Insulation resistance monitoring circuit and method, air conditioner compressor and vehicle

Abstract

The invention relates to the technical field of resistance monitoring, and discloses an insulation resistance monitoring circuit and method, an air conditioner compressor and a vehicle, the circuit comprises a high-voltage power supply unit, an insulation detection unit connected with the high-voltage power supply unit and an external high-voltage power supply, and the insulation detection unit comprises a parallel resistance control subunit connected with the high-voltage power supply unit and connected with the high-voltage power supply unit. The control module is used for controlling the insulation resistor monitoring circuit to be in a parallel resistor connection state and a parallel resistor disconnection state; the resistance voltage dividing subunit is connected with the high-voltage power supply unit; the voltage sampling subunit is connected with the resistance voltage dividing subunit and is used for collecting a first voltage value in a parallel resistor connection state and a second voltage value in a parallel resistor disconnection state based on the resistance voltage dividing subunit; and the control chip is connected with the voltage sampling subunit and is used for monitoring the insulation resistance in the high-voltage power supply unit based on the first voltage value and the second voltage value. The cost of the insulation resistance monitoring circuit is reduced.

Description

Technical Field

[0001] This invention relates to the field of resistance monitoring technology, and in particular to an insulation resistance monitoring circuit, method, air conditioning compressor, and vehicle. Background Technology

[0002] As high-voltage power supply units are used more and more widely, users are also putting forward higher requirements for the insulation resistance monitoring circuits in high-voltage power supply units.

[0003] Traditional insulation resistance monitoring circuits employ separate sets of resistor divider circuits and isolation sampling circuits between the high-voltage positive terminal and the casing ground (equivalent ground of the vehicle body housing) of the high-voltage power supply unit, and between the high-voltage negative terminal and the casing ground. This allows for monitoring the insulation resistance between the high-voltage positive terminal and the casing ground, and between the high-voltage negative terminal and the casing ground, respectively, when the high-voltage power supply unit is connected to the high-voltage power supply unit. However, this type of insulation resistance monitoring circuit has significant drawbacks. It requires two separate sets of resistor divider circuits and isolation sampling circuits to achieve insulation resistance monitoring, resulting in higher costs.

[0004] The above content is only used to help understand the technical solution of this application and does not represent an admission that the above content is prior art. Summary of the Invention

[0005] The main objective of this invention is to provide an insulation resistance monitoring circuit, method, air conditioning compressor, and vehicle, aiming to solve the technical problem of high cost of insulation resistance monitoring circuits.

[0006] To achieve the above objectives, the present invention provides an insulation resistance monitoring circuit, which includes a high-voltage power supply unit and an insulation detection unit. The high-voltage power supply unit is connected to the insulation detection unit and an external high-voltage power supply. The insulation detection unit includes:

[0007] A parallel resistor control subunit is provided, which is connected to the first terminal and the second terminal of the high voltage power supply unit. The parallel resistor control subunit is used to control the insulation resistance monitoring circuit to be in a parallel resistor connected state and a parallel resistor disconnected state.

[0008] A voltage divider unit with a resistance, wherein the input terminal of the voltage divider unit is connected to the third terminal and the second terminal of the high-voltage power supply unit.

[0009] A voltage sampling subunit, the input terminal of which is connected to the output terminal of the resistor voltage divider subunit, is used to collect a first voltage value when the parallel resistor is connected and a second voltage value when the parallel resistor is disconnected based on the resistor voltage divider subunit;

[0010] A control chip is connected to the output terminal of the voltage sampling subunit. The control chip is used to monitor the insulation resistance in the high-voltage power supply unit based on the first voltage value and the second voltage value.

[0011] In one embodiment, the parallel resistor control subunit includes:

[0012] A control switch, the first end of which is connected to the first end of the high-voltage power supply unit;

[0013] A parallel resistor is provided, with its first end connected to the second end of the control switch and its second end connected to the second end of the high-voltage power supply unit.

[0014] In one embodiment, the resistive voltage divider subunit includes:

[0015] Multiple voltage divider resistors are connected in sequence. The first end of the first voltage divider resistor is connected to the third end of the high-voltage power supply unit, and the second end of the last voltage divider resistor is connected to the second end of the high-voltage power supply unit. The first end of the output resistor in the voltage divider resistor is connected to the input end of the voltage sampling subunit.

[0016] In one embodiment, the high-voltage power supply unit includes a high-voltage positive terminal, a high-voltage negative terminal, and a casing ground;

[0017] The high-voltage positive terminal serves as the first terminal of the high-voltage power supply unit, the high-voltage negative terminal serves as the third terminal of the high-voltage power supply unit, and the outer casing ground serves as the second terminal of the high-voltage power supply unit, or...

[0018] The high-voltage positive terminal serves as the third terminal of the high-voltage power supply unit, the high-voltage negative terminal serves as the first terminal of the high-voltage power supply unit, and the outer casing ground serves as the second terminal of the high-voltage power supply unit.

[0019] In one embodiment, the high-voltage power supply unit includes:

[0020] A first insulation resistor, wherein a first end of the first insulation resistor is connected to the positive terminal of the high voltage power supply and the high voltage positive terminal, and a second end of the first insulation resistor is connected to the ground of the casing;

[0021] The second insulation resistor has its second end connected to the negative terminal of the high-voltage power supply and the high-voltage negative terminal, and its first end connected to the ground of the casing.

[0022] In one embodiment, the control chip includes a high-voltage control chip and a low-voltage control chip;

[0023] When the control chip is the high-voltage control chip, the voltage sampling subunit includes an isolated sampling operational amplifier chip, wherein the input terminal of the isolated sampling operational amplifier chip is connected to the output terminal of the resistor voltage divider subunit, and the output terminal of the isolated sampling operational amplifier chip is connected to the high-voltage control chip;

[0024] When the control chip is the low-voltage control chip, the voltage sampling subunit includes a sampling operational amplifier chip, wherein the input terminal of the sampling operational amplifier chip is connected to the output terminal of the resistor voltage divider subunit, and the output terminal of the sampling operational amplifier chip is connected to the high-voltage control chip.

[0025] Furthermore, to achieve the above objectives, the present invention also provides a method for monitoring the insulation resistance of an air conditioner compressor. This method is applied to the aforementioned insulation resistance monitoring circuit and includes the following steps:

[0026] The voltage value collected by the voltage sampling subunit is obtained, wherein the voltage value includes a first voltage value when the insulation resistance monitoring circuit is in the state of parallel resistor connection and a second voltage value when the insulation resistance monitoring circuit is in the state of parallel resistor disconnection;

[0027] The insulation resistance in the high-voltage power supply unit is monitored based on the first voltage value and the second voltage value.

