A current peak detection circuit

Abstract

The invention discloses a current peak value detection circuit, which comprises a current mutual induction module, a sampling resistor, a midpoint bias module, a full swing following isolation module and a micro control unit module. Both ends of the pin, the midpoint bias module is connected to the positive and negative ends of the DC power supply, the full swing follows the input positive pole of the isolation module and is electrically connected to the pin of the sampling resistor, and the full swing follows the input negative pole of the isolation module. The output end of the full-swing following isolation module is connected; the output end of the full-swing following isolation module is connected to the micro control unit module. In the present invention, capacitive coupling is replaced by direct coupling between circuits at all levels to reduce signal transmission delay and deformation; mid-point bias is adopted, so that the collected signal can be normally transmitted in the second half of the cycle when it is powered by a single power supply and meets the requirements of the AD terminal. input requirements while circumventing the complexities of dual-supply operation and the introduced crossover distortion.

Description

technical field [0001] The invention relates to the current detection of an AC power supply, in particular to a current peak detection circuit. Background technique [0002] In the application of AC power supply, it is often necessary to detect the current status to prevent the occurrence of short circuit, open circuit, leakage, etc. In some motor control occasions, the load size of the motor is determined by detecting the current of the motor, and the operation of the motor is adjusted according to the current , to achieve automatic control. [0003] see prior art image 3 , Traditional current detection mostly uses transformers to generate current, current-voltage conversion, AC amplification and shaping, and AD conversion to produce digital signals. Among them, the unique circuit structure of AC amplification and shaping will cause crossover distortion and delay of current signals, which is extremely unfavorable for use in occasions that require accuracy and real-time pe...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a current peak detection circuit for the deficiencies of the prior art, so as to solve the problems of crossover distortion and time delay of the current signal caused by the AC amplification and shaping circuit in the prior art.

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