Insulation impedance detection circuit, detection method thereof and storage medium

Abstract

This invention relates to the field of power electronics testing, and discloses an insulation impedance detection circuit, its detection method, and a storage medium. It employs a single operational amplifier differential amplifier circuit and achieves dual-channel sampling detection, resulting in fewer components, a simpler layout, and higher reliability. First, an uncoupled ideal model is established, and combined with multiple measurement conditions of the insulation impedance detection circuit, the uncoupled ideal relationship of the insulation impedance to ground under ideal conditions is determined. Then, a decoupling calculation is performed by combining the actual sampling voltage under each measurement condition with the uncoupled ideal relationship through a coupling mapping matrix. This considers the influence of coupling factors during the detection process and effectively corrects the ideal sampling voltage in the uncoupled ideal relationship, essentially eliminating the sampling coupling effect introduced by the operational amplifier's common ground in principle. This enables high-precision insulation impedance measurement while controlling circuit cost, maintaining circuit simplicity, and facilitating integration.

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