CN104118372A - Hybrid electric vehicle CAN network system - Google Patents

Abstract

Aiming at the problem that the diagnostic equipment in the CAN network system of the hybrid electric vehicle in the prior art diagnoses each node connected with the CAN of the vehicle through the gateway, the design of the gateway is complicated and the diagnosis process is increased, the present invention provides a CAN network system of the hybrid electric vehicle , including body CAN, power CAN, hybrid CAN and diagnostic interface, the vehicle body controller is used as a gateway for information exchange between the body CAN and power CAN, and the hybrid electronic control module is used as a gateway between the power CAN and hybrid CAN information exchange; the body CAN includes a body CAN bus and a first group of nodes connected to the body CAN bus, the power CAN includes a power CAN bus and a second group of nodes connected to the power CAN bus, and the hybrid CAN includes a hybrid CAN bus and a third group of nodes connected to the hybrid CAN bus; the diagnostic interface is directly connected to the vehicle body CAN, power CAN and hybrid CAN; the system simplifies the complexity of gateway design and the diagnostic process.

Description

A Hybrid Vehicle CAN Network System

technical field

The invention relates to the field of automobile local area network, in particular to a CAN network system of a hybrid electric vehicle.

Background technique

With the rapid development of electronic information technology and network technology, automobiles are no longer a simple combination of mechanical parts, and their electronic degree is getting higher and higher; in order to reduce costs and simplify wire-speed connections, various automobile manufacturers have adopted Various bus control technologies can achieve the purpose of data exchange between automotive electronic control modules. CAN bus is one of the most important bus protocols. Because of its high transmission rate, low cost and reliable error handling and error detection mechanism, etc., Widely used in the automotive industry.

A hybrid electric vehicle CAN network system is currently provided, which is composed of a traditional power subnet, a hybrid subnet and a calibration diagnosis subnet. The three-way communication subnet is connected to several nodes respectively, and the traditional power subnet , the hybrid subnet and the calibration diagnosis subnet exchange information through the vehicle controller, that is, the vehicle controller is a gateway, and the diagnostic equipment sends a diagnosis request signal to the vehicle controller through the calibration diagnosis subnet, and the vehicle controller The diagnostic request signal is sent to each node, and each node receives the diagnostic request signal and then feeds back the error information and fault sequence to the diagnostic equipment through the vehicle controller to complete the node diagnosis. However, the existing diagnostic equipment uses the gateway to indirectly diagnose each node connected to the CAN bus of the automobile, and has the following problems: one, because the gateway itself is a node and integrates a communication module as a gateway, it is relatively complicated. If the gateway is used as a diagnostic The signal transponder will complicate the design of the gateway; second, the diagnostic process will be increased due to the need for the gateway to transmit diagnostic signals.

Contents of the invention

In order to solve the problem that the diagnostic equipment in the CAN network system of the hybrid electric vehicle in the prior art uses the gateway to indirectly diagnose each node connected to the CAN bus of the vehicle, the design of the gateway will be complicated and the diagnosis process will be increased.

On the one hand, the embodiment of the present invention provides a CAN network system of a hybrid electric vehicle, including a vehicle body CAN, a power CAN, a hybrid CAN and a diagnostic interface,

The vehicle body CAN and the power CAN use the body controller as a gateway to perform information exchange, and the power CAN and the hybrid CAN use a hybrid electronic control module as a gateway to perform information exchange;

The body CAN includes a body CAN bus and a first group of nodes connected to the body CAN bus, the power CAN includes a power CAN bus and a second group of nodes connected to the power CAN bus, and the hybrid CAN includes a hybrid a CAN bus and a third group of nodes connected to said hybrid CAN bus;

The diagnostic interface is respectively connected to the buses of the vehicle body CAN, power CAN and hybrid CAN.

In the CAN network system of the hybrid electric vehicle of the present invention, the diagnostic interface is connected with the vehicle body CAN bus, the power CAN bus and the hybrid CAN bus. Fault diagnosis, in this way, relative to the existing indirect diagnosis nodes through the gateway, the direct diagnosis of each node does not need to pass through and utilize the gateway, thereby reducing the diagnosis process and reducing the design complexity of the gateway; in addition, the hybrid vehicle CAN disclosed by the present invention The network system adopts three CAN buses. Compared with the two CAN buses in the prior art, each CAN bus has fewer nodes connected, thereby reducing the load on a single CAN bus and increasing the service life of the CAN bus.