[0028] In one embodiment, the step of monitoring the insulation resistance in the high-voltage power supply unit based on the first voltage value and the second voltage value includes:

[0029] Determine the preset sampling ratio coefficient, the total resistance value of the resistor voltage divider subunit, the parallel resistance value of the parallel resistor in the parallel resistor control subunit, and the voltage value of the high voltage power supply;

[0030] A first current equation is established based on the first voltage value, the sampling ratio coefficient, the total resistance value, the parallel resistance value, and the voltage value;

[0031] A second current equation is established based on the second voltage value, the sampling ratio coefficient, the total resistance value, and the voltage value. The first current equation and the second current equation are both current equations established about the resistance values ​​of the first insulation resistance and the second insulation resistance in the high-voltage power supply unit.

[0032] The first resistance value of the first insulation resistor and the second resistance value of the second insulation resistor are determined based on the first current equation and the second current equation.

[0033] In addition, to achieve the above objectives, the present invention also provides an air conditioning compressor, which includes a controller, a motor and a compression unit, wherein the controller is provided with an insulation resistance monitoring circuit;

[0034] The controller is connected to the motor, and the motor is connected to the compression unit;

[0035] The controller is used to perform the steps of the insulation resistance monitoring method described above.

[0036] This application also provides a vehicle, the vehicle comprising:

[0037] An air conditioning compressor, which is also used to perform the steps of the above-described insulation resistance monitoring method.

[0038] This invention provides an insulation resistance monitoring circuit, which includes a high-voltage power supply unit and an insulation detection unit. The high-voltage power supply unit is connected to the insulation detection unit and an external high-voltage power supply. The insulation detection unit includes: a parallel resistor control subunit, connected to a first terminal and a second terminal of the high-voltage power supply unit, used to control the insulation resistance monitoring circuit to be in a parallel resistor connected state and a parallel resistor disconnected state; a resistor voltage divider subunit, whose input terminal is connected to a third terminal and a second terminal of the high-voltage power supply unit; a voltage sampling subunit, whose input terminal is connected to the output terminal of the resistor voltage divider subunit, used to collect a first voltage value in the parallel resistor connected state and a second voltage value in the parallel resistor disconnected state based on the resistor voltage divider subunit; and a control chip, connected to the output terminal of the voltage sampling subunit, used to monitor the insulation resistance in the high-voltage power supply unit based on the first voltage value and the second voltage value.

[0039] The insulation resistance monitoring circuit is controlled to be in the parallel resistance connected state and the parallel resistance disconnected state by the parallel resistance control subunit. Then, the voltage sampling subunit collects the first voltage value in the parallel resistance connected state and the second voltage value in the parallel resistance disconnected state. Finally, the insulation resistance in the high voltage power supply unit can be monitored based on the first voltage value and the second voltage value. This avoids the need for separate resistor divider circuits and isolation sampling circuits between the high-voltage positive terminal and the casing ground, and between the high-voltage negative terminal and the casing ground, as required in existing technologies for insulation resistance monitoring. This insulation resistance monitoring circuit monitors resistance by collecting the first voltage value when the parallel resistor is connected and the second voltage value when the parallel resistor is disconnected, thus achieving a new method of insulation resistance monitoring. Furthermore, by connecting the resistor divider subunit to the third and second terminals of the high-voltage power supply unit, and connecting the input terminal of the voltage sampling subunit to the output terminal of the resistor divider subunit, while the parallel resistor control subunit is connected to the first and second terminals of the high-voltage power supply unit, two sets of resistor divider circuits and isolation sampling circuits are not required. Ultimately, the insulation resistance in the high-voltage power supply unit can be monitored based on the first and second voltage values, thereby reducing the cost of the insulation resistance monitoring circuit. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0041] Figure 1 This is a schematic diagram of one module of the insulation resistance monitoring circuit of this application;

[0042] Figure 2 This is a schematic diagram of one module of an existing insulation resistance monitoring circuit;

[0043] Figure 3 This is a schematic diagram of an external connection for an existing insulation resistance monitoring circuit;

[0044] Figure 4 This is a schematic diagram of the high-voltage acquisition in the insulation resistance monitoring circuit of this application;

[0045] Figure 5 This is a circuit connection diagram of the first embodiment of the insulation resistance monitoring circuit of this application;

[0046] Figure 6 This is a circuit connection diagram of the second embodiment of the insulation resistance monitoring circuit of this application;

[0047] Figure 7 This is a circuit connection diagram of the third embodiment of the insulation resistance monitoring circuit of this application;

[0048] Figure 8 This is a circuit connection diagram of the fourth embodiment of the insulation resistance monitoring circuit of this application;

[0049] Figure 9 This is a schematic diagram of the circuit connection of the voltage divider subunit in the insulation resistance monitoring circuit of this application;

[0050] Figure 10 This is an equivalent schematic diagram of the insulation resistance monitoring circuit of this application;

[0051] Figure 11 This is another equivalent schematic diagram of the insulation resistance monitoring circuit of this application;

[0052] Figure 12 This is a schematic diagram of the structure of an air conditioning compressor in the hardware operating environment involved in the embodiments of the present invention;

[0053] Figure 13 This is a flowchart illustrating the first embodiment of the insulation resistance monitoring method of the present invention;

[0054] Figure 14 This is a schematic diagram illustrating the implementation process of the insulation resistance monitoring method of the present invention;

[0055] Figure 15 This is a schematic diagram of the air conditioner compressor module of the present invention.

[0056] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings.

[0057] Explanation of icon numbers:

[0058] 200. High-voltage power supply; 20. Insulation detection unit; 21. Parallel resistor control subunit; 22. Resistor voltage divider subunit; 23. Voltage sampling subunit; 24. Control chip; 10. High-voltage power supply unit; S. High-voltage switch; U DC High-voltage power supply; R P First insulation resistance; R N 1. Second insulation resistance; S1. Control switch; R0. Parallel resistor; RX. Output resistor; R1. Voltage divider resistor. Detailed Implementation

[0059] It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.

[0060] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.

