矿用异步电动机分级离散变频软启动方式研究

Research on soft start mode of grading discrete frequency conversion for mine asynchronous motor

针对传统矿用异步电动机软启动方式存在电动机启动电流大、启动转矩小、无法实现重载或满载启动的缺点,在原有的分级离散变频原理基础上,对调压电路、保护电路等进行了改进,提出了一种改进的矿用异步电动机分级离散变频软启动方式。主调压电路采用门极可关断晶闸管GTO代替传统的可控硅晶闸管来调节电源频率,并用理想型开关组代替三相断路器来控制其关断,从而防止过电压或过电流对电路造成损害,达到保护电路的目的。Matlab仿真结果表明,改进的分级离散变频软启动方式不仅能降低启动电流,增大启动转矩,还能有效保护电路。

In view of problem that traditional soft start mode of mine-used asynchronous motor has big starting current,small starting torque,and cannot achieve overload or full load start,voltage regulation circuit and protection circuit were improved based on existing grading discrete frequency conversionprinciple,and an improved soft start mode of grading discrete frequency conversion for mine asynchronous mator was put forward.The main voltage regulator circuit uses gate turn-off thyristor GTO instead of traditional SCR thyristor to adjust power frequency,and uses ideal switch group instead of three-phase circuit breaker to control its turn-off,so as to prevent circuit damage caused by over-voltage or overcurrent,and achieves purpose of circuit protect.The Matlab simulation results show that improved soft start mode of grading discrete frequency conversion can not only reduce starting current and increase starting torque,but also effectively protect the circuit.