CN217994165U - High voltage system of a vehicle and the vehicle - Google Patents

Abstract

The present disclosure relates to a high-voltage system (100) of a vehicle and a vehicle, the high-voltage system (100) comprising: a power cell (1); the motor controller (2) is connected with the power battery (1) and is used for converting direct current output by the power battery (1) into alternating current and supplying the alternating current to the motor (3); the neutral point (3 d) of the motor (3) is connected with a first node (1 a) inside the power battery (1); and the insulation resistance detection module (4) is connected with the power battery (1) and is used for detecting the insulation resistance value of the high-voltage system (100). Through the technical scheme, the neutral point of the motor is connected with the first node inside the power battery, so that the electric leakage of the motor is equivalent to the electric leakage of the first node inside the power battery. Like this, at the live-line work's of motor in-process, if the motor leaks electricity, can be detected out by the insulation resistance module to the user in time maintains, improves the security that the vehicle used.

Description

High voltage system of a vehicle and the vehicle

technical field

The present disclosure relates to the field of vehicles, in particular, to a high-voltage system of a vehicle and the vehicle.

Background technique

Most of the output voltages of electric vehicle power batteries are between 72V and 600V, and the highest can reach more than 600V. Under normal environmental conditions, for the human body, the "safety extra-low voltage" that allows continuous contact is a voltage below 36V. The DC voltage output by the power battery of an electric vehicle has far exceeded this "safety extra-low voltage". In order to ensure the safety of personnel, the insulation performance of the high-voltage system of the vehicle should meet the corresponding national standards. As an important part of confirming the insulation performance of the vehicle's high-voltage system, the measurement of the insulation resistance of the vehicle's high-voltage system is particularly important.

Utility model content

The object of the present disclosure is to provide a high-voltage system of a vehicle and a vehicle capable of performing insulation resistance detection of the high-voltage system in consideration of the insulation resistance of a motor.

In order to achieve the above purpose, the present disclosure provides a high voltage system of a vehicle, including:

Power Battery;

A motor controller, connected to the power battery, for converting the direct current output by the power battery into alternating current and supplying it to the motor;

The motor, the neutral point of the motor is connected to the first node inside the power battery;

The insulation resistance detection module is connected with the power battery and is used to detect the insulation resistance of the high voltage system.

Optionally, the high voltage system further includes a first switch module, and the neutral point of the motor is connected to the first node through the first switch module.

Optionally, the first switch module includes any one of the following: a relay, a triode, and a metal-oxide semiconductor field effect transistor (MOSFET).

Optionally, the first node is a node that equally divides the potential difference of the power battery.

Optionally, the motor controller is a three-phase bridge arm inverter.

Optionally, the insulation resistance detection module includes a balanced bridge circuit or an unbalanced bridge circuit.

Optionally, the insulation resistance detection module includes a first resistor, a second resistor, a third resistor, a fourth resistor and a switch tube, the positive pole of the power battery is connected to one end of the first resistor, and the first resistor The other end of the second resistor is respectively connected to one end of the second resistor and the first end of the switch tube, the other end of the second resistor is respectively connected to one end of the third resistor and the ground wire, and the other end of the third resistor is connected to the ground wire. One end is connected to the negative pole of the power battery through the fourth resistor, and the second end of the switch tube is connected to the negative pole of the power battery, wherein, when the third end of the switch tube receives a control signal, the The first end of the switch tube is connected to the second end of the switch tube.

Optionally, the switch tube is a triode or MOSFET.

The present disclosure also provides a vehicle, which includes the above-mentioned high-voltage system.

Through the above technical solution, the neutral point of the motor is connected to the first node inside the power battery, so that the leakage of the motor is equivalent to the leakage of the first node inside the power battery. In this way, when the motor is working with electricity, if the motor leaks electricity, it can be detected by the insulation resistance module, so that the user can perform maintenance in time and improve the safety of the vehicle.

Other features and advantages of the present disclosure will be described in detail in the detailed description that follows.

Description of drawings

The accompanying drawings are used to provide a further understanding of the present disclosure, and constitute a part of the description, together with the following specific embodiments, are used to explain the present disclosure, but do not constitute a limitation to the present disclosure. In the attached picture:

FIG. 1 is a block diagram of a high voltage system of a vehicle provided in an exemplary embodiment according to the present disclosure.