[0061] A commonly used insulation resistance monitoring circuit consists of a resistor divider circuit and an isolation sampling circuit installed between the high-voltage positive terminal and the casing ground, and between the high-voltage negative terminal and the casing ground, respectively. This allows for monitoring of the insulation resistance between the high-voltage positive terminal and the casing ground, and between the high-voltage negative terminal and the casing ground, when the high-voltage power supply is connected to the high-voltage power supply unit. (Refer to...) Figure 2 , Figure 2 This is a schematic diagram of the framework of an existing insulation resistance monitoring circuit, where R P R N These are the insulation resistances of the high-voltage positive and negative terminals to the chassis (body), respectively. By controlling the opening and closing of the two high-voltage switches S, and sampling and calculating the voltages VS1 and VS2 under various switching states, the insulation resistance R to be measured can be deduced. P and R N The resistance values ​​are used to monitor insulation resistance, where VS1 and VS2 are the voltage values ​​collected by the isolation sampling circuits when the two insulation resistors are connected individually. However, the above solution requires setting up a set of resistor voltage divider circuits and isolation sampling circuits separately between the high-voltage positive terminal and the casing ground, and between the high-voltage negative terminal and the casing ground, to achieve insulation resistance monitoring. This results in a significant increase in the required circuit area and cost due to the need to design two sets of resistor voltage divider circuits and isolation sampling circuits to detect the insulation resistance, which is detrimental to the design and use cost of high-voltage components such as air conditioning compressors.

[0062] Therefore, based on the shortcomings of the above insulation resistance monitoring circuit methods, the insulation resistance monitoring circuit of this application is proposed. The main solution of the embodiment of this application is: the insulation resistance monitoring circuit is controlled to be in the parallel resistance connected state and the parallel resistance disconnected state by the parallel resistance control subunit, and then the first voltage value in the parallel resistance connected state and the second voltage value in the parallel resistance disconnected state are collected by the voltage sampling subunit. Finally, the insulation resistance in the high voltage power supply unit can be monitored based on the first voltage value and the second voltage value. This avoids the need for separate resistor divider circuits and isolation sampling circuits between the high-voltage positive terminal and the casing ground, and between the high-voltage negative terminal and the casing ground, as required in existing technologies for insulation resistance monitoring. This insulation resistance monitoring circuit monitors resistance by collecting the first voltage value when the parallel resistor is connected and the second voltage value when the parallel resistor is disconnected, thus achieving a new method of insulation resistance monitoring. Furthermore, by connecting the resistor divider subunit to the third and second terminals of the high-voltage power supply unit, and connecting the input terminal of the voltage sampling subunit to the output terminal of the resistor divider subunit, while the parallel resistor control subunit is connected to the first and second terminals of the high-voltage power supply unit, two sets of resistor divider circuits and isolation sampling circuits are not required. Ultimately, the insulation resistance in the high-voltage power supply unit can be monitored based on the first and second voltage values, thereby reducing the cost of the insulation resistance monitoring circuit.

[0063] Based on this, embodiments of this application provide a control device for a parallel power module, referring to... Figure 1 , Figure 1 This is a schematic diagram of one module of the insulation resistance monitoring circuit of this application.

[0064] Reference Figure 1 This application provides an insulation resistance monitoring circuit, including a high-voltage power supply unit 10 and an insulation detection unit 20. The high-voltage power supply unit 10 is connected to the insulation detection unit 20 and an external high-voltage power supply 200. The insulation detection unit 20 includes:

[0065] Parallel resistor control subunit 21 is connected to the first end and the second end of the high voltage power supply unit 10. Parallel resistor control subunit 21 is used to control the insulation resistance monitoring circuit to be in the parallel resistor connected state and the parallel resistor disconnected state.

[0066] The input terminal of the voltage divider unit 22 is connected to the third terminal and the second terminal of the high voltage power supply unit 10.

[0067] Voltage sampling subunit 23, the input terminal of voltage sampling subunit 23 is connected to the output terminal of resistor voltage divider subunit 22, voltage sampling subunit 23 is used to collect the first voltage value when the parallel resistor is connected and the second voltage value when the parallel resistor is disconnected based on resistor voltage divider subunit 22;

[0068] Control chip 24 is connected to the output terminal of voltage sampling subunit 23. Control chip 24 is used to monitor the insulation resistance in high voltage power supply unit 10 based on first voltage value and second voltage value.

[0069] For example, refer to Figure 3 , Figure 3 This is a schematic diagram of the external connection of an existing insulation resistance monitoring circuit. The entire circuit can be divided into high-voltage and low-voltage circuits. The low-voltage circuit supplies power to various components and units, such as control unit 1, the isolation communication unit, and control unit 2 and the drive circuit in the high-voltage circuit. The high-voltage power supply refers to the power supply to the inverter, which in turn drives the motor, such as the voltage of a three-phase motor. The high-voltage and low-voltage circuits are separated by isolation devices. Taking an air conditioning compressor (hereinafter referred to as: compressor) as an example, the compressor has both high-voltage and low-voltage power supplies. A conventional circuit architecture is as follows: Figure 3 As shown, the compressor's low-pressure negative terminal, the compressor casing, and the vehicle body are connected together (usually divided into near-end grounding and far-end grounding; near-end grounding involves short-circuiting the compressor's low-pressure negative terminal and the casing inside the compressor, while far-end grounding involves short-circuiting the low-pressure negative terminal and the vehicle body outside the compressor). Further details can be found in [reference needed]. Figure 4 , Figure 4 This is a schematic diagram of the high voltage acquisition in the insulation resistance monitoring circuit of this application. The voltage value of the high voltage power supply can be stored in the control unit 2 in the high voltage circuit through the internal resistor voltage divider circuit and sampling circuit for subsequent retrieval. It is worth noting that the above is only an external connection diagram of the insulation resistance monitoring circuit, and other connection diagrams are also possible. The external connection of the insulation resistance monitoring circuit is not limited here.

[0070] In this embodiment, to achieve insulation resistance monitoring using fewer resistor voltage divider circuits and isolation sampling circuits, an insulation resistance monitoring circuit of this embodiment is proposed. This insulation resistance monitoring circuit can achieve insulation resistance monitoring using only one set of resistor voltage divider subunit 22, voltage sampling subunit 23 and parallel resistor control subunit 21, thereby reducing the cost and area occupied by the insulation resistance monitoring circuit. The monitoring principle of the entire insulation resistance monitoring circuit is as follows: The parallel resistor control subunit 21 connects the first and second terminals of the high-voltage power supply unit 10, thereby controlling the insulation resistance monitoring circuit to be in a parallel resistor connected state and a parallel resistor disconnected state. In other words, the parallel resistor control subunit 21 can control the entire insulation resistance monitoring circuit to be in two different connection states. The parallel resistor connected state refers to the state where the parallel resistor in the parallel resistor control subunit 21 is connected to the insulation resistance monitoring circuit, and the parallel resistor disconnected state refers to the state where the parallel resistor in the parallel resistor control subunit 21 is disconnected from the insulation resistance monitoring circuit. At this time, the first voltage value and the second voltage value can be collected based on the voltage sampling subunit 23 under these two different states. Finally, based on the two voltage values, two sets of equations can be established for the two states, and by solving the unknowns in the equations, the resistance value of the insulation resistance in the high-voltage power supply unit 10 can be determined. It is worth noting that the insulation resistance in the high-voltage power supply unit 10 is the unknown to be solved; other parameters in the circuit can be determined based on sampling or actual settings, such as the first voltage value, the second voltage value, and the resistance value of the parallel resistor. Furthermore, the insulation resistance monitoring circuit can be controlled to be in the parallel resistance connected state and the parallel resistance disconnected state based solely on the parallel resistance control subunit 21. Then, the voltage sampling subunit 23 collects the first voltage value in the parallel resistance connected state and the second voltage value in the parallel resistance disconnected state. Finally, two equations can be established based on the first voltage value and the second voltage value to determine whether the insulation resistance in the high-voltage power supply unit 10 (taking the case where there are only two insulation resistances in a conventional high-voltage power supply unit 10 as an example) is within the set range, so as to reduce the cost of the insulation resistance monitoring circuit.

