High voltage system electric voltage and insulaiton measurement circuit

Abstract

The present invention provides a measurement device for the voltage of a high voltage system and an insulation resistance, which comprises a high voltage system direct current voltage sampling module, an insulation resistance sampling module, a signal processing module, a high voltage system isolation module, a primary controller module, a CAN bus interface module and a power supply module. The high voltage system direct current voltage sampling module and the insulation resistance sampling module are connected with a positive end of a high voltage direct current system by sampling resistances R36 and R38, and connected with a negative end of the high voltage direct current system by the sampling resistances R37 and R39. The sampling voltage is directly transmitted to the signal processing module through amplifiers U16A and U17B, and voltage signals U1 and U2 are output. The voltage signals U1 and U2 are isolated after connecting with the high voltage system isolation module, and output signals AD1 and AD2 are directly input an AD converter of the primary controller module. Pins164 and 265 of a primary controller are connected with the CAN bus interface module. A power supplying module is connected with a direct current power supply +9V-+18V which can supply the whole system. The present invention can transmit the measured insulation resistance and the direct current voltage to a CAN bus and can be connected to vehicle systems easily.

Description

technical field [0001] The invention relates to a measuring circuit for DC high voltage system voltage and insulation resistance of electric vehicles, hybrid vehicles, railway electric locomotives and electric power systems. Background technique [0002] There are usually high-voltage systems and low-voltage systems in power supply systems such as electric vehicles and railway electric locomotives. Since the high-voltage system provides electric energy for the high-power components of the vehicle, the high-voltage system is mainly composed of power batteries, power converters, motors and other electrical equipment. The voltage of the power battery is usually above 100V, and some are even as high as above 300V. Higher operating voltage systems place higher demands on the insulation performance between the vehicle chassis and the voltage system. Factors such as humidity in the air and aging of the insulating medium will lead to a decrease in the insulation performance betwee...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art that the insulation resistance of the DC high voltage system is measured by the megohmmeter, the measurement accuracy is not high, and the manual operation has potential safety hazards

Images