基于直接转矩控制电励磁同步电机转子励磁电流控制策略

同步电机转子励磁电流控制方式直接影响电机的运行特性。针对直接转矩控制电励磁同步电机提出一种全速度范围内转子励磁电流优化控制策略,它直接利用转矩给定和定子磁链给定计算出转子励磁电流给定值。仿真和实验结果表明:额定转速以下转子励磁电流较小,降低了转子绕组的发热;额定转速以上转子励磁电流较大,提高了电机负载能力;恒转矩区和恒功率区之间转换不需要设定过渡区,过渡平滑;全速度范围内电机的外功率因数均近似等于1。

Rotor Excitation Current Control Strategy of Electrically Excited Synchronous Motor Drive Based on DTC

The performance of electrically excited synchronous motor(ESM) drive is directly influenced by the rotor excitation current control strategy of ESM.An optimum excitation control method for a DTC-controlled ESM drive in the whole speed rang is studied.The rotor excitation current reference is directly calculated by the torque and stator flux linkage references.Simulation and experimental results show that both rotor excitation current and loss of rotor winding are decreased below the rated speed;the loading ability is increased for the increased rotor excitation current over the rated speed;the change between the unit inner and outer power factor control directly happens at the rated speed without transition;the outer power factor approximatively equals to unite in the whole speed rang.