[0071] In this embodiment, an insulation resistance monitoring circuit is provided. The circuit includes a high-voltage power supply unit and an insulation detection unit. The high-voltage power supply unit is connected to the insulation detection unit and an external high-voltage power supply. The insulation detection unit includes: a parallel resistor control subunit connected to a first terminal and a second terminal of the high-voltage power supply unit, used to control the insulation resistance monitoring circuit to be in a parallel resistor connected state and a parallel resistor disconnected state; a voltage divider subunit, its input terminal connected to a third terminal and a second terminal of the high-voltage power supply unit; a voltage sampling subunit, its input terminal connected to the output terminal of the voltage divider subunit, used to acquire a first voltage value in the parallel resistor connected state and a second voltage value in the parallel resistor disconnected state based on the voltage divider subunit; and a control chip connected to the output terminal of the voltage sampling subunit, used to monitor the insulation resistance in the high-voltage power supply unit based on the first voltage value and the second voltage value. The insulation resistance monitoring circuit is controlled to be in the parallel resistance connected state and the parallel resistance disconnected state by the parallel resistance control subunit. Then, the voltage sampling subunit collects the first voltage value in the parallel resistance connected state and the second voltage value in the parallel resistance disconnected state. Finally, the insulation resistance in the high voltage power supply unit can be monitored based on the first voltage value and the second voltage value. This avoids the need for separate resistor divider circuits and isolation sampling circuits between the high-voltage positive terminal and the casing ground, and between the high-voltage negative terminal and the casing ground, as required in existing technologies for insulation resistance monitoring. This insulation resistance monitoring circuit monitors resistance by collecting the first voltage value when the parallel resistor is connected and the second voltage value when the parallel resistor is disconnected, thus achieving a new method of insulation resistance monitoring. Furthermore, by connecting the resistor divider subunit to the third and second terminals of the high-voltage power supply unit, and connecting the input terminal of the voltage sampling subunit to the output terminal of the resistor divider subunit, while the parallel resistor control subunit is connected to the first and second terminals of the high-voltage power supply unit, two sets of resistor divider circuits and isolation sampling circuits are not required. Ultimately, the insulation resistance in the high-voltage power supply unit can be monitored based on the first and second voltage values, thereby reducing the cost of the insulation resistance monitoring circuit.

[0072] Furthermore, based on the first embodiment of the insulation resistance monitoring circuit, a second embodiment of this application is proposed, with reference to... Figure 5 , Figure 5 This is a circuit connection diagram of the first embodiment of the insulation resistance monitoring circuit of this application. The parallel resistance control subunit 21 includes:

[0073] Control switch S1, the first end of control switch S1 is connected to the first end of high voltage power supply unit 10;

[0074] A parallel resistor R0 is connected. The first end of the parallel resistor R0 is connected to the second end of the control switch S1, and the second end of the parallel resistor R0 is connected to the second end of the high-voltage power supply unit 10.

[0075] For example, the parallel resistor control subunit 21 includes a control switch S1 and a parallel resistor R0. By controlling the control switch S1, the parallel resistor R0 can be connected to or disconnected from the insulation resistance monitoring circuit. In this case, the voltage values ​​under both conditions can be collected by the resistor voltage divider subunit 22 and the voltage sampling subunit 23. Based on these two voltage values, a relationship between the insulation resistance and the parallel resistor R0 can be established, allowing the determination of the two insulation resistance values. This embodiment replaces the function of a resistor voltage divider circuit and an isolation sampling circuit with the control switch S1 and the parallel resistor R0, thus achieving insulation resistance monitoring with low cost and small footprint. It is worth noting that the control switch S1 can use a transistor or switching device to improve intelligence, and can then be connected to the control chip 24 for intelligent switching control based on the control chip 24.

[0076] In one embodiment, the control chip 24 includes a high-voltage control chip and a low-voltage control chip;

[0077] When the control chip 24 is a high-voltage control chip, the voltage sampling subunit 23 includes an isolated sampling operational amplifier chip, wherein the input terminal of the isolated sampling operational amplifier chip is connected to the output terminal of the resistor voltage divider subunit 22, and the output terminal of the isolated sampling operational amplifier chip is connected to the high-voltage control chip.

[0078] When the control chip 24 is a low-voltage control chip, the voltage sampling subunit 23 includes a sampling operational amplifier chip, wherein the input terminal of the sampling operational amplifier chip is connected to the output terminal of the resistor voltage divider subunit 22, and the output terminal of the sampling operational amplifier chip is connected to the high-voltage control chip.

[0079] In one embodiment, reference may be made to Figure 6 , Figure 6 This is a circuit connection diagram of the second embodiment of the insulation resistance monitoring circuit of this application. Because the control unit 1 and the resistor divider subunit 22 in the low-voltage circuit share a common ground (the triangle represents the low-voltage reference ground, the mountain-shaped symbol represents the chassis, and the three short horizontal lines represent the high-voltage reference ground), if the control chip 24 is located within the control unit 1, the commonly used voltage sampling subunit 23 can be used directly for sampling. Figure 6The high-voltage reference ground is not shared with the resistor voltage divider unit 22. Therefore, when the control unit 1 is not present in the low-voltage circuit, and the control unit 2 in the high-voltage circuit is used directly, an isolated voltage sampling subunit 23 is required. The voltage sampling subunit 23 can be a commonly used sampling operational amplifier chip or other sampling instruments. Furthermore, referring to... Figure 7 , Figure 7 This is a circuit connection diagram of the third embodiment of the insulation resistance monitoring circuit of this application. After the voltage divider subunit 22, another voltage divider subunit 22 can be connected in parallel to collect two voltage values ​​to ensure the accuracy of the data acquisition. In one embodiment, refer to... Figure 8 , Figure 8 This is a circuit connection diagram of the fourth embodiment of the insulation resistance monitoring circuit of this application. The parallel resistor control subunit 21 can also be directly a resistor voltage divider subunit 22. However, in this case, only one voltage sampling subunit 23 is needed to realize insulation resistance monitoring, thereby reducing the cost of the entire insulation resistance monitoring circuit. It is worth noting that the parallel resistor control subunit 21 can also be other resistor devices, which are not limited here.