Fig. 2 is a circuit diagram of a motor controller in a high voltage system of a vehicle according to an exemplary embodiment of the present disclosure.

Fig. 3 is a schematic circuit diagram of a motor in a high-voltage system of a vehicle provided by an exemplary embodiment of the present disclosure.

Fig. 4 is a schematic circuit diagram of an insulation resistance detection module in a high voltage system of a vehicle provided by an exemplary embodiment of the present disclosure.

Fig. 5 is a schematic circuit diagram of a high voltage system of a vehicle provided in an exemplary embodiment of the present disclosure.

Fig. 6 is a block diagram of a high voltage system of a vehicle provided in still another exemplary embodiment of the present disclosure.

Fig. 7 is a schematic circuit diagram of a high voltage system of a vehicle provided in yet another exemplary embodiment of the present disclosure.

Explanation of reference signs

1-Power battery, 2-Motor controller, 3-Motor, 4-Insulation resistance detection module, 5-Single battery, 6-First switch module, 100-High voltage system;

1a - the first node;

2a-first input of motor controller, 2b-second input of motor controller, 2c-first output of motor controller, 2d-second output of motor controller, 2e-motor controller third output terminal;

3a-the first input terminal of the motor, 3b-the second input terminal of the motor, 3c-the third input terminal of the motor, 3d-the neutral point of the motor;

4a-the first end of the insulation resistance detection module, 4b-the second end of the insulation resistance detection module;

R1-first resistor, R2-second resistor, R3-third resistor, R4-fourth resistor, S-switch, S1-first end of switch, S2-second end of switch, S3-switch the third end of the tube

detailed description

Specific embodiments of the present disclosure will be described in detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described here are only used to illustrate and explain the present disclosure, and are not intended to limit the present disclosure.

In the related art, when detecting the insulation resistance of the high-voltage system, if it is desired that the detected insulation resistance can take into account the insulation resistance of the motor, it is necessary to control the upper three bridges or the lower three bridges of the motor controller (ie, the motor controller The upper three-bridge switching tube or the lower three-bridge switching tube in the motor is turned on), so that the motor is connected to the positive pole or negative pole of the high-voltage bus through the switching tube in the motor controller. In this case, if the insulation resistance of the motor to the ground is small, the detected insulation resistance of the positive pole of the DC bus or the insulation resistance of the negative pole of the DC bus to the ground will also be small, so the measurement results can reflect the insulation resistance of the motor. .

As mentioned above, in order to complete the insulation resistance detection of the high-voltage system considering the insulation resistance of the motor, the motor controller needs to open the wave in a specific way (the upper three-bridge open-wave or the lower three-bridge open-wave). However, when the vehicle is performing functions such as "drive driving", "self-heating" and "motor boost charging", since the motor controller needs to open the wave according to the specified logic, the vehicle cannot complete the insulation resistance detection of the high-voltage system considering the insulation resistance of the motor. While these functions are in progress, the motor is under high voltage throughout the process. If the insulation resistance of the motor to the ground is small at this time, it will cause the high voltage system to leak to the ground, which has a great potential safety hazard.

When the vehicle is performing functions such as "drive driving", "self-heating", and "motor boost charging", the motor will be charged, and it is necessary to detect its leakage. However, the aforementioned method of detecting the insulation resistance of the high-voltage system can only be activated when the motor controller is in an idle state (the motor controller is not activated according to the specified logic for realizing the functions of "driving drive", "self-heating" and "motor boost charging". The insulation resistance detection of the high-voltage system considering the insulation resistance of the motor is completed in the wave). At this time, the motor is originally isolated from the high-voltage system through the switch tube, without high-voltage electricity, and there is no risk of electric shock. Therefore, this way of detecting the insulation resistance of high-voltage systems has its limitations. All in all, the solution for detecting the insulation resistance of the high-voltage system in the related art cannot perform insulation detection when the motor is live. Based on this, the inventor proposes a high voltage system of a vehicle.

FIG. 1 is a block diagram of a high voltage system of a vehicle provided in an exemplary embodiment according to the present disclosure. As shown in FIG. 1 , the high voltage system 100 includes a power battery 1 , a motor controller 2 , a motor 3 and an insulation resistance detection module 4 . As shown in FIG. 1 , the power battery 1 may include multiple single cells 5 .

