High-voltage system of electric automobile
By integrating pre-charge circuits into the high-voltage battery system and optimizing load circuits, the complexity and cost of electric vehicle high-voltage systems are reduced, ensuring stable and efficient operation.
Patent Information
- Application Number
- CN202421840127.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-30
- Publication Date
- 2025-07-15
- Estimated Expiration
- 2034-07-30
AI Technical Summary
There are many precharge circuits in the high-voltage distribution box of existing electric vehicles, which leads to high costs.
The precharge circuit is designed into the high-voltage power battery system, and the load circuit in the high-voltage distribution box is optimized to ensure uniform precharge of the load, achieve stable start-up and operation, reduce start-up shock current, and simplify circuit design.
Through unified pre-charge design, the complexity and cost of the high-voltage system are reduced, and the stable and reliable operation of the high-voltage system is achieved.
Smart Images
Figure CN223100476U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of electric vehicles, and particularly relates to a high-voltage system of an electric vehicle. Background Technique
[0002] With the rapid development of electric vehicles, the design of high-voltage components of electric vehicles has gradually increased. As a voltage source, the high-voltage power battery system, and each component is connected in parallel as a load in the high-voltage circuit. Different circuits and control methods need to be designed to achieve functions. Each high-voltage component has a resistive load and a capacitive load. The circuit design and control method of the high-voltage system need to be reasonably designed and the control logic is clear to achieve the functions and stable and reliable operation of the system.
[0003] Because the electrical characteristics of each high-voltage component are different, some are resistive loads, some are capacitive loads, some loads start working as soon as the power is turned on, some loads need to be pre-charged to ensure the stable start of the circuit. Some resistive loads start working as soon as the electric vehicle starts, and some are randomly turned on or off by the customer during driving. Therefore, the design of the high-voltage circuit is relatively complex. Many contactors and pre-charge resistors are used in the design of the high-voltage circuit. Capacitive loads all need to be pre-charged. A pre-charge circuit is designed in front of each capacitive load in the high-voltage distribution box. The overall price cost is relatively high, which increases the cost of the whole vehicle. Summary of the Utility Model
[0004] The technical problem solved by the utility model is to provide a high-voltage system of an electric vehicle to solve the problem of high cost caused by many pre-charge circuits in the high-voltage distribution box of the existing electric vehicle.
[0005] The basic solution provided by the utility model: A high-voltage system of an electric vehicle includes a high-voltage power battery system, a high-voltage distribution box, a control component, and a high-voltage component;
[0006] The high-voltage power battery system includes a voltage source, a pre-charge circuit, and a power interface. The voltage source and the pre-charge circuit are connected in parallel. The positive and negative poles of the voltage source are connected to the input of the power interface, and the power interface is connected to the high-voltage distribution box; the high-voltage distribution box is connected to the high-voltage component;
[0007] The control component is used to control the on-off state of the voltage source, the state of the pre-charge circuit, and the power supply state of the high-voltage distribution box.
[0008] Further, the pre-charge circuit includes a pre-charge resistor and a pre-charge contactor, and the pre-charge resistor and the pre-charge contactor are connected in parallel on the positive circuit connecting the voltage source and the high-voltage distribution box.
[0009] Further, the control component includes a main circuit negative contactor, a main circuit positive contactor, and a main circuit fuse. The main circuit negative contactor is located on the negative circuit connecting the voltage source and the high-voltage distribution box, and the main circuit positive contactor is located on the positive circuit connecting the voltage source and the high-voltage distribution box. The main circuit fuse controls the power supply on-off state of the voltage source.
[0010] Further, the high-voltage components include multiple capacitive loads and multiple resistive loads. The high-voltage distribution box includes multiple capacitive load power supply circuits, multiple resistive load power supply circuits, and corresponding power supply interfaces that are connected in parallel with the voltage source. The input ends of the multiple capacitive load power supply circuits and the multiple resistive load power supply circuits are connected to the output of the power supply interface of the high-voltage power battery system, and the output ends of the multiple capacitive load power supply circuits and the multiple resistive load power supply circuits are connected to the input of the power supply interface.