[0080] In one embodiment, reference is made to Figure 9 , Figure 9 This is a circuit connection diagram of the voltage divider subunit in the insulation resistance monitoring circuit of this application. The voltage divider subunit 22 includes:

[0081] Multiple voltage divider resistors R1 are connected in sequence. The first end of the first voltage divider resistor R1 is connected to the third end of the high voltage power supply unit 10, and the second end of the last voltage divider resistor R1 is connected to the second end of the high voltage power supply unit 10. The first end of the output resistor RX in the voltage divider resistor R1 is connected to the input end of the voltage sampling subunit 23.

[0082] In this embodiment, the voltage divider subunit 22 includes multiple voltage divider resistors R1 connected in series. One of the voltage divider resistors R1 is an output resistor RX. The first end of the output resistor RX is connected to the input terminal of the voltage sampling subunit 23 to output the sampled voltage to the voltage sampling subunit 23. The function of the voltage divider subunit 22 is to prevent the output voltage from being too large and exceeding the voltage of the voltage sampling subunit 23. If the voltage division ratio of the entire voltage divider subunit 22 is set to M, it ensures that the sampled output voltage VN does not exceed the upper limit of the voltage allowed by the voltage sampling subunit 23. It is worth noting that the sampling capability of the voltage sampling subunit 23 can also be changed to directly sample the voltage of the entire voltage divider subunit 22. If the upper limit of the voltage allowed by the voltage sampling subunit 23 is VM, to ensure that VM≥VN, consider the most extreme case: the insulation resistance of the high-voltage negative electrode is zero, i.e., R... N =0, at this time, VN = M*V DCTherefore, it is only necessary to ensure that VM ≥ M * V DC That is, select M≥V DC By using / VM, the output voltage VN can be guaranteed to not exceed the upper limit of the sampling circuit's allowed voltage, thus ensuring the accuracy of the data acquisition.

[0083] In one embodiment, appropriate values ​​should be selected for the voltage divider resistor R1 and the parallel resistor R0 in the voltage divider subunit. In practice, values ​​related to the first insulation resistance R can be selected. P Second insulation resistance R N Resistors with resistance values ​​of similar order of magnitude should be used. Furthermore, the voltage ratings of the voltage divider resistor R1 and the parallel resistor R0 in the voltage divider subunit must meet the system design requirements. To improve the voltage rating, multiple resistors can be connected in series, and resistor packages with larger lead pitch should be selected. The selection of the control switch S1 requires attention to choosing a sufficiently high voltage rating; since the parallel resistor R0 is usually selected with a large resistance value, the branch current is very small, and the switching speed and current carrying capacity of the switch are not particularly demanding. Alternatively, a microcontroller with A / D sampling function can be selected as the control chip 24, which can simultaneously cover the functions of the sampling circuit and the control unit 1.

[0084] Furthermore, based on the first and / or second embodiments of the insulation resistance monitoring circuit, a third embodiment of this application is proposed, wherein the high-voltage power supply unit 10 includes a high-voltage positive terminal, a high-voltage negative terminal, and a housing ground;

[0085] The high-voltage positive terminal serves as the first terminal of the high-voltage power supply unit, the high-voltage negative terminal serves as the third terminal of the high-voltage power supply unit, and the outer casing ground serves as the second terminal of the high-voltage power supply unit, or...

[0086] The high-voltage positive terminal serves as the third terminal of the high-voltage power supply unit, the high-voltage negative terminal serves as the first terminal of the high-voltage power supply unit, and the outer casing ground serves as the second terminal of the high-voltage power supply unit.

[0087] Furthermore, the high-voltage power supply unit 10 includes:

[0088] First insulation resistance R P First insulation resistance R P The first terminal is connected to the positive terminal and the high voltage positive terminal of the high voltage power supply 200, and the first insulation resistance R P The second end is connected to the outer casing;

[0089] Second insulation resistance R N Second insulation resistance R N The second terminal is connected to the negative terminal and the high-voltage negative terminal of the high-voltage power supply 200, and the second insulation resistance R is described. N The first end is connected to the outer shell.

[0090] In this embodiment, the high-voltage power supply unit 10 includes a high-voltage positive terminal, a high-voltage negative terminal, and a casing ground. That is, the parallel resistor control subunit 21 and the resistor voltage divider subunit 22 can be arbitrarily connected separately between the high-voltage positive terminal and the casing ground, and between the high-voltage negative terminal and the casing ground. However, when the resistor voltage divider subunit 22 is between the high-voltage negative terminal and the casing ground, an isolation device is required to collect the voltage because the voltage value is negative at this time. On one hand, referring to... Figure 10 , Figure 10 This is an equivalent schematic diagram of the insulation resistance monitoring circuit of this application. Based on the composition of the high-voltage power supply unit 10 and the control state of the parallel resistor control subunit 21, the following can be obtained when the parallel resistor R0 is not connected to the circuit: Figure 10 The equivalent circuit, on the other hand, refers to Figure 11 , Figure 11 This is another equivalent schematic diagram of the insulation resistance monitoring circuit of this application. Based on the composition of the high-voltage power supply unit 10 and the control state of the parallel resistor control subunit 21, when the parallel resistor R0 is connected to the circuit, the following can be obtained: Figure 11 The equivalent circuit is shown. In this circuit, VDC (high voltage), R1 (total resistance of the voltage divider unit), R0 (parallel resistance), VS1 (sampled value of parallel resistor R0 when not connected to the circuit), and VS11 (sampled value of parallel resistor R0 when connected to the circuit) are known. Kirchhoff's current law (node ​​current method) is then used to... Figure 10 and Figure 11 To establish the current relationship, the following equation can be derived:

[0091]

[0092] Simplifying, we get:

[0093]

[0094] Solving the equations on the right side, we get:

[0095]

[0096] Substituting into equation (2), we get:

[0097]

[0098] Finally, the first insulation resistance R is obtained. P Second insulation resistance R N The insulation resistance is monitored by determining the resistance values ​​RP and RN based on preset values ​​to determine whether RP and RN meet the requirements. Furthermore, when insulation failure occurs in high-voltage vehicle components, the insulation resistance monitoring circuit can quickly and cost-effectively identify the fault and send the information to the vehicle controller via a communication circuit to control the high-voltage power supply and ensure power supply safety.