Further, in the hybrid vehicle CAN network system of the present invention, the CAN bus of the vehicle body is a CAN bus with a first transmission speed, and messages with a third-level danger level are transmitted on the CAN bus of the vehicle body;

The power CAN bus is a CAN bus with a second transmission speed, and messages with a second level of danger are transmitted on the power CAN bus;

The hybrid CAN bus is a CAN bus with a third transmission speed, and messages whose risk level is the first level are transmitted on the hybrid CAN bus;

Wherein, the first transmission speed is less than the second transmission speed, and the second transmission speed is less than or equal to the third transmission speed; the third level is less than the second level, and the second level is less than the first level.

Further, in the hybrid electric vehicle CAN network system of the present invention, the number of messages transmitted at the same time on the CAN bus of the vehicle body meets the first threshold; the number of messages transmitted at the same time on the power CAN bus meets the second threshold. Threshold; the number of messages transmitted at the same time on the hybrid CAN bus meets the third threshold;

Wherein, the first threshold is greater than the second threshold, and the second threshold is less than or equal to the third threshold.

Further, in the hybrid vehicle CAN network system according to the present invention, the vehicle body controller includes a packaging unit, which is used to package the messages received from the vehicle body CAN bus and/or the power CAN bus issue;

The hybrid electronic control module includes a control algorithm unit, which is used to add predetermined messages received from the vehicle body power CAN bus and/or hybrid CAN bus into the control algorithm for processing and send out.

Further, in the hybrid electric vehicle CAN network system according to the present invention, a first matching component is provided between each node of the first group of nodes and the vehicle body CAN bus, and the first matching component includes a first A damping element and a second damping element, the first damping element is connected between each node of the first group of nodes and the vehicle body CAN_H bus, and the second damping element is connected between each of the first group of nodes Between the node and the body CAN_L bus;

In the second group of nodes, the two nodes whose physical positions are farthest apart and the power CAN bus are respectively provided with a second matching assembly, and the second matching assembly includes a fourth damping element, a fifth damping element and a fourth damping element. A charge storage element, wherein the fourth damping element and the fifth damping element are connected in series between the power CAN_H bus and the power CAN_L bus, and one end of the first charge storage element is connected between the fourth damping element and the power CAN_L bus. Between the fifth damping elements, the other end is grounded;

A second matching assembly is provided between the two nodes whose physical positions are farthest apart in the third group of nodes and the hybrid CAN bus, and the second matching assembly includes a fourth damping element, a fifth damping element and a first A charge storage element, wherein the fourth damping element and the fifth damping element are connected in series between the hybrid CAN_H bus and the hybrid CAN_L bus, and one end of the first charge storage element is connected between the fourth damping element and the Between the fifth damping element, the other end is grounded.

Further, in the hybrid electric vehicle CAN network system of the present invention, a protection circuit is provided between each node of the third group of nodes and the hybrid CAN bus;

The protection circuit includes an optocoupler isolation element, a third damping element and a second charge storage element, the optocoupler isolation element is connected between each node of the third group of nodes and the hybrid CAN bus, the The third damping element and the second charge storage element are connected in series between the hybrid CAN shield bus and the ground.

Further, in the hybrid vehicle CAN network system of the present invention, the body CAN bus adopts a fault-tolerant CAN bus, and the power CAN bus and hybrid CAN bus adopt a high-speed CAN bus.

Further, in the hybrid electric vehicle CAN network system of the present invention, the first group of nodes includes an instrument module, a reversing radar module, an air-conditioning module, a body controller, a speaker module and a seat memory module;

The second group of nodes includes engine electronic control module, body controller, gearbox electronic control module, brake electronic control module, traction electronic control module, power steering module, airbag module, hybrid electric control module and tire pressure module ;

The third group of nodes includes a hybrid electronic control module, a front motor electronic control module, a rear motor electronic control module, a battery management module, a power conversion module and a charging module.

