双馈式变速恒频风力发电机的空载及负载并网策略

Strategies of Grid-Connection of Doubly-Fed Variable-Speed Constant-Frequency Wind Power Generator with No-Load and with Load

双馈式变速恒频(DFVSCF)风力发电机在转子侧施加交流励磁,快速调节定子电压,以满足并网条件。本文利用这一柔性连接特性,采用磁场定向矢量控制技术,研究了双馈式变速恒频风力发电机的空载、负载两种并网控制原理,建立了基于定子磁链定向矢量控制下的两种并网策略,给出了两种策略下的转子电流控制模型,并设计了不依赖于发电机参数的u-ω型磁链观测器,实现了变速情况下DFVSCF风力发电机的安全并网。最后进行了实验研究,证明了两种并网策略的正确性及有效性。

In the situation of doubly-fed variable-speed constant-frequency（DFVSCF） wind power generator using AC excitation applied to rotor,the stator voltage can be regulated quickly to meet the condition of grid-connection.With this flexible connectivity,the method of field-oriented vector control was adopted in this paper,and then the control principles of grid-connection with no-load and with load of DFVSCF wind power generator was investigated.Two strategies of grid-connection,together with their corresponding rotor current control models were established based on stator flux oriented vector control technology,and one u-ω stator flux linkage observer independent of generator parameters was put forward.With the proposed control schem,the DFVSCF wind power generator can be safely connected to grid at variable speed.At last,the experimental research was conducted,and experimental result verifies the correctness and feasibility of the strategies proposed by this paper.