terminal of the switching device; the output terminal of which is connected to the control terminal of the switching device; and the operational amplifier is configured to apply a corresponding control signal to the control terminal of the switching device based on the difference between the voltage at the second terminal of the switching device and the voltage of the sampling signal.

3. The high-voltage interlock circuit according to claim 2, characterized in that, The current adjustment circuit further includes a first resistor and a second resistor. The first resistor is disposed between the output terminal of the operational amplifier and the control terminal of the switching device; the second resistor is disposed between the inverting input terminal of the operational amplifier and the second terminal of the switching device.

4. The high-voltage interlock circuit according to claim 2, characterized in that, The operational amplifier is powered by the constant power supply of the circuit used by the high-voltage connector.

5. The high-voltage interlock circuit according to claim 4, characterized in that, The power supply voltage is 12V or 24V.

6. The high-voltage interlock circuit according to claim 1, characterized in that, The state sampling circuit includes a third resistor, a fourth resistor, and a fifth resistor, which are connected in series between the voltage source and the ground terminal; the far-ground end of the fourth resistor serves as a first sampling terminal and is connected to the interlocked output interface; the near-ground end of the fourth resistor serves as a second sampling terminal and is connected to the interlocked input interface. The far-ground terminal of the fourth resistor also serves as a sampling signal output terminal, which is connected to the current adjustment circuit.

7. The high-voltage interlock circuit according to claim 6, characterized in that, It also includes a sixth resistor and a seventh resistor, wherein the sixth resistor is connected between the voltage source and the switching device, and the seventh resistor is connected between the switching device and the ground terminal.

8. The high-voltage interlock circuit according to claim 7, characterized in that, The voltage source is supplied with a voltage of 5V; the resistance values ​​of the third, fourth, fifth, sixth, and seventh resistors are 120kΩ, 50kΩ, 30kΩ, 5kΩ, and 10kΩ, respectively.

9. The high-voltage interlock circuit according to claim 1, characterized in that, The switching device includes an N-type metal-oxide-semiconductor.

10. An electrical appliance, characterized in that, It includes a high-voltage connector, a host computer, and the high-voltage interlock circuit as described in any one of claims 1-9.

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