Furthermore, in the hybrid vehicle CAN network system of the present invention, the diagnostic interface is a diagnostic interface conforming to international general standards.

Description of drawings

Fig. 1 is a schematic diagram of a hybrid electric vehicle CAN network system provided by an embodiment of the present invention;

2 is a schematic diagram of the connection between the first matching component and the first group of nodes and the vehicle body CAN bus in the hybrid electric vehicle CAN network system provided by the embodiment of the present invention;

3 is a schematic diagram of the connection between the second matching component and the second group of nodes and the power CAN bus in the hybrid electric vehicle CAN network system provided by the embodiment of the present invention;

Fig. 4 is a schematic diagram of the connection between the protection circuit, the third group of nodes and the hybrid CAN bus in the CAN network system of the hybrid electric vehicle provided by the embodiment of the present invention.

Among them, 1. Body CAN bus; 2. Power CAN bus; 3. Hybrid CAN bus; 4. Diagnostic interface; 5. The first group of nodes; 51. Instrument module; 52. Reversing radar module; 53. Air conditioning module; Speaker module; 55. Seat memory module; 6. The second group of nodes; 61. Traction electronic control module; 62. Brake electronic control module; 63. Transmission electronic control module; 64. Engine electronic control module; 7. The first Three groups of nodes; 71. Power conversion module; 72. Motor electronic control module; 73. Battery management module; 74. Charging module; Electronic control module.

Detailed ways

In order to make the technical problems, technical solutions and beneficial effects solved by the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

In the present invention, the English full name of the abbreviation "CAN" is "Controller Area Network", and the Chinese meaning is "Controller Local Area Network"; the English full name of the abbreviation "BCAN" is "Body Controller Area Network", and the Chinese meaning is "Body Controller Area Network". "; the English full name of the abbreviation "PCAN" is "Power Controller Area Network", which means "power controller area network" in Chinese; the full English name of the abbreviation "HCAN" is "Hybrid Controller Area Network", which means "hybrid controller area network" in Chinese The English full name of the abbreviation "CAN_H" is "Controller Area Network_High", which means "high controller local area network" in Chinese; the full English name of the abbreviation "CAN_L" is "ControllerArea Network_Low", which means "low controller local area network" in Chinese The Chinese meaning of the unit "Kb/s" is "1 kilobyte per second"; the Chinese meaning of the English "Shield" is "shielding wire"; the full English name of the abbreviation "UDS" is "Unified diagnostic services", The Chinese meaning is "unified diagnostic service"; the English full name of the abbreviation "SAE" is "Society of Automotive Engineers", and the Chinese meaning is "American Society of Motor Vehicle Engineers"

The hybrid vehicle CAN network system of the present invention is mainly used to realize the transmission and interaction of the messages provided by each node on the hybrid vehicle, and then realize the intelligent management of each node; wherein the gateway is used to transmit information on different CAN buses The message is converted to realize the interconnection of different networks; the CAN bus includes CAN_H bus, CAN_L bus and CAN_Shield bus, wherein the messages required by the nodes connected to the CAN bus are transmitted through the CAN bus.

The present invention is further described by way of examples below.

This embodiment is used to illustrate the hybrid electric vehicle CAN network system disclosed by the present invention, as shown in Fig. 1, Fig. 2, Fig. 3 and Fig. 4, described hybrid electric vehicle CAN network system comprises vehicle body CAN, power CAN, hybrid CAN and Diagnosis interface 4, information exchange between the vehicle body CAN and the power CAN with the vehicle body controller 10 as the gateway, information exchange between the power CAN and the hybrid CAN with the hybrid electronic control module 11 as the gateway; the vehicle body CAN Including a body CAN bus 1 and a first group of nodes 5 connected to the body CAN bus 1, the power CAN includes a power CAN bus 2 and a second group of nodes 6 connected to the power CAN bus 2, and the hybrid CAN includes a hybrid CAN bus 3 and a third group of nodes 7 connected to the hybrid CAN bus 3; the diagnostic interface 4 is respectively connected to the vehicle body CAN bus 1, the power CAN bus 2 and the hybrid CAN bus 3.

