基于多绕组永磁发电机的大容量级联型风力发电变换器

针对大容量风电机组的中压变换问题，本文研究一种基于多绕组发电机的模块化级联型变换器，通过模块单元级联实现中压输出，从而省去升压变压器。对模块中发电机的两个正交绕组经PFC整流后在直流母线上并联，实现发电机单位功率因数运行，并保持馈入直流母线的瞬时功率恒定。利用发电机的电枢电感作为升压电路的储能电感，减小了系统的体积和成本，导出了电感取值的适用范围。逆变侧的H桥单元级联电路采用矢量控制，独立调节馈入电网的有功和无功功率。仿真和试验结果验证了该类变换器的拓扑结构和控制方法的有效性。
Abstract: This paper has presented a module-cascaded system for multi-coil direct-drive permanent magnet wind generator system with high voltage output, eliminating the grid-side step-up transformer. The generator coils with 90 degree phase shift are rectified through PFC circuit and connected in parallel to get unit power factor and stable dc-link power. The generator armature inductance is used for the AC-side PFC inductor, thus reducing the system size and cost. The required value of the inductor is derived based on the current ripple and zero-crossing distortion. The H-bridge inverters are cascaded to achieve high voltage output and the vector control scheme regulates the system active and reactive power output. Simulation and experimental results validate the proposed topology and control method.
关键词：风力发电；永磁直驱；单元化模块；H桥级联
Key words: wind generation, direct-drive, modular approach, cascade H-bridge