Isolation detection circuit of direct current components in alternating current

Abstract

The present invention relates to an isolation detection circuit of direct current components in alternating current. The circuit comprises a detection component filtering and transmission circuit, an isolation circuit and a difference amplification circuit. Detection signals are accessed from the input end of the detection component filtering and transmission circuit, the output end of the detection component filtering and transmission circuit is connected with the input end of the isolation circuit, the output end of the isolation circuit is connected with the input end of the difference amplification circuit, and the output end of the difference amplification circuit is the output end of the detection signals; the detection component filtering and transmission circuit is configured to filter alternating current components to retain direct current component; the isolation circuit is configured to output the direct current components, perform voltage division and difference transmission and then perform isolation; and the difference amplification circuit is configured to amplify signals to be detected. According to the embodiment of the invention, the circuit is novel in mode, simple in structure and low in cost, can satisfy demands of direct current component sampling in a lot of alternating current and can be utilized in various electrical devices.

Description

technical field [0001] The invention relates to the technical field of circuit detection, in particular to an isolation detection circuit for DC components in AC power. Background technique [0002] Industrial frequency alternating current (220V / 50Hz), commonly known as mains power, is the most widely used power supply system for domestic electricity and low-power equipment. In addition to power frequency alternating current generated by grid transmission, equipment power supply is generated by inverter circuits in most fields. The inverter circuit is a circuit that converts DC power into AC power. During the conversion process, due to the inconsistency of circuit parameters and errors in control accuracy, in addition to generating AC power, it can also generate weak DC components, such as figure 1 U in 0 . Excessive DC components will cause the primary side of the transformer to be saturated and then short-circuited, which will damage the equipment, and in the parallel s...

AI Technical Summary

Problems solved by technology

[0005] In view of the above analysis, the present invention aims to provide an isolation detection circuit for the DC component in the AC to solve technical problems such as non-isolation of the circuit, limited sampling circuit and parameter matching in the traditional detection scheme.

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