离网型小型风力发电系统逆变器的控制

Inverter Control of an Isolated Small Scale Wind Power Generation System

离网型小型风力发电系统中负载特性对逆变器提出了特殊的要求。文中采用三相四桥臂逆变器拓扑结构,在对称分量法的基础上建立了逆变器的控制模型,并推导了在双同步旋转d-q坐标系下的表达式。构建了基于前馈解耦的多环控制系统,实现了对正序、负序和零序分量的独立控制。实验结果证明该方案对不平衡负载有较强的抑制作用,能够为负载提供优质电能。

In the isolated small scale wind power generation systems, the load characteristics have special requirements on the inverter. In this paper, the three-phase four-leg topological structure is used. The control model of the inverter based on the symmetrical components is presented, and the expression is deduced in the bisynchronous d-q coordinates. A multi-loop control system based on the feed-forward decoupling control strategy is established, and the independent control among the positive-sequence, negative-sequence and zero-sequence components is realized. Experimental results demonstrate that this control strategy can mitigate disturbances quickly under unbalanced loads and obtain high quality output waveform.