直驱风电系统新型变流控制策略

A New Converter Control Strategy in Direct Drive Wind Generation System

本文讨论了直驱风电系统在正常运行和电网故障下运行时的控制问题,提出了一种新的变流器控制策略,该策略是建立在机侧变流器、网侧变流器和阻尼控制器协调控制的基础上,使用阻尼控制器的目的是为了抑制由于机械或电气负载变化引起的驱动链扭振。采用新型控制策略后,电网故障期间不能通过变流器传递到电网的功率从直流环节转移到了发电机侧,因此提高了故障时系统的响应速度。用仿真和实验方法对新型控制策略的性能进行了讨论和验证。

This paper addressed the control issues of direct drive wind turbine during both normal and grid faults operations, and also proposed and described a new control strategy based on a coordination between a generator-side converter controller, a grid-side converter controller and a damping controller which was designed to actively damp the torsional oscillations in the drive-train excited by mechanical or electrical load changes. When the new control strategy is used, the power was unable to be delivered from converter to grid during grid fault is shifted from DC link to generator, and hence improving system response speed during grid fault. The performance of the presented control strategy is discussed and verified by means of simulations and experiments.