The motor controller 2 is connected with the power battery 1 and is used to convert the DC power output by the power battery 1 into AC power and provide it to the motor 3 . Fig. 2 is a circuit diagram of a motor controller in a high voltage system of a vehicle according to an exemplary embodiment of the present disclosure. As shown in FIG. 2 , the motor controller 2 may include a three-phase inverter bridge. The motor controller 2 can input the DC power output by the power battery 1 through the first input terminal 2a of the motor controller and the second input terminal 2b of the motor controller, and convert the DC power into a three-phase AC power through the three-phase inverter bridge and pass it through the motor The first output terminal 2c of the controller, the second output terminal 2d of the motor controller, and the third output terminal 2e of the motor controller are provided to the motor 3 . In one embodiment, the motor controller 2 may be a controller that controls a multi-phase motor.

Fig. 3 is a schematic circuit diagram of a motor in a high-voltage system of a vehicle provided by an exemplary embodiment of the present disclosure. As shown in FIG. 3 , the motor 3 may include three-phase windings. The motor 3 can input the three-phase AC power provided by the motor controller 2 through the first input terminal 3a of the motor, the second input terminal 3b of the motor, and the third input terminal 3c of the motor. In one embodiment, the motor 3 may be a multi-phase motor.

The neutral point is the common point of the three-phase winding or multi-phase winding star connection. As shown in FIG. 3 , the neutral point 3 d of the motor may be a common point of the three-phase windings of the motor 3 . The neutral point 3d of the motor 3 is connected to the first node inside the power battery 1 . The first node refers to a point between two single cells 5 in the power battery 1 . For example, if the power battery 1 is composed of 100 single cells 5 connected in series, the first node can be the node between the 23rd single cell 5 and the 24th single cell 5, or the node between the 50th single cell 5 and the node between the 51st cell 5.

The insulation resistance detection module 4 is connected to the power battery 1 and is used to detect the insulation resistance of the high voltage system 100 . Fig. 4 is a schematic circuit diagram of an insulation resistance detection module in a high voltage system of a vehicle provided by an exemplary embodiment of the present disclosure. As shown in Figure 4, the insulation resistance detection module 4 can include a switch tube and a plurality of resistors, and the first end 4a of the insulation resistance detection module and the second end 4b of the insulation resistance detection module can be connected to the positive pole of the power battery 1 and the power battery respectively. 1 is connected to the negative pole.

After the first end 4a of the insulation resistance detection module and the second end 4b of the insulation resistance detection module are respectively connected to the positive pole of the power battery 1 and the negative pole of the power battery 1, the positive pole of the power battery 1 and the negative pole of the power battery 1 can be insulated The resistance in the resistance detection module 4 is grounded. The insulation resistance detection module 4 may also be a circuit structure applicable to the detection of insulation resistance by an AC signal injection method.

Fig. 5 is a schematic circuit diagram of a high voltage system of a vehicle provided in an exemplary embodiment of the present disclosure. Referring to Figure 1 and Figure 5, the neutral point 3d of the motor is connected to the first node 1a inside the power battery 1, therefore, the small resistance of the motor 3 to ground can be equivalent to the ground resistance of the first node 1a inside the power battery 1 The resistance is small. In other words, if the insulation resistance of the motor 3 is small, the insulation resistance detected by the insulation resistance detection module 4 is also small. During the process of the vehicle performing functions such as "driving", "self-heating", and "motor boost charging", if the insulation resistance of the motor 3 is lower than the preset resistance threshold, the insulation resistance detected by the insulation resistance detection module 4 It will also be lower than the preset resistance threshold; if the insulation resistance detected by the insulation resistance detection module 4 is lower than the preset resistance threshold, it may be because the insulation resistance of the motor 3 is lower than the preset resistance threshold. Therefore, for the high-voltage system 100 provided in the present disclosure, if the motor’s insulation resistance is lower than the preset The resistance threshold can be detected.

Through the above technical solution, the neutral point of the motor is connected to the first node inside the power battery, so that the leakage of the motor is equivalent to the leakage of the first node inside the power battery. In this way, when the motor is working with electricity, if the motor leaks electricity, it can be detected by the insulation resistance module, so that the user can perform maintenance in time and improve the safety of the vehicle.

