感应电机空间矢量直接转矩控制系统的效率优化

Efficiency optimization for space-vector direct torque control system of induction motor

提出了一种感应电机空间矢量直接转矩控制系统的效率最优控制方法。在定子磁链定向坐标系中,建立了计及铁芯损耗的感应电机数学模型。分析了电机损耗与转矩、转速和定子磁链的关系,推导出了不同运行工况条件下效率最优的定子磁链幅值表达式,实现了感应电机直接转矩变频调速系统的效率最优控制。实验结果表明,所提优化控制策略,在保持直接转矩控制快速动态响应特性的同时,可有效提高电机轻载时的运行效率。

An efficiency optimization strategy is proposed for the space-vector direct torque control system of induction motor. With the consideration of core loss,the mathematical model of induction motor is established in the stator-field-oriented frame and the functional relationship between the power loss and the torque,speed and stator flux is analyzed to derive the computational formula of stator flux amplitude with optimal efficiency under different operation conditions,which realizes the efficiency optimization of the frequency- variable direct-torque-controlled speed regulation system for induction motor. Experimental results show that, the proposed strategy improves the operational efficiency of induction motor with light load while keeps the fast dynamic response performance of direct torque control.