ABSTRACT

This paper presents the doubly fed induction generator (DFIG)-based wind turbine (WT) system with a back-to-back converter (B2BC) and nine-switch converter (NSC) as well as their control schemes. A new slip speed estimator-based control method is also proposed to control RSC of the DFIG-WT system. The system responses are obtained using two different converter topologies, namely (i) B2BC and (ii) NSC-based series grid-side converter (SGSC)–parallel grid-side converter (PGSC) under unbalanced/balanced grid disturbances due to balanced/unbalanced non-linear loads. Their responses are also compared to study the effectiveness of both the converter topologies. Moreover, the system responses are also obtained with the proposed slip speed estimator-based control scheme under varying wind velocity and compared with that of obtained using one of the existing control schemes. The system is modeled in MATLAB/Simulink platform. The time-domain simulation results are presented and analyzed in details. Results show that the B2BC- used with DFIG-WT system can be replaced by NSC under any loading condition and also the proposed slip speed estimator can offer good performance under varying wind velocity.

摘要

本文介绍了基于双馈感应发电机 (DFIG) 的风力涡轮机 (WT) 系统，该系统具有背靠背转换器 (B2BC) 和九开关转换器 (NSC) 及其控制方案。还提出了一种新的基于滑差速度估计器的控制方法来控制 DFIG-WT 系统的 RSC。系统响应是使用两种不同的变流器拓扑获得的，即 (i) B2BC 和 (ii) 基于 NSC 的串联网侧变流器 (SGSC)-并联网侧变流器 (PGSC) 在由平衡/平衡引起的不平衡/平衡电网扰动下不平衡的非线性负载。还比较了它们的响应，以研究两种转换器拓扑的有效性。而且，系统响应也通过所提出的基于滑差速度估计器的控制方案在变化的风速下获得，并与使用现有控制方案之一获得的系统响应进行比较。该系统在MATLAB/Simulink平台上建模。给出并详细分析了时域仿真结果。结果表明，在任何负载条件下，与 DFIG-WT 系统一起使用的 B2BC- 都可以被 NSC 取代，并且所提出的滑移速度估计器可以在不同风速下提供良好的性能。