[0011] Further, the control component also includes multiple capacitive load fuses and multiple resistive load contactors. The multiple capacitive load contactors are located on each capacitive load power supply circuit and are connected in parallel with the resistive load contactors.
[0012] Further, the high-voltage power battery system also includes a fast charge input interface, which is connected to an external fast charge power supply.
[0013] Further, the control component also includes a fast charge contactor, which is used to control the on-off state of the fast charge input interface.
[0014] Further, a battery heating fuse, a battery heating contactor, and a battery heating PTC are also included on the power supply circuit of the voltage source. The battery heating fuse, the battery heating contactor, and the battery heating PTC are used to provide protection for the voltage source.
[0015] Further, a communication component is also included, which is used to provide message commands for the control component.
[0016] The principle and advantages of the present utility model are as follows: In the prior art, the high-voltage power battery system does not have a pre-charge circuit designed. For the load components that need pre-charging, pre-charge circuits for each branch need to be set in the high-voltage distribution box. Coupled with the various high-voltage branches of the resistive loads, there are many high-voltage contactors and complex copper busbars and wires inside the entire high-voltage distribution box. The entire high-voltage circuit design is complex and the cost is relatively high.
[0017] In this application, a pre-charge circuit is designed into the high-voltage power battery system, and the load circuits in the high-voltage distribution box are optimized. When power is applied, the loads are pre-charged uniformly, which can prevent voltage spikes, reduce starting inrush current, protect circuit components, and enable stable startup and operation of each load. Compared with the existing technical solutions, in this application, the pre-charge circuit is designed inside the high-voltage power battery system, and multiple loads connected in parallel are regarded as one load, with better consistency in the entire high-voltage system. When the vehicle is powered on, it is pre-charged uniformly, and when powered off, it actively discharges through loads such as the motor controller, making the power-on and power-off logic of the whole vehicle clear, stable and reliable. Description of the Drawings
[0018] Figure 1 It is a schematic structural diagram of an embodiment of the present utility model. Detailed Description of the Specific Embodiment
[0019] The following is a further detailed description through specific embodiments:
[0020] The embodiment is basically as shown in the attached Figure 1 figures: A high-voltage component of an electric vehicle includes a high-voltage power battery system, a high-voltage distribution box, a control component, a high-voltage component, and a communication component. Specifically:
[0021] The high-voltage power battery system includes a voltage source, a pre-charge circuit, a power interface, and a fast-charge input interface. On the power circuit of the voltage source, there are also a battery heating fuse, a battery heating contactor, and a battery heating PTC. The voltage source and the pre-charge circuit are in parallel. The positive and negative poles of the voltage source are connected to the inputs of the power interface. Specifically, the negative pole of the voltage source is connected to one input terminal of the power interface, and the positive pole circuit of the voltage source is in parallel with the pre-charge circuit and then connected to the other input terminal of the power interface.
[0022] On the power circuit formed by the positive and negative poles of the power supply, a battery heating fuse, a battery heating contactor, and a battery heating PTC are provided for overheat protection of the voltage source.
[0023] The input terminal of the fast-charge input interface is connected to an external fast-charge power supply, and the output terminal is connected to the negative pole of the voltage source and the positive pole and the pre-charge circuit of the voltage source. Through the fast-charge input interface, the input current is pre-charged through the pre-charge circuit and then synchronously transmitted to the voltage source for charging. The on-off of the fast-charge input interface is controlled by a fast-charge contactor.
[0024] In this application, the pre-charge circuit includes a pre-charge resistor and a pre-charge contactor. The pre-charge resistor and the pre-charge contactor are connected in parallel on the positive electrode circuit where the voltage source is connected to the high-voltage distribution box. To achieve the on / off of the voltage source, it is realized through a control component. Specifically, in the high-voltage power battery system, the control component includes a main circuit negative contactor, a main circuit positive contactor, and a main circuit fuse. The main circuit negative contactor is located on the negative electrode circuit where the voltage source is connected to the high-voltage distribution box, and the main circuit positive contactor is located on the positive electrode circuit where the voltage source is connected to the high-voltage distribution box; the main circuit fuse controls the on / off state of the power supply of the voltage source.
