Automobile CAN bus system and its short-circuit control method

Abstract

The invention discloses an automobile controller area network (CAN) bus system and a short circuit control method thereof. The automobile CAN bus system comprises a power twisted pair, a bodywork twisted pair, an engine electronic control unit (ECU) and a bodywork controller; the power twisted pair is electrically connected with the bodywork twisted pair; the engine ECU is electrically connected with the power twisted pair; and the bodywork controller is electrically connected with the bodywork twisted pair. The automobile CAN bus system further comprises a voltage detecting unit and an automatic switch unit; the voltage detecting unit is respectively and electrically connected with the bodywork twisted pair and the bodywork controller; the automatic switch unit is respectively and electrically connected with the power twisted pair and the bodywork controller; the voltage detecting unit is used for collecting the voltage values of the bodywork twisted pair and outputting to the bodywork controller; and the automatic switch unit is used for receiving the control signals of the bodywork controller and controlling the connecting and breaking of the power twisted pair and the bodywork twisted pair. The automobile CAN bus system and the short circuit control method are capable of reducing the probability of the abnormal deceleration of the engine caused by the twisted pair short circuit.

Description

Technical field [0001] The invention relates to automobile technology, in particular to an automobile CAN bus system and a short circuit control method thereof. Background technique [0002] At present, the vast majority of cars have adopted the controller area network CAN bus technology. CAN bus technology connects various controllers (such as instrumentation, body controller, engine ECU, ABS, etc.) on the car through twisted pair wires for interconnection communication. [0003] Because each controller is distributed in different positions of the car, for example, the instrument and the body controller are arranged in the front section of the car body, and the engine ECU and ABS are arranged in the power part of the car, resulting in a long twisted pair connecting the controllers. The car will vibrate when driving. If the twisted pair is not firmly fixed, it will rub against the car body structure due to the vibration. Long-term friction will wear the insulation layer of the twi...

AI Technical Summary

Problems solved by technology

[0003] Since each controller is distributed in different positions of the car, for example, the instrument and body controller are arranged in the front section of the car body, and the engine ECU and ABS are arranged in the power part of the car, which results in a long twisted pair connecting the controllers.

The car will vibrate during driving. If the twisted pair is not fixed firmly, it will cause friction with the structure of the car body due to the vibration. Long-term friction will wear out the insulation layer of the twisted pair and cause a short circuit of the twisted pair. , the various controllers of the car will not be able to communicate normally, and most of the functions on the car will be paralyzed

Among them, the engine ECU will automatically limit the torque if it cannot receive the message signal normally due to the short circuit of the twisted pair, which will cause the car to decelerate sharply.

Uncontrolled deceleration of cars poses a great safety hazard

[0004] The disadvantage of the existing technology is that any short circuit on the twisted pair will cause the engine ECU to control the engine to decelerate abnormally, thus causing potential safety hazards

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