The diagnostic interface 4 is connected to the vehicle body CAN bus 1, the power CAN bus 2 and the hybrid CAN bus 3. When it is necessary to diagnose each node, the diagnostic equipment directly performs fault diagnosis on each node connected to the CAN bus through the diagnostic interface 4 (that is, the diagnostic interface is connected to the CAN bus). The nodes are directly connected by hard wires, without intermediate components), so that compared with the existing indirect diagnosis nodes through the gateway, the direct diagnosis of each node does not need to go through and use the gateway, which reduces the diagnosis process and reduces the design complexity of the gateway In addition, the hybrid vehicle CAN network system disclosed by the present invention adopts three CAN buses. Compared with the two CAN buses of the prior art, the nodes connected on each CAN bus are less, and then the load on the single CAN bus is reduced. , Increase the service life of the CAN bus.

Further, the diagnostic interface 4 is a diagnostic interface conforming to international general standards, which can satisfy the versatility and scalability of hardware and software.

Further, as a preferred embodiment, the vehicle body CAN bus 1 transmits messages with a risk level of the third level, and the messages transmitted by the vehicle body CAN bus 1 are the messages transmitted by the first group of nodes 5 to the vehicle body CAN bus 1 , the first group of nodes 5 is mainly for some nodes related to entertainment and comfort; on the power CAN bus 2, the message with the second level of danger is transmitted, and the message transmitted by the power CAN bus 2 is transmitted to the second group of nodes 6 For the messages on the power CAN bus 2, the second group of nodes 6 are mainly nodes related to automobile braking; on the mixed CAN bus 3, the messages whose risk level is the first level are transmitted, and the messages transmitted by the mixed CAN bus 3 are The third group of nodes 7 transmits the message on the hybrid CAN bus 3, and the third group of nodes 7 is mainly some nodes that provide vehicle power. The risk level of the message is determined according to the degree of correlation between the message and the vehicle safety, the third level is smaller than the second level, and the second level is smaller than the first level; according to the risk of the message carried by the node Specifically, the nodes are divided into three categories, and each category is connected to a different CAN bus, which is convenient for network management.

Further, as a preferred embodiment, the body CAN bus 1 is a CAN bus with a first transmission speed, the power CAN bus 2 is a CAN bus with a second transmission speed, and the hybrid CAN bus 3 is a CAN bus with a second transmission speed. The CAN bus of the third transmission speed; wherein, since the first group of nodes 5 connected with the CAN bus 1 of the vehicle body are nodes related to comfort and entertainment, the requirements for the transmission speed of the message are not high, and a smaller transmission speed can be selected. CAN bus, the first transmission speed described in this embodiment is 125Kb/s, of course also can do adaptive adjustment according to the actual situation; It is a node related to dynamic and power supply, so the request for the transmission speed of the message is relatively high. The second transmission speed in this embodiment is equal to the third transmission speed, both of which are 500Kb/s. Of course, it can also be done according to the actual situation. Adaptive adjustment, such as adjusting the third transmission speed to be slightly greater than the second transmission speed. Connect the nodes with a lower risk level of messages to the CAN bus with a lower transmission speed, and connect the nodes with a higher risk level of messages to the CAN bus with a higher transmission speed; this not only realizes hierarchical management of the network, It can also ensure that messages with a higher risk level can be delivered in time, and avoid traffic accidents caused by message delays.

Further, since the messages carried by some nodes on the car have a high degree of correlation with the safety of the car, they need to be transmitted in time, in order to prevent safety accidents caused by message transmission delays, as a preferred embodiment, the vehicle body CAN bus 1 of the present invention The number of messages transmitted at the same time must meet the first threshold, where the first threshold is 50% of the maximum number of messages that can be transmitted by the body CAN bus 1 itself, and the number of messages transmitted on the body CAN bus 1 at the same time Less than or equal to 50% of the maximum number of messages that can be transmitted by itself means that the number of messages transmitted on the vehicle body CAN bus 1 at the same time meets the first threshold. The number of messages transmitted on the power CAN bus 2 at the same time must meet the second threshold, where the second threshold is 30% of the maximum number of messages that the power CAN bus 2 itself can transmit, and the number of messages transmitted on the power CAN bus 2 at the same time If the number of messages is less than or equal to 30% of the maximum number of messages that can be transmitted by itself, the number of messages transmitted on the power CAN bus 2 at the same time meets the second threshold. The number of messages transmitted on the hybrid CAN bus 3 at the same time must meet the third threshold, where the third threshold is 30% of the maximum number of messages that the hybrid CAN bus 3 can transmit itself, and the number of messages transmitted on the hybrid CAN bus 3 at the same time If the number of messages is less than or equal to 30% of the maximum number of messages that can be transmitted by itself, the number of messages transmitted on the hybrid CAN bus 3 at the same time meets the third threshold. In addition, the first threshold, the second threshold and the third threshold can be adaptively adjusted.