[0099] In yet another embodiment, reference is made to... Figure 12 , Figure 12 This is a schematic diagram of the structure of an air conditioning compressor in the hardware operating environment involved in the embodiments of the present invention.

[0100] like Figure 12 As shown, the air conditioner compressor may include: a processor 0003, such as a central processing unit (CPU), a communication bus 0001, an acquisition interface 0002, a processing interface 0004, and a memory 0005. The communication bus 0001 is used to enable communication between these components. The acquisition interface 0002 may include an information acquisition device or acquisition unit, such as a computer; optionally, the acquisition interface 0002 may also include a standard wired interface or a wireless interface. The processing interface 0004 may optionally include a standard wired interface or a wireless interface. The memory 0005 may be high-speed random access memory (RAM) or stable non-volatile memory (NVM), such as a disk storage device. Optionally, the memory 0005 may also be a storage device independent of the aforementioned processor 0003.

[0101] Those skilled in the art will understand that Figure 12 The structure shown does not constitute a limitation on the air conditioning compressor and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0102] like Figure 12 As shown, the memory 0005, which serves as a computer storage medium, may include an operating system, an acquisition interface module, a processing interface module, and an insulation resistance monitoring circuit program executed by the air conditioning compressor.

[0103] exist Figure 12 In the air conditioner compressor shown, the communication bus 0001 is mainly used to realize the connection and communication between components; the acquisition interface 0002 is mainly used to connect to the backend server and communicate with the backend server; the processing interface 0004 is mainly used to connect to the deployment end (user end) and communicate with the deployment end; the processor 0003 and the memory 0005 in the air conditioner compressor of the present invention can be set in the air conditioner compressor. The air conditioner compressor calls the insulation resistance monitoring circuit program stored in the memory 0005 through the processor 0003 and executes the insulation resistance monitoring circuit provided in the embodiment of the present invention.

[0104] Based on the above hardware structure, an embodiment of the insulation resistance monitoring method of the present invention is proposed.

[0105] In one embodiment of the present invention, such as Figure 13 As shown, Figure 13 This is a flowchart illustrating a first embodiment of the insulation resistance monitoring method of the present invention. The insulation resistance monitoring method is applied to the above-mentioned insulation resistance monitoring circuit, and the insulation resistance monitoring method includes:

[0106] Step S10: Obtain the voltage value collected by the voltage sampling subunit, wherein the voltage value includes a first voltage value when the insulation resistance monitoring circuit is in the parallel resistor connection state and a second voltage value when the insulation resistance monitoring circuit is in the parallel resistor disconnect state.

[0107] In this embodiment, during insulation resistance monitoring, the voltage sampling subunit in the insulation resistance monitoring circuit collects voltage values ​​under different states. These voltage values ​​include a first voltage value when the insulation resistance monitoring circuit is in a parallel resistor connected state and a second voltage value when the parallel resistor is disconnected. Specifically, the parallel resistor control subunit controls the insulation resistance monitoring circuit to be in a parallel resistor connected state (i.e., the parallel resistor in the control subunit is connected to the insulation resistance monitoring circuit) and to be in a parallel resistor disconnected state (i.e., the parallel resistor in the control subunit is disconnected from the insulation resistance monitoring circuit). After voltage division by the resistor voltage divider subunit, the voltage sampling subunit samples the first voltage value in the parallel resistor connected state and the second voltage value in the parallel resistor disconnected state—the voltage values ​​under both states. These two voltage values ​​are then used to determine whether the insulation resistance in the high-voltage power supply unit meets the requirements, thus achieving insulation resistance monitoring in the high-voltage power supply unit. It is worth noting that insulation resistance monitoring can begin continuously when the high voltage is applied, or it can be performed at preset time intervals or under defined trigger conditions; no limitation is imposed here.

[0108] Step S20: Monitor the insulation resistance in the high-voltage power supply unit based on the first voltage value and the second voltage value.

[0109] In this embodiment, after determining the first and second voltage values, the insulation resistance in the high-voltage power supply unit is monitored based on these values. The main process involves establishing two equations based on the two voltage values, with only two unknowns: the resistance values ​​of the two insulation resistors in the high-voltage power supply unit. These equations and the two unknowns are then solved to determine the resistance values. These values ​​are then compared to preset resistance values ​​to determine if the preset resistance requirement is met. For example, if the insulation resistance value is greater than A, the user is informed that the insulation resistance meets the requirement; otherwise, the user is notified that the insulation resistance does not meet the requirement, and the user is alerted accordingly, or the high-voltage power supply is stopped to ensure power supply safety. This insulation resistance monitoring method is applied to an insulation resistance monitoring circuit. Through the design of this circuit, two sets of resistor voltage divider circuits and isolated sampling circuits are not required. Ultimately, the insulation resistance in the high-voltage power supply unit can be monitored based on the first and second voltage values, thereby reducing the cost of the insulation resistance monitoring circuit.

[0110] This embodiment provides an insulation resistance monitoring method applied to an insulation resistance monitoring circuit. The method acquires voltage values ​​collected by a voltage sampling subunit. These voltage values ​​include a first voltage value when the insulation resistance monitoring circuit is in a parallel resistor connected state and a second voltage value when the parallel resistor is disconnected. The insulation resistance in the high-voltage power supply unit is monitored based on the first and second voltage values. By acquiring the first voltage value in the parallel resistor connected state and the second voltage value in the parallel resistor disconnected state, the insulation resistance in the high-voltage power supply unit can ultimately be monitored based on the first and second voltage values. This avoids the need for separate resistor voltage divider circuits and isolation sampling circuits between the high-voltage positive terminal and the casing ground, and between the high-voltage negative terminal and the casing ground, as required in existing technologies to achieve insulation resistance monitoring. This insulation resistance monitoring circuit monitors resistance by collecting the first voltage value when the parallel resistor is connected and the second voltage value when the parallel resistor is disconnected, thus realizing a new method of insulation resistance monitoring. Furthermore, through the design of the insulation resistance monitoring circuit, two sets of resistor voltage divider circuits and isolation sampling circuits are not required. Ultimately, the insulation resistance in the high-voltage power supply unit can be monitored based on the first and second voltage values, thereby reducing the cost of the insulation resistance monitoring circuit.

[0111] In one embodiment, based on a first embodiment of the insulation resistance monitoring method, a second embodiment of this application is proposed, comprising the step of monitoring the insulation resistance in a high-voltage power supply unit according to a first voltage value and a second voltage value, including:

[0112] Step S21: Determine the preset sampling ratio coefficient, the total resistance value of the resistor voltage divider subunit, the parallel resistance value of the parallel resistor in the parallel resistor control subunit, and the voltage value of the high voltage power supply.

