交流接触器耐受不规则暂降的微变等效分析方法

Microvariant equivalent analysis method for AC contactor tolerance to irregular dips

交流接触器电压暂降耐受性评估的现有方法是基于矩形暂降,对于不规则暂降易产生过度评估问题。提出一种适应不规则电压暂降波形的交流接触器耐受性评估方法。基于交流接触器的动作机理推导了电磁能、弹性势能和铁心动能三者的微变关系,建立了交流接触器的微变等效模型;将不规则电压暂降波形用阶跃信号序列的时域叠加形式表征,代入接触器微变等效模型,迭代计算各阶跃响应在微变时间域的叠加效应,从而建立了交流接触器在不规则暂降下的动作行为,得出交流接触器对不规则电压暂降的耐受性评判方法。对交流接触器在不规则暂降下的耐受性进行了仿真和试验,能够判断交流接触器的工作状态,有效避免了不规则暂降的过度评估。

The current method of voltage sag tolerance evaluation for AC contactor is based on rectangular sag,which is easy to overestimate the problem of irregular sag.A tolerance evaluation method of AC contactor adapted to irregular voltage dip waveform is proposed.Based on the action mechanism of AC contactor,the micro-variation relationship of electromagnetic energy,elastic potential energy and contact kinetic energy is deduced,and the micro-variation equivalent model of AC contactor is established.The irregular voltage sag waveform is represented by time-domain signal sequence,and the superposition effect of each step response in the time-domain is iteratively calculated by substituting the contactor micro-variation equivalent model,thus the action behavior of AC contactor under irregular sag is established,and the tolerance evaluation method of AC contactor to irregular voltage sag is obtained.The tolerance of AC contactor under irregular sag is simulated and tested,which can judge the working state of AC contactor and avoid overevaluation of irregular sag effectively.