双馈风力发电机三矢量模型预测电流控制

Three-vector model predictive current control of doubly-fed wind turbines

双馈感应发电机双矢量模型预测电流控制改善了传统单矢量模型预测电流控制中存在的电压矢量方向幅值固定、电流波形质量低、转矩脉动大等问题,但仅对q轴电流实现无差拍控制,仍存在着一定的电流纹波和转矩脉动。对此,在双矢量的基础上增加矢量数目,提出了三矢量模型预测电流控制策略。该策略中的期望电压矢量由相邻2个有效电压矢量和一个零矢量合成,其范围可覆盖任意方向、任意幅值,并对双馈风机机侧变换器d轴和q轴电流进行无差拍控制,有效地减少了d、q轴电流脉动。通过仿真和实验结果分析表明,相比于单、双矢量模型预测电流控制策略,三矢量模型预测电流控制下的电流纹波和转矩脉动明显减小,具有更优异的动稳态性能。

Double-vector model predictive current control of a DFIG improves the problems of fixed voltage vector direction amplitude,low current waveform quality and large torque ripples in traditional single-vector model predictive current control.However,there are still some current ripples and torque ripples only when q-axis current is deadbeat controlled.In this regard,the number of vectors is increased on the basis of double vectors,and a three-vector model predictive current control strategy is proposed.The desired voltage vector in this strategy is composed of two adjacent effective voltage vectors and a zero vector,and its range can cover any direction and any amplitude.The current of d axis and q axis of the side of the doubly-fed wind turbine is also deadbeat controlled,so the current pulsation of d axis and q axis reduces effectively.The simulation and experimental results show that,compared with single and double vector model predictive current control strategies,the current ripples and torque ripples under the current control of the three-vector model prediction reduce significantly,showing a better dynamic and steady-state performance.