[0025] The high-voltage distribution box is connected to the power supply interface. Inside the high-voltage distribution box, there are control circuits for multiple high-voltage components. To achieve the unified power-on and power-off of the high-voltage components, their control circuits are connected in parallel. Specifically:
[0026] The high-voltage components include multiple capacitive loads and multiple resistive loads. The high-voltage distribution box includes multiple capacitive load power supply circuits, multiple resistive load power supply circuits connected in parallel, and corresponding power supply interfaces. The input ends of the multiple capacitive load power supply circuits and the multiple resistive load power supply circuits are connected to the output of the power supply interface of the high-voltage power battery system, and the output ends of the multiple capacitive load power supply circuits and the multiple resistive load power supply circuits are connected to the input of the power supply interface; thus, after the high-voltage components are connected to their corresponding power supply interfaces, they can receive the power provided by the high-voltage distribution box.
[0027] To achieve the control of the high-voltage components, the control component in this application further includes multiple capacitive load fuses and multiple resistive load contactors. The multiple capacitive load contactors are located on each capacitive load power supply circuit and are connected in parallel with the resistive load contactors.
[0028] For example, among the high-voltage components, the capacitive loads include a DC / DC converter, a motor controller assembly, an on-vehicle charger, a PTC liquid heater, and an electric compressor, and the resistive load includes a PTC air heater. Therefore, on the power supply circuits of the capacitive loads, a DC / DC converter fuse, a motor controller assembly fuse, an on-vehicle charger fuse, a PTC liquid fuse, and an air conditioner fuse are respectively connected in parallel. At the same time, for the power supply circuit of the resistive load such as the PTC air heater, since it is often used together with the electric compressor, a PTC air heater contactor is connected in parallel on the circuit of the air conditioner fuse to control the PTC air heater.
[0029] In the entire high-voltage system of this application, the control of each contactor and high-voltage component is carried out through a communication component. Specifically, the communication component in this application is a CAN network. For example, when powering on, a closing or opening instruction is sent to the PTC air heater contactor through the CAN network to enable or cut off the high voltage input to the PTC air heater. When powering off, a stop work instruction is sent to each high-voltage component through the CAN network, and the corresponding control component is turned off according to the stop work instruction to achieve the power-off of each high-voltage component.
[0030] The specific implementation process is as follows: In this application, the pre-charge circuit is designed into the high-voltage power battery system, and the high-voltage power battery system becomes a voltage source with a pre-charge function. The motor controller assembly is connected in parallel with the voltage source through the high-voltage distribution box, the DC / DC converter is connected in parallel with the voltage source through the high-voltage distribution box, the on-vehicle charger is connected in parallel with the voltage source through the high-voltage distribution box, the PTC liquid heater is connected in parallel with the voltage source through the high-voltage distribution box, the electric compressor is connected in parallel with the voltage source through the high-voltage distribution box, and the PTC air heater is connected in parallel with the voltage source through the high-voltage distribution box to form a high-voltage system for an electric vehicle. When powering on, the negative main circuit contactor closes, and all loads are pre-charged uniformly. Then the positive main circuit contactor closes to enable each load to reach the state of completing high-voltage power-on. Work enable instructions are sent to each high-voltage component through the vehicle CAN network to control the operation of each high-voltage component. For the resistive load of the PTC air heater, a contactor is designed at the front end of its high-voltage branch, and a closing or opening instruction for the contactor is also sent to the contactor control board through the CAN network to enable or cut off the high voltage input to the PTC air heater, thereby realizing the operation and stop of the PTC air heater. When powering off, a stop work instruction is sent to each high-voltage component through the vehicle CAN network, and then the positive main circuit contactor in the high-voltage power battery system is controlled to open, and the motor controller is controlled to discharge actively. Since all loads are in a parallel relationship, when the motor controller discharges actively, in addition to the capacitor in the motor controller discharging actively, the capacitors in other components will also participate in the discharge, forming the consistency of the high-voltage system. After the active discharge is completed, the main negative contactor in the battery system is controlled to open to complete the high-voltage power-off. The control of power-on and power-off of the entire high-voltage system, and the control of the operation or stop of components, have a simple, clear, and reliable control logic. The copper bar circuit inside the high-voltage distribution box is simple and clear, thus realizing the simplified circuit design, cost reduction, and system stability improvement of the high-voltage system for electric vehicles.
