一种高起动转矩的感应电机起动方法

基于六边形空间电压矢量基本原理,提出一种高起动转矩的感应电机起动控制方法。首先分析在工频正弦电网上利用六边形空间电压矢量实现离散变频的原理,并从转子旋转磁链轨迹证明其可行性。然后利用大功率感应电机特性说明空间电压矢量变频下电流断续时间内磁链几乎不衰减,再通过电压矢量的平移实现基于六边形两相导通空间电压矢量的多级离散变频。采用适当的频率切换方式,使频率切换过程电机的冲击最小,近似达到离散变频无扰切换的目的。最后,通过仿真和实测结果对比,验证了所提出的起动方法的有效性。该方法降低了起动电流、提高了起动转矩,具有一定的理论研究和实际应用价值。

A Starting Method of Induction Motor with High Starting Torque

Based on the basic principle of the hexagonal space voltage vector,a starting control method of induction motor with high starting torque is proposed.Firstly,the principle of realizing discrete frequency conversion by using hexagonal space voltage vector on the power frequency sine grid is analyzed,and its feasibility from rotor rotating flux track is proved.Then,the unattenuated flux in the current interrupted time of space voltage vector frequency conversion is illustrated by using the characteristic of high power induction motor,the multilevel discrete variable frequency based on hexagonal phase space voltage vector is realized through the translation of the voltage vector.The impact of the frequency switching process is minimized by using a specific frequency switching mode,the purpose of discrete frequency conversion without interference is almost achieved.Lastly,through the comparison between the simulation and the measured results,the effectiveness of the proposed method is verified.The purpose of reducing starting current and improving torque is reached,having certain theoretical research and practical application value.