By limiting the number of messages transmitted at the same time on each CAN bus, it is ensured that when the messages are transmitted on the CAN bus, the message transmission delay will not be caused by the excessive number of messages transmitted at the same time, thereby avoiding the transmission of messages at the same time The number of reasons caused car accidents.

Further, as a preferred embodiment, the vehicle body controller 10 includes a packaging unit (not shown in the figure), the packaging unit is used to receive data from the vehicle body CAN bus 1 and/or the power CAN bus 2 The message is packaged and sent out; for example, when the body controller 10 receives a handbrake signal from the power CAN bus 2, the body controller 10 directly packs the signal and other signals to be forwarded into a frame message and sends it to the power CAN bus 2 In general, the vehicle body controller 10 only performs simple package sending, which can simplify the complexity of the vehicle body controller 10. The body controller 10 itself is also a node on the body CAN and the power CAN, that is, the body controller 10 belongs to the first group of nodes 5 and the second group of nodes 6 at the same time.

The hybrid electronic control module 11 includes a control algorithm unit (not shown in the figure), and the control algorithm unit is used to add predetermined messages received from the vehicle body power CAN bus 2 and/or the hybrid CAN bus 3 to the control Emitted after algorithm processing. For example, after the hybrid electronic control module 11 receives the battery state-of-charge signal from the hybrid CAN bus 3, it will add the signal to the control algorithm, perform nonlinear offset processing on the signal to obtain the corresponding battery state-of-charge signal package Send it to the power CAN bus 2; usually because the power of the battery cannot really reach 0%, if it is discharged to 0%, it will cause great damage to the battery. When the power of the battery reaches a certain level, such as 10%, the car cannot Use the battery, but it is necessary to display the battery state of charge signal on the instrument, but if the instrument shows that the battery has 10% power left, the driver will think that the battery still has power and the vehicle cannot be driven because of other reasons, so the hybrid electronic control The module 11 will output 10% of the electric quantity of the battery through non-linear offset processing to obtain 0%, which can avoid the driver's misunderstanding; the related control algorithm added in the hybrid electronic control module 11 can also be processed in other ways, such as linear offset, etc.; in addition, the related algorithm is added to the hybrid electronic control module 11, and no related algorithm is added to other nodes, so that the design of each node of the vehicle is relatively simplified. Scheduled messages are some messages that need to be processed by algorithms. The hybrid electronic control module 11 itself is also a node on the power CAN and the hybrid CAN, that is, the hybrid electronic control module 11 belongs to the second group of nodes 6 and the third group of nodes 7 at the same time.

The first group of nodes 5 includes an instrument module 51, a reversing radar module 52, an air-conditioning module 53, a speaker module 54 and a seat memory module 55; the second group of nodes 6 includes an engine electronic control module 64, a gearbox electronic control module 63. Braking electronic control module 62, traction electronic control module 61, power steering module (not shown in the figure), airbag module (not shown in the figure) and tire pressure module (not shown in the figure); the The third group of nodes 7 includes a motor electronic control module 72 , a battery management module 73 , a power conversion module 71 and a charging module 74 ; the motor electronic control module 72 includes a front motor electronic control module and a rear motor electronic control module.

