Insulation detection method based on low frequency impulse signal injection

Abstract

The invention discloses an insulation detection method based on low frequency impulse signal injection. Low frequency impulse signal injection is adopted to detect an insulating performance of a whole vehicle, and a capacitor is adopted to separate a high-voltage current from a detection circuit and separate a direct-current system of the whole vehicle from a low frequency impulse signal, so that an alternating current interference signal brought for an electrical system through high frequency signal injection is reduced, and the defects of reducing the insulating performance of the whole vehicle, incapability in locating an insulation fault point, complex structure, inaccuracy in detection when a positive pole and a negative pole are leaked simultaneously, which are caused by other detection methods, are avoided.

Description

Technical field [0001] The invention relates to the field of electric vehicles, in particular to an insulation monitoring method for electric vehicles. Background technique [0002] Today, when the dual factors of energy shortage and environmental degradation are becoming more and more significant, the development of new energy vehicles with power batteries as the main power is booming. [0003] Compared with conventional cars that use fuel or natural gas as a power source and rarely have high voltage and insulation problems, in order to meet the powerful power required by traction cars, due to the battery itself, the current power battery is connected in series with multiple cells. Meet this demand of automobiles. However, the use of multi-cell series connection will greatly increase the volume of the battery, and the contact area with the body will be greatly increased. The insulation between the body and the battery will be very important, and the electric vehicle uses the powe...

AI Technical Summary

Problems solved by technology

[0014] In order to overcome the deficiencies of the prior art above, the present invention provides an insulation detection method based on low-frequency pulse signal injection, aiming at reducing the AC interference signal brought by the detection method to the electrical system, and avoiding the reduction caused by other detection methods. The insulation performance of the whole vehicle cannot locate the insulation fault point, the structure is complex, the circuit accuracy is high, and the leakage of positive and negative electrodes cannot be accurately detected at the same time.

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