Double coil various current control method for vacuum breaker permanent magnetism mechanism

Abstract

Disclosed is a current varying control method of double-coil of permanent mechanisms of vacuum circuit breakers. In closing process, a trip coil is reversely galvanized to offset a part of permanent magnet retaining force, to reduce closing action current, simultaneously adjust the current of a closing coil, and reduce iron core kinetic energy on the premise of ensuring instantaneous closing speed. In switching off time, the trip coil is directly galvanized, the closing coil is reversely galvanized or the trip coil is directly galvanized and the closing coil is directly galvanized. Voltage and current of the trip coil and the closing coil are sampled by a coil current measuring module, and collected data is fed back to a central control module. A central treatment module calculates rate of current change in current coils and adjusts current value in the trip coil according to calculated result. The invention adjusts current amplitude in coils by sampling feedback of current and voltage of the trip coil and the closing coil of a permanent mechanism, and enables the operating characteristic of the permanent mechanism and the spring load characteristic of the circuit breaker to realize ideal engagement.

Description

technical field [0001] The invention belongs to the field of electronic applications, and in particular relates to a double-coil variable current control method of a permanent magnet mechanism of a vacuum circuit breaker. Background technique [0002] The bistable permanent magnet mechanism is a new type of operating mechanism designed for vacuum circuit breakers. It has attracted widespread attention because of its high reliability and small dispersion of opening and closing times, and it has been widely used in the medium-voltage field. Its main action features are: when the opening or closing signal is sent out, the power supply supplies power to the opening coil or closing coil, and the electromagnetic force generated by the coil overcomes the reaction force and permanent magnetic holding force, drives the iron core and then drives the circuit breaker contacts Complete opening and closing operations. After the action is completed, the permanent magnet provides the holdi...

AI Technical Summary

Problems solved by technology

High-voltage circuit breakers require faster action speeds. Under the condition of a certain number of ampere-turns, in order to properly reduce the current, the number of turns can only be increased. The more turns of the coil, the greater the inductance, and the current rises to the action requirement. The longer the current time, the longer the action time will be, which will increase the dispersion of opening and closing time, and cannot meet the requirements of synchronous closing

[0004] The existing mechanism design generally focuses on the rationality of the structure so that the characteristics of the permanent magnet mechanism can be well matched with the characteristics of the vacuum circuit breaker. However, the traditional single-coil control strategy obviously cannot overcome the excessive current, long operating time, rigid The defect of insufficient sub-speed

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