Vehicle and insulation monitoring circuit for vehicle battery

Abstract

The embodiment of the invention provides a vehicle and an insulation monitoring circuit for a vehicle battery. The insulation monitoring circuit obtains power supply from the vehicle battery and comprises a voltage-frequency conversion circuit, an RC series circuit, a first peak value sampling circuit and an alarm triggering module. The voltage-frequency conversion circuit outputs a low-frequency pulse signal and injects the low-frequency pulse signal into a high-voltage system connected with a vehicle battery through the RC series circuit; the first peak value sampling circuit is used for sampling a voltage signal at the rear end of a resistor in the RC series circuit and feeding back the voltage signal to the voltage-frequency conversion circuit, so that an output low-frequency pulse signal adapts to a vehicle battery; and the alarm trigger module processes a voltage signal at the rear end of the resistor in the RC series circuit and outputs an alarm trigger signal. The whole insulation monitoring process can not be controlled by a BMS of the vehicle, real-time insulation monitoring can be carried out as long as the vehicle battery is complete, meanwhile, the low-frequency pulse signals are output through a closed loop, self-adaption to capacitance between a high-voltage loop and a low-voltage loop of the vehicle battery can be achieved, and therefore stable and reliable insulation monitoring can be achieved.

Description

technical field [0001] The embodiments of the present application relate to the technical field of circuits, and more specifically relate to a vehicle and an insulation monitoring circuit for a vehicle battery. Background technique [0002] With the continuous development of new energy vehicles, the safety performance of vehicles is getting more and more attention. Since the working voltage of the vehicle power battery is as high as 400 to 1000V, which is far higher than the safe voltage of the human body, once a leakage accident occurs, the lives of the drivers and passengers will be endangered. Therefore, it is necessary to monitor the insulation status of the vehicle power battery in real time. [0003] In related technologies, the insulation monitoring mainly adopts the balanced bridge method, which mainly controls the closing of corresponding bridge arms in the balanced bridge by software to obtain sampling values ​​at each point, and then calculates the insulation valu...

AI Technical Summary

Problems solved by technology

However, when the whole vehicle is dormant, the BMS of the vehicle is not working and cannot send a control signal to control the closing of the corresponding bridge arm, so it is impossible to monitor the insulation status of the vehicle battery in real time

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