[0113] Step S22: Establish the first current equation based on the first voltage value, sampling ratio coefficient, total resistance value, parallel resistance value, and voltage value;

[0114] Step S23: Establish a second current equation based on the second voltage value, sampling ratio coefficient, total resistance value and voltage value. The first current equation and the second current equation are both current equations established about the resistance values ​​of the first insulation resistance and the second insulation resistance in the high-voltage power supply unit.

[0115] Step S24: Determine the first resistance value of the first insulation resistance and the second resistance value of the second insulation resistance based on the first current equation and the second current equation.

[0116] In this embodiment, when monitoring the insulation resistance in the high-voltage power supply unit, the controller will first determine the preset sampling ratio coefficient, the total resistance value of the voltage divider subunit, the parallel resistance value of the parallel resistor in the parallel resistor control subunit, and the voltage value of the high-voltage power supply. The sampling ratio coefficient refers to the ratio of voltage division sampling in the voltage divider subunit, i.e., M mentioned earlier. The total resistance value refers to the sum of all resistances in the voltage divider subunit, i.e., R1 mentioned earlier. The parallel resistance value refers to the resistance value of the parallel resistor in the parallel resistor control subunit, i.e., R0 mentioned earlier. The voltage value refers to the voltage value of the high-voltage power supply, i.e., VDC mentioned earlier. Combined with the second voltage value VS1 and the first voltage value VS11, two formulas of formula (1) can be established, namely the first current equation and the second current equation. Finally, the unknowns RP and RN can be solved based on the two current formulas, i.e., the first current equation and the second current equation determine the first resistance value of the first insulation resistance and the second resistance value of the second insulation resistance, so as to determine whether the entire high-voltage power supply unit is safe based on the two insulation resistance values, i.e., to achieve insulation resistance monitoring. Further, referring to... Figure 14 , Figure 14This is a schematic diagram of the implementation process of the insulation resistance monitoring method of the present invention. When high voltage is detected, the monitoring process will be executed based on the demand (insulation resistance monitoring demand). On the one hand, by controlling the open switch S1, the output voltage VS1 of the resistance voltage divider subunit is collected and obtained after a certain delay. On the other hand, by controlling the closed switch S1, the output voltage VS11 of the resistance voltage divider subunit is collected and obtained after a certain delay. The order of the two controls is not limited. Then, based on the output voltage VS1, the output voltage VS11 and other known quantities, the insulation resistance value in the high-voltage power supply unit is calculated, that is, by using the above formulas (1)-(4), the first resistance value of the first insulation resistance and the second resistance value of the second insulation resistance are finally obtained. It is determined whether the first resistance value and the second resistance value are within the defined safe range (or the preset resistance value requirement mentioned above). When they are within the safe range, the communication circuit will send the sampling result to the vehicle controller (at this time, it is assumed that the insulation resistance monitoring circuit is set in the air conditioning compressor in the vehicle, or it can be in other high-voltage devices, which is not limited here). Conversely, when they are not within the safe range, the communication circuit will send the fault to the vehicle controller to realize insulation resistance monitoring and ensure power supply safety.

[0117] Corresponding to the above embodiments, the present invention also proposes an air conditioning compressor.

[0118] The air conditioner compressor of this embodiment includes a controller, a motor and a compressor unit, wherein the controller is provided with an insulation resistance monitoring circuit;

[0119] The controller is connected to the motor, and the motor is connected to the compression unit;

[0120] The controller is used to perform the steps of the insulation resistance monitoring circuit described above.

[0121] According to an embodiment of the present invention, when the controller in the air conditioning compressor executes a program, the above-mentioned insulation resistance monitoring method is implemented. Based on the above-mentioned insulation resistance monitoring method, the voltage value collected by the voltage sampling subunit is obtained. The voltage value includes a first voltage value when the insulation resistance monitoring circuit is in a parallel resistor connection state and a second voltage value when the insulation resistance monitoring circuit is in a parallel resistor disconnect state. The insulation resistance in the high-voltage power supply unit is monitored according to the first voltage value and the second voltage value. In addition, by collecting the first voltage value in the parallel resistor connection state and the second voltage value in the parallel resistor disconnect state, a new insulation resistance monitoring method is realized. On the other hand, through the design of the insulation resistance monitoring circuit, it is not necessary to have two sets of resistor voltage divider circuits and isolation sampling circuits. Ultimately, the insulation resistance in the high-voltage power supply unit can be monitored based on the first voltage value and the second voltage value, thereby reducing the cost of the insulation resistance monitoring circuit.

[0122] The controller incorporates an insulation resistance monitoring circuit connected to the motor. A voltage divider circuit and a sampling circuit are then designed to monitor the insulation resistance in the high-voltage power supply unit. The motor drives the compressor section to function as an air conditioning compressor. It's worth noting that the air conditioning compressor can also include other hardware, such as a housing and circuit board, to separately arrange the high-voltage power supply unit and insulation detection unit within the insulation resistance monitoring circuit on the circuit board. The circuit board, its circuitry, and the motor are then encapsulated within the housing to form the air conditioning compressor. The controller controls the insulation resistance monitoring circuit to monitor the insulation resistance in the high-voltage power supply unit and also drives the corresponding motor controller to control the motor. It's also worth noting that the controller can be integrated with the control chip in the insulation resistance monitoring circuit into a single controller to reduce the number of controllers required. The insulation resistance monitoring circuit can also be integrated into other high-voltage operating circuits, such as PTC (Positive Temperature Coefficient) heaters.

[0123] Corresponding to the above embodiments, the present invention also proposes a vehicle.

[0124] The vehicle in this embodiment of the invention includes an air conditioning compressor, which is used to perform the steps of the above-described insulation resistance monitoring method.

[0125] The air conditioning compressor can be installed on the vehicle. Monitoring the insulation resistance of the high-voltage power supply unit can be achieved simply by designing a single set of resistor voltage divider circuits and sampling circuits, thus solving the technical problem of high cost for insulation resistance monitoring circuits. It is worth noting that other hardware can also be installed on the vehicle; these will not be detailed here. The entire air conditioning compressor can be installed on the vehicle or on other products; this is not a limitation.

[0126] The present invention also provides an air conditioning compressor, as shown in the reference. Figure 15 , Figure 15 This is a schematic diagram of an air conditioner compressor module of the present invention, wherein the air conditioner compressor includes:

[0127] Information acquisition module A01 is used to acquire the voltage value collected by the voltage sampling subunit, wherein the voltage value includes a first voltage value when the insulation resistance monitoring circuit is in the parallel resistor connection state and a second voltage value when the insulation resistance monitoring circuit is in the parallel resistor disconnect state;

[0128] The resistance monitoring module A02 is used to monitor the insulation resistance in the high-voltage power supply unit based on the first voltage value and the second voltage value.

