中文摘要：

围绕双馈感应发电机（DFIG）空载并网问题,将基于矢量控制的电网电压定向技术应用于双馈风力发电的并网发电上,提出一种基于电网电压定向的高阶滑模控制的空载并网控制策略。从分析DFIG的运行特性入手,研究了空载并网控制原理,基于DFIG的空载数学模型,提出了具有鲁棒性的高阶滑模空载并网控制器。对DFIG并网前后的整个过程进行了仿真研究,仿真结果表明,所提出的策略是一种较理想的空载并网方式。

英文摘要：

According to the characteristic of AC-excited variable speed constant frequency wind turbine,a grid voltage orientation vector control strategy is used for doubly-fed induction generator（DFIG）.Firstly,this paper studies the running characters of DFIG,and the principle of DFIG under no-load cutting-in condition.Then according to the mathematical model of DFIG under no-load cutting-in condition,this paper proposes a higher-order sliding mode control for the model.Finally,a comprehensive system simulation on the no-load operation is carried out and the following situations are studied： before cutting-in,the transient process at the cutting-in moment and the DFIG tracks the maximum wind energy after cutting-in.The simulation results validate the proposed method.