Fig. 6 is a block diagram of a high voltage system of a vehicle provided in still another exemplary embodiment of the present disclosure. Fig. 7 is a schematic circuit diagram of a high voltage system of a vehicle provided in yet another exemplary embodiment of the present disclosure. As shown in FIG. 6 and FIG. 7 , the high voltage system 100 further includes a first switch module 6 , and the neutral point 3 d of the motor 3 is connected to the first node 1 a through the first switch module 6 .

In this embodiment, the first switch module 6 is arranged between the neutral point 3d of the motor 3 and the first node 1a. In this way, when the insulation resistance of the high-voltage system is not detected, the connection between the motor 3 and the first node 1 a can be disconnected by disconnecting the first switch module 6 . The function of the first switch module 6 is mainly to ensure that the neutral point 3d of the motor 3 does not carry high voltage when the vehicle is not powered on (the first switch module 6 is disconnected).

In addition, after the first switch module 6 is closed, if the insulation resistance detected by the insulation resistance detection module 4 is less than the preset resistance threshold, the first switch module 6 can be turned off, and the insulation resistance detection module 4 continues to detect the insulation resistance. resistance. After disconnecting the first switch module 6, if the insulation resistance detected by the insulation resistance detection module 4 is greater than the preset resistance threshold, it can be determined that the electric motor 3 is leaking; if the insulation resistance detected by the insulation resistance detection module 4 is still less than the preset resistance threshold, it may not be motor 3 leakage. The method of finding fault points through comparative analysis is well known to those skilled in the art, and will not be described too much here.

A first switch module is set between the neutral point of the motor and the first node, one of which can disconnect the connection between the neutral point of the motor and the first node inside the power battery when the insulation resistance of the high-voltage system is not detected, and the other can When the insulation resistance detection module detects that there is leakage in the high-voltage system, the scope of investigation of the leakage point is reduced.

In yet another embodiment, the first switch module 6 includes any one of the following: a relay, a triode, and a metal-oxide-semiconductor field-effect transistor (Metal-Oxide-Semiconductor Field-Effect Transistor, MOSFET).

Relays, transistors and MOSFETs are all devices that can be connected to strong current (voltage above 36V) and can be controlled by weak current (voltage below 32V). Use relays or transistors or MOSFETs to control the first The connection and disconnection of a node 1a to the neutral point 3d of the motor improves the safety of the high-voltage system 100 in use.

In yet another embodiment, the first node is a node that equally divides the potential difference of the power battery 1 .

For example, the potential difference between the positive pole and the negative pole of the power battery 1 is 300V, and the node where the potential difference of the power battery 1 is evenly divided is the node whose potential is 150V higher than the negative pole of the power battery 1 . If the power battery 1 is composed of 200 single cells 5 with a voltage of 1.5V connected in series, the node that divides the potential difference of the power battery 1 equally is between the 100th single cell 5 and the 101st single cell 5 Between, easy to find, easy to maintain.

In yet another embodiment, the motor controller 2 is a three-phase bridge arm inverter. The three-phase arm inverter can convert direct current into three-phase alternating current, and has a simple structure and good reliability.

In yet another embodiment, the insulation resistance detection module 4 includes a balanced bridge circuit or an unbalanced bridge circuit. That is to say, the insulation resistance detection module 4 may be a circuit structure applicable to the measurement of insulation resistance by the external resistance method. If the insulation resistance detection module 4 is a circuit structure suitable for measuring insulation resistance by the AC signal injection method, the AC signal injected between the positive pole and the negative pole of the power battery 1 may form ripple interference in the high-voltage system 100, which may affect the high-voltage system 100. normal operation of the system 100. If the insulation resistance detection module 4 is a circuit structure suitable for measuring insulation resistance by the external resistance method, when the insulation resistance detection module 4 is used to detect the insulation resistance of the high voltage system 100, the high voltage system 100 can run more stably. The structure of the balanced bridge circuit and the unbalanced bridge circuit is simple. If the insulation resistance detection module 4 is a balanced bridge circuit or an unbalanced bridge circuit, it can quickly detect the insulation resistance of the high voltage system 100 .