Further, in order to ensure the normal operation and stability of each CAN bus, as shown in Figure 2, as a preferred embodiment, the present invention is provided with a second a matching assembly, the first matching assembly includes a first damping element R1 and a second damping element R2, the first damping element R1 is connected between each node of the first group of nodes 5 and the vehicle body CAN_H bus, The second damping element R2 is connected between each node of the first group of nodes 5 and the vehicle body CAN_L bus. The values of the first damping element R1 and the second damping element R2 are equal, about 500 ohms. Connectors, gateway transceiver characteristics, etc., generally about 120 ohms; the selection of the size of the first matching component of each node in the first group of nodes 5 adopts a simple and quick calculation method: that is, the first group of nodes 5 After connecting to the network, make the damping element value of the matching components on the CAN bus of the whole body not less than 100 ohms, about 120 ohms. This can improve the electromagnetic compatibility of the network; if there are four first group of nodes 5 connected to the CAN bus of the vehicle body, using the above method, the size of each damping element can be roughly calculated to be about 500 ohms, and the final practical value is about 500 ohms. The influence of electromagnetic compatibility should be considered.

Further, as a preferred embodiment, as shown in FIG. 3 , the two nodes whose physical positions are farthest apart in the second group of nodes 6 and the power CAN bus 2 are respectively provided with a second matching component. The two matching components include a fourth damping element R4, a fifth damping element R5 and a first charge storage element C1, wherein the fourth damping element R4 and the fifth damping element R5 are connected in series between the CAN_H bus and the CAN_L bus, the second One end of a charge storage element C1 is connected between the fourth damping element R4 and the fifth damping element R5, and the other end is grounded.

A second matching assembly is provided between the two nodes whose physical positions are farthest apart in the third group of nodes 7 and the hybrid CAN bus 3, and the second matching assembly includes a fourth damping element R4, a fifth damping element R5 and a fourth damping element R5. A charge storage element C1, wherein the fourth damping element R4 and the fifth damping element R5 are connected in series between the CAN_H bus and the CAN_L bus, and one end of the first charge storage element C1 is connected to the fourth damping element R4 and the fifth damping element Between components R5, the other end is grounded.

Further, as a preferred embodiment, as shown in Figure 4, a protection circuit is provided between each node of the third group of nodes 7 and the hybrid CAN bus 3; the protection circuit includes an optocoupler isolation element 9, a second Three damping elements R3 and a second charge storage element C2, the optocoupler isolation element 9 is connected between each node of the third group of nodes 7 and the hybrid CAN bus 3, the damping element R3 and the second The charge storage element C2 is connected in series between the hybrid CAN Shield bus and the ground. Wherein the optocoupler isolation element 9 is specifically connected with the CAN_H bus and the CAN_L bus of the hybrid CAN bus 3, and is connected with the control section 8 of each node of the third group of nodes 7. When the data processed by the control section 8 is output, it first passes through the optocoupler The isolation element 9 performs conversion, and the converted data forms a message and transmits it to the hybrid CAN bus 3. External interference is filtered by a filter formed by connecting the third damping element R3 and the second charge storage element C2 in series, and the finally obtained message Good stability. The third damping element R3 is 1 ohm, and the second charge storage element C2 is 0.68 microfarads. Of course, the values of the third damping element R3 and the second charge storage element C2 can be adaptively adjusted with reference to SAE standards.

As a preferred embodiment, in the present invention, the vehicle body CAN bus 1 samples a fault-tolerant CAN bus, and the power CAN bus 2 and the hybrid CAN bus 3 adopt a high-speed CAN bus. Communication function, high-speed CAN bus has better real-time performance.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. within range.

In addition, it should be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable way if there is no contradiction. The combination method will not be described separately. In addition, various combinations of different embodiments of the present invention can also be combined arbitrarily, as long as they do not violate the idea of the present invention, they should also be regarded as the disclosed content of the present invention.

Claims (9)