[0129] The methods executed by the above-mentioned program modules can be referred to in the various embodiments of the optimization method of internal linkage of the present invention, and will not be repeated here.

[0130] The present invention also provides a storage medium.

[0131] The present invention stores an insulation resistance monitoring circuit program executed by an air conditioner compressor on a storage medium. When the insulation resistance monitoring circuit program is executed by a processor, it implements the steps of the insulation resistance monitoring circuit as described above.

[0132] The method implemented when the insulation resistance monitoring circuit program running on the processor is executed can be referred to in various embodiments of the insulation resistance monitoring method of the present invention, and will not be repeated here.

[0133] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0134] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0135] The above description is merely an optional embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. An insulation resistance monitoring circuit, characterized in that, The insulation resistance monitoring circuit includes a high-voltage power supply unit and an insulation detection unit. The high-voltage power supply unit is connected to the insulation detection unit and an external high-voltage power supply. The insulation detection unit includes: A parallel resistor control subunit is provided, which is connected to the first terminal and the second terminal of the high voltage power supply unit. The parallel resistor control subunit is used to control the insulation resistance monitoring circuit to be in a parallel resistor connected state and a parallel resistor disconnected state. A voltage divider unit with a resistance, wherein the input terminal of the voltage divider unit is connected to the third terminal and the second terminal of the high-voltage power supply unit. A voltage sampling subunit, the input terminal of which is connected to the output terminal of the resistor voltage divider subunit, is used to collect a first voltage value when the parallel resistor is connected and a second voltage value when the parallel resistor is disconnected based on the resistor voltage divider subunit; A control chip is connected to the output terminal of the voltage sampling subunit. The control chip is used to monitor the insulation resistance in the high-voltage power supply unit based on the first voltage value and the second voltage value.

2. The insulation resistance monitoring circuit as described in claim 1, characterized in that, The parallel resistor control subunit includes: A control switch, the first end of which is connected to the first end of the high-voltage power supply unit; A parallel resistor is provided, with its first end connected to the second end of the control switch and its second end connected to the second end of the high-voltage power supply unit.

3. The insulation resistance monitoring circuit as described in claim 1, characterized in that, The resistive voltage divider subunit includes: Multiple voltage divider resistors are connected in sequence. The first end of the first voltage divider resistor is connected to the third end of the high-voltage power supply unit, and the second end of the last voltage divider resistor is connected to the second end of the high-voltage power supply unit. The first end of the output resistor in the voltage divider resistor is connected to the input end of the voltage sampling subunit.

4. The insulation resistance monitoring circuit as described in claim 1, characterized in that, The high-voltage power supply unit includes a high-voltage positive terminal, a high-voltage negative terminal, and a casing ground; The high-voltage positive terminal serves as the first terminal of the high-voltage power supply unit, the high-voltage negative terminal serves as the third terminal of the high-voltage power supply unit, and the outer casing ground serves as the second terminal of the high-voltage power supply unit, or... The high-voltage positive terminal serves as the third terminal of the high-voltage power supply unit, the high-voltage negative terminal serves as the first terminal of the high-voltage power supply unit, and the outer casing ground serves as the second terminal of the high-voltage power supply unit.

5. The insulation resistance monitoring circuit as described in claim 4, characterized in that, The high-voltage power supply unit includes: A first insulation resistor, wherein a first end of the first insulation resistor is connected to the positive terminal of the high voltage power supply and the high voltage positive terminal, and a second end of the first insulation resistor is connected to the ground of the casing; The second insulation resistor has its second end connected to the negative terminal of the high-voltage power supply and the high-voltage negative terminal, and its first end connected to the ground of the casing.

6. The insulation resistance monitoring circuit according to any one of claims 1 to 5, characterized in that, The control chip includes a high-voltage control chip and a low-voltage control chip; When the control chip is the high-voltage control chip, the voltage sampling subunit includes an isolated sampling operational amplifier chip, wherein the input terminal of the isolated sampling operational amplifier chip is connected to the output terminal of the resistor voltage divider subunit, and the output terminal of the isolated sampling operational amplifier chip is connected to the high-voltage control chip; When the control chip is the low-voltage control chip, the voltage sampling subunit includes a sampling operational amplifier chip, wherein the input terminal of the sampling operational amplifier chip is connected to the output terminal of the resistor voltage divider subunit, and the output terminal of the sampling operational amplifier chip is connected to the high-voltage control chip.

7. A method for monitoring insulation resistance, characterized in that, The insulation resistance monitoring method is applied to the insulation resistance monitoring circuit as described in any one of claims 1 to 6, and the insulation resistance monitoring method includes the following steps: The voltage value collected by the voltage sampling subunit is obtained, wherein the voltage value includes a first voltage value when the insulation resistance monitoring circuit is in the state of parallel resistor connection and a second voltage value when the insulation resistance monitoring circuit is in the state of parallel resistor disconnection; The insulation resistance in the high-voltage power supply unit is monitored based on the first voltage value and the second voltage value.

8. The insulation resistance monitoring method as described in claim 7, characterized in that, The step of monitoring the insulation resistance in the high-voltage power supply unit based on the first voltage value and the second voltage value includes: Determine the preset sampling ratio coefficient, the total resistance value of the resistor voltage divider subunit, the parallel resistance value of the parallel resistor in the parallel resistor control subunit, and the voltage value of the high voltage power supply; A first current equation is established based on the first voltage value, the sampling ratio coefficient, the total resistance value, the parallel resistance value, and the voltage value; A second current equation is established based on the second voltage value, the sampling ratio coefficient, the total resistance value, and the voltage value. The first current equation and the second current equation are both current equations established about the resistance values ​​of the first insulation resistance and the second insulation resistance in the high-voltage power supply unit. The first resistance value of the first insulation resistor and the second resistance value of the second insulation resistor are determined based on the first current equation and the second current equation.

9. An air conditioning compressor, characterized in that, The air conditioning compressor includes a controller, a motor, and a compressor unit, wherein the controller is provided with an insulation resistance monitoring circuit as described in any one of claims 1 to 6; The controller is connected to the motor, and the motor is connected to the compression unit; The controller is used to perform the steps of the insulation resistance monitoring method as described in any one of claims 7 to 8.

10. A vehicle, characterized in that, The vehicle includes an air conditioning compressor, which is used to perform the steps of the insulation resistance monitoring method as described in any one of claims 7 to 8.

Images