[0031] The above are only embodiments of the present utility model. Common general knowledge such as the specific structures and characteristics in the solution is not described in detail herein. Those of ordinary skill in the art know all the general technical knowledge in the technical field to which the utility model belongs before the application date or the priority date, can know all the prior arts in this field, and have the ability to apply the conventional experimental means before this date. Those of ordinary skill in the art can, under the inspiration given in this application, complete and implement this solution in combination with their own abilities. Some typical well-known structures or well-known methods should not become obstacles for those of ordinary skill in the art to implement this application. It should be noted that for those skilled in the art, without departing from the structure of the present utility model, several deformations and improvements can also be made, which should also be regarded as the protection scope of the present utility model, and these will not affect the implementation effect of the present utility model and the practicability of the patent. The protection scope required by this application should be based on the content of its claims, and the specific implementation manners and the like recorded in the specification can be used to interpret the content of the claims.
Claims
1. A high-voltage system for an electric vehicle, characterized in that: It includes a high-voltage power battery system, a high-voltage distribution box, a control component, and high-voltage components; The high-voltage power battery system includes a voltage source, a pre-charge circuit, and a power supply interface. The voltage source and the pre-charge circuit are in parallel. The positive and negative poles of the voltage source are connected to the input of the power supply interface, and the power supply interface is connected to the high-voltage distribution box; the high-voltage distribution box is connected to the high-voltage components; The control component is used to control the on / off state of the voltage source, the state of the pre-charge circuit, and the power supply state of the high-voltage distribution box.
2. The high-voltage system of an electric vehicle according to claim 1, characterized in that: The pre-charge circuit includes a pre-charge resistor and a pre-charge contactor, and the pre-charge resistor and the pre-charge contactor are in parallel on the positive pole circuit connecting the voltage source and the high-voltage distribution box.
3. The high-voltage system of an electric vehicle according to claim 2, characterized in that: The control component includes a main circuit negative contactor, a main circuit positive contactor, and a main circuit fuse. The main circuit negative contactor is located on the negative circuit connecting the voltage source and the high-voltage distribution box, and the main circuit positive contactor is located on the positive pole circuit connecting the voltage source and the high-voltage distribution box; the main circuit fuse controls the on / off state of the power supply of the voltage source.
4. The high-voltage system of an electric vehicle according to claim 3, characterized in that: The high-voltage components include multiple capacitive loads and multiple resistive loads. The high-voltage distribution box includes multiple capacitive load power supply circuits, multiple resistive load power supply circuits, and corresponding power supply interfaces that are in parallel with the voltage source. The input ends of the multiple capacitive load power supply circuits and the multiple resistive load power supply circuits are connected to the output of the power supply interface of the high-voltage power battery system, and the output ends of the multiple capacitive load power supply circuits and the multiple resistive load power supply circuits are connected to the input of the power supply interface.
5. The high-voltage system of an electric vehicle according to claim 4, wherein: The control component also includes multiple capacitive load fuses and multiple resistive load contactors. The multiple capacitive load contactors are located on each capacitive load power supply circuit and are in parallel with the resistive load contactors.
6. The high-voltage system of an electric vehicle according to claim 5, characterized in that: The high-voltage power battery system also includes a fast charge input interface, and the fast charge input interface is connected to an external fast charge power supply.
7. The high-voltage system of an electric vehicle according to claim 6, characterized in that: The control component also includes a fast charge contactor, and the fast charge contactor is used to control the on / off state of the fast charge input interface.
8. A high-voltage system for an electric vehicle according to claim 7, characterized in that: On the power supply circuit of the voltage source, there are also a battery heating fuse, a battery heating contactor, and a battery heating PTC, and the battery heating fuse, the battery heating contactor, and the battery heating PTC are used to provide protection for the voltage source.
9. The high-voltage system of an electric vehicle according to claim 8, characterized in that: It also includes a communication component, and the communication component is used to provide message commands for the control component.