In yet another embodiment, as shown in FIG. 4 , the insulation resistance detection module 4 includes a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4 and a switch tube S, and the positive pole of the power battery 1 is connected to the second resistor. One end of a resistor R1 (i.e. the first end 4a of the insulation resistance detection module), the other end of the first resistor R1 is respectively connected to one end of the second resistor R2 and the first end S1 of the switch tube S, and the other end of the second resistor R2 Connect one end of the third resistor R3 and the ground wire respectively, the other end of the third resistor R3 is connected to the negative pole of the power battery 1 through the fourth resistor R4, and the second end S2 of the switch tube S (that is, the second end of the insulation resistance detection module 4b) Connect to the negative pole of the power battery 1, wherein, when the third terminal S3 of the switching tube S receives the control signal, the first terminal S1 of the switching tube S and the second terminal S2 of the switching tube S are turned on. Utilizing the circuit structure of the insulation resistance detection module 4 provided in this embodiment, the change of the voltage and current to ground of the DC bus (positive and negative poles of the power battery 1 ) of the high-voltage system 100 can be based on the switch tube S being turned on and off. The insulation resistance of the high voltage system 100 is quickly detected.

In yet another embodiment, the switch tube S is a transistor or a MOSFET. In this way, the switching on and off of the switching tube S can be quickly controlled using a driving signal not higher than 32V, and the insulation resistance of the high voltage system 100 can be detected more safely and efficiently.

The present disclosure also provides a vehicle, which includes the above-mentioned high voltage system 100 .

The preferred embodiments of the present disclosure have been described in detail above in conjunction with the accompanying drawings. However, the present disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure. These simple modifications all belong to the protection scope of the present disclosure.

In addition, it should be noted that the various specific technical features described in the above specific implementation manners may be combined in any suitable manner if there is no contradiction. In order to avoid unnecessary repetition, various possible combinations are not further described in this disclosure.

In addition, various implementations of the present disclosure can be combined arbitrarily, as long as they do not violate the idea of the present disclosure, they should also be regarded as the content disclosed in the present disclosure.

Claims (9)

1. A high-voltage system (100) of a vehicle, comprising:

a power cell (1);

the motor controller (2) is connected with the power battery (1) and is used for converting the direct current output by the power battery (1) into alternating current and supplying the alternating current to the motor (3);

the neutral point (3 d) of the motor (3) is connected with a first node (1 a) inside the power battery (1);

and the insulation resistance detection module (4) is connected with the power battery (1) and is used for detecting the insulation resistance value of the high-voltage system (100).

2. The high voltage system (100) according to claim 1, characterized in that the high voltage system (100) further comprises a first switch module (6), and the neutral point (3 d) of the electrical machine (3) is connected to the first node (1 a) through the first switch module (6).

3. The high voltage system (100) according to claim 2, wherein the first switch module (6) comprises any one of the following: relays, triodes, and metal-oxide semiconductor field effect transistors MOSFETs.

4. The high voltage system (100) according to claim 1, wherein the first node (1 a) is a node that averages the potential difference of the power cell (1).

5. The high-voltage system (100) according to claim 1, wherein the motor controller (2) is a three-phase bridge arm inverter.

6. The high voltage system (100) according to claim 1, wherein the insulation resistance detection module (4) comprises a balanced bridge circuit or an unbalanced bridge circuit.

7. The high-voltage system (100) according to claim 1, wherein the insulation resistance detection module (4) comprises a first resistor (R1), a second resistor (R2), a third resistor (R3), a fourth resistor (R4) and a switch tube (S), the positive terminal of the power battery (1) is connected to one terminal of the first resistor (R1), the other terminal of the first resistor (R1) is connected to one terminal of the second resistor (R2) and the first terminal (S1) of the switch tube (S), the other terminal of the second resistor (R2) is connected to one terminal of the third resistor (R3) and the ground, the other terminal of the third resistor (R3) is connected to the negative terminal of the power battery (1) through the fourth resistor (R4), the second terminal (S2) of the switch tube (S) is connected to the negative terminal of the power battery (1), and when the third terminal (S3) of the switch tube (S) receives a control signal, the second terminal (S1) of the switch tube (S) and the second terminal (S2) of the switch tube (S) are connected to the negative terminal of the power battery (1).

8. The high voltage system (100) according to claim 7, wherein the switching tube (S) is a triode or a MOSFET.

9. A vehicle, characterized in that the vehicle comprises a high-voltage system (100) according to any one of claims 1-8.

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