电压不平衡下双馈感应发电机机侧变换器无源控制方法

电网电压不平衡时对双馈感应发电机(DFIG)系统的正常运行有很大损害,传统的控制方法不能完全解决此问题。根据电压不平衡情况下DFIG的工作原理,文中提出了基于端口受控的耗散哈密顿(PCHD)模型的互联和阻尼分配的无源控制(IDA-PBC)方法进行DFIG机侧变换器的控制器设计,详细推导出DFIG机侧变换器分别在正序和负序下基于PCHD模型的IDA-PBC控制器,并计算出了在消除电压不平衡引起的定子输出功率的2次谐波、转子电流的2次谐波以及定子电流的2次谐波等3种不同的控制目标下对应的定子电流和转子电流的给定值。仿真和实验结果表明,所提出的控制方案能有效地抑制电网电压不平衡故障时定子及转子的不平衡电流和降低定子输出功率的波动,且优于传统的比例—积分—微分控制方法。

Passivity-based Control Method for Rotor-side Converter of Doubly-fed Induction Generator Under Unbalanced Voltage Condition

The grid voltage unbalance will bring about great damage to the running of the doubly-fed induction generator(DFIG)system, which traditional control methods can not completely solve. According to the DFIG operation principle under unbalanced voltage, introduction of interconnection and damping assignment passivity-based control(IDA-PBC)based port controlled Hamiltonian with dissipation(PCHD)model for rotor-side converter controller design and the positive and negative sequence rotor-side converter IDA-PBC controller based on PCHD is deduced in detail. At the same time, by calculating the instruction stator and rotor current value in the three control targets, the second harmonics of stator current, stator output power and rotor current are respectively eliminated. The results of software simulation and experiment demonstrate the feasibility of the theory presented for suppressing the stator and rotor imbalance current and reducing the output power fluctuation under the grid voltage unbalance fault, while verifying the control performance better than conventional proportion-integration-differentiation control system as well. This work is supported by National Natural Science Foundation of China(No. 61304134)and Key Science and Technology Plan of Shanghai(No. 14110500700).