The paper focuses on the method of vector control of a doubly fed induction machine connected to the unbalanced power network with simultaneous grid voltage harmonics distortions. As the instantaneous values of torque and the q_s component of power are independent, torque oscillations during grid voltage harmonics can be achieved for different waveforms of q_s power, so a different shape of stator current can be reached at this state. Thus, alternative control targets giving non-oscillatory electromagnetic torque are analyzed and realized in the control. The commanded variables are electromagnetic torque T_em and alternatively, the q_s component of stator instantaneous power or a new variable z_s calculated in the same way as the q_s component of power but the amplitudes of each voltage harmonics are reduced k -times, where k is the harmonic order. The paper discusses how reference stator current vector components can be calculated for each type of torque oscillations cancellation target. The analysis is complemented with a simulation of a 2 MW model and laboratory tests of a small power machine.

中文翻译：

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电网不平衡和畸变的双馈感应电机转矩振荡抵消目标

本文着重研究与电网电压谐波同时失真的不平衡电网连接的双馈感应电机的矢量控制方法。作为扭矩的瞬时值和q_小号 功率分量是独立的，对于不同的波形，可以实现电网电压谐波期间的转矩振荡 q_小号功率，因此在此状态下可以达到不同形状的定子电流。因此，在控制中分析和实现了给出非振荡电磁转矩的替代控制目标。指令变量是电磁转矩Ť _EM 或者， q_小号 定子瞬时功率的分量或新变量 ž_小号 计算方法与 q_小号 功率分量，但每个电压谐波的幅度都减小了 ķ -次，在哪里 ķ是谐波阶数 本文讨论了如何为每种类型的转矩振荡消除目标计算参考定子电流矢量分量。该分析辅以2 MW模型的仿真和小型动力机的实验室测试。