Power supply circuit of intelligent release

Abstract

The invention relates to a power supply circuit of an intelligent release, which is powered by a self-generation power supply circuit. The power supply circuit comprises a current transformer, a current detection conditioning unit connected with the current transformer, a central control unit connected with the current detection conditioning unit, a releasing driving circuit connected with the central control unit, and a releasing execution unit connected with the releasing driving circuit. A parameter control input end of the central control unit is connected with a setting value input unit, and a communication data end of the central control unit is connected with a serial communication interface for connecting an upper computer. During operation, a singlechip performs AD conversion on a voltage signal processed by the current transformer through the current detection conditioning unit; according to a sampling value, logic operation and processing are performed, and logic level signals according with preset protection characteristics are output after the operation result and a setting value are compared; and the signals pass through the releasing driving circuit and are sent to a magnetic flux converter in the releasing execution unit to enable a breaker to trip and cut off the circuit.

Description

technical field [0001] The invention relates to a power circuit of an intelligent release. Background technique [0002] Molded case circuit breaker is an important electrical switch in low-voltage distribution lines and motor control and protection. When faults such as short circuit, overcurrent and undervoltage occur in the circuit, it can automatically cut off the circuit to protect the circuit and equipment. In order to obtain different protection characteristics, traditional circuit breakers need to be equipped with different release units. With the continuous expansion of the scale and grade of the power consumption system, it is more and more difficult for the traditional trip unit to meet the requirements of reliability, accuracy and real-time performance of the system. And for the circuit breaker, it mainly bears the electrodynamic shock and thermal shock of the fault current, that is, the dynamic stability and thermal stability of the circuit breaker. Traditiona...

AI Technical Summary

Problems solved by technology

[0004] 1) Since the power source energy comes from the current transformer, the current in the grid circuit is not enough to supply power when the current is small

2) When the current of the grid circuit rises slowly, the voltage of the self-powered power supply also rises slowly, which is not conducive to the normal operation of the intelligent control circuit

3) Due to the large input current range of the current transformer, some components of the power supply circuit are seriously heated, which affects the normal operation of the system

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