1. A hybrid electric vehicle CAN network system is characterized in that, comprising vehicle body CAN, power CAN, hybrid CAN and diagnostic interface, The vehicle body CAN and the power CAN use the body controller as a gateway to perform information exchange, and the power CAN and the hybrid CAN use a hybrid electronic control module as a gateway to perform information exchange; The body CAN includes a body CAN bus and a first group of nodes connected to the body CAN bus, the power CAN includes a power CAN bus and a second group of nodes connected to the power CAN bus, and the hybrid CAN includes a hybrid a CAN bus and a third group of nodes connected to said hybrid CAN bus; The diagnostic interface is respectively connected to the body CAN bus, the power CAN bus and the hybrid CAN bus. 2. The hybrid electric vehicle CAN network system according to claim 1, wherein the CAN bus of the vehicle body is a CAN bus with a first transmission speed, and the transmission risk level on the CAN bus of the vehicle body is the third grade. message; The power CAN bus is a CAN bus with a second transmission speed, and messages with a second level of danger are transmitted on the power CAN bus; The hybrid CAN bus is a CAN bus with a third transmission speed, and messages whose risk level is the first level are transmitted on the hybrid CAN bus; Wherein, the first transmission speed is less than the second transmission speed, and the second transmission speed is less than or equal to the third transmission speed; the third level is less than the second level, and the second level is less than the first level. 3. The hybrid electric vehicle CAN network system according to claim 1 or 2, wherein the number of messages transmitted at the same time on the vehicle body CAN bus meets the first threshold; The number of messages meets the second threshold; the number of messages transmitted on the hybrid CAN bus at the same time meets the third threshold; Wherein, the first threshold is greater than the second threshold, and the second threshold is less than or equal to the third threshold. 4. The hybrid electric vehicle CAN network system according to claim 1 or 2, characterized in that, the vehicle body controller includes a packaging unit, and the packaging unit is used to receive data from the vehicle body CAN bus and/or the power CAN bus. The received message is packaged and sent out; The hybrid electronic control module includes a control algorithm unit, which is used to add predetermined messages received from the vehicle body power CAN bus and/or hybrid CAN bus into the control algorithm for processing and send out. 5. The hybrid electric vehicle CAN network system according to claim 1 or 2, wherein a first matching assembly is provided between each node of the first group of nodes and the vehicle body CAN bus, and the second A matching assembly includes a first damping element and a second damping element, the first damping element is connected between each node of the first group of nodes and the vehicle body CAN_H bus, the second damping element is connected between the first Between each node of a group of nodes and the body CAN_L bus; In the second group of nodes, the two nodes whose physical positions are farthest apart and the power CAN bus are respectively provided with a second matching assembly, and the second matching assembly includes a fourth damping element, a fifth damping element and a fourth damping element. A charge storage element, wherein the fourth damping element and the fifth damping element are connected in series between the power CAN_H bus and the power CAN_L bus, and one end of the first charge storage element is connected between the fourth damping element and the power CAN_L bus. Between the fifth damping elements, the other end is grounded; In the third group of nodes, the two nodes whose physical positions are farthest apart and the hybrid CAN bus are respectively provided with a second matching assembly, and the second matching assembly includes a fourth damping element, a fifth damping element and a fourth damping element. A charge storage element, wherein the fourth damping element and the fifth damping element are connected in series between the hybrid CAN_H bus and the hybrid CAN_L bus, and one end of the first charge storage element is connected between the fourth damping element and the hybrid CAN_L bus. Between the fifth damping elements, the other end is grounded. 6. according to claim 1 and 2 described hybrid vehicle CAN network systems, it is characterized in that, a protection circuit is set between each node of the third group of nodes and the hybrid CAN bus; The protection circuit includes an optocoupler isolation element, a third damping element and a second charge storage element, the optocoupler isolation element is connected between each node of the third group of nodes and the hybrid CAN bus, the The third damping element and the second charge storage element are connected in series between the hybrid CAN shield bus and the ground. 7. The hybrid electric vehicle CAN network system according to claim 1 or 2, wherein the vehicle body CAN bus adopts a fault-tolerant CAN bus, and the power CAN bus and hybrid CAN bus adopt a high-speed CAN bus. 8. The hybrid electric vehicle CAN network system according to claim 1, wherein the first group of nodes comprises an instrument module, a reversing radar module, an air-conditioning module, a vehicle body controller, a sound box module and a seat memory module; The second group of nodes includes engine electronic control module, body controller, gearbox electronic control module, brake electronic control module, traction electronic control module, power steering module, airbag module, hybrid electric control module and tire pressure module ; The third group of nodes includes a hybrid electronic control module, a front motor electronic control module, a rear motor electronic control module, a battery management module, a power conversion module and a charging module. 9. The hybrid electric vehicle CAN network system according to claim 1, wherein the diagnostic interface is a diagnostic interface conforming to international general standards.