适应于电网高风电渗透率下的双馈风电机组惯性控制方法

为解决风电渗透率增加带来的电网频率安全稳定问题,在揭示传统微分惯性控制方法缺点的基础上,提出了一种适应于高风电渗透率、大功率缺额条件下的双馈风电机组惯性控制方法,即模式转换法。通过设置系统频率微分、频率偏差逻辑判断条件启动惯性响应,设置转速限制判断条件闭锁惯性响应,实现风电机组在最大功率跟踪工作模式与惯性响应工作模式间自主转换。该方法设置恒定附加电磁转矩步长,惯性响应作用强度不随转速降低而减弱。当系统频率事故发生时,较微分惯性控制方法,模式转换法可使风电机组在稳定运行约束范围内更加有效地抑制系统频率跌落。仿真结果验证了模式转换法的有效性和优越性。

An Inertial Control Method of Doubly Fed Induction Generators Suitable for Power Grid with High Wind Power Penetration

To address the frequency security and stability issues caused by increasing wind power penetration, an inertial control method of doubly fed induction generators suitable for high wind power penetration and large power shortfall conditions is proposed based on revealing the shortcomings of tradition differential inertial control method, namely mode switching method. The inertial control mode is triggered by setting logic judgment conditions including frequency derivative and frequency deviation, and is blocked by setting rotor speed limit, thereby the operating mode switchover between maximum power point tracking (MPPT) and inertial response can be achieved autonomously. An additional constant electromagnetic torque is set in this method, and the inertial response intensity does not recede with decrease of rotor speed. The system frequency excursion can be inhibited more effectively using mode switching method instead of differential inertial control method within the stable operation constraint of wind turbine to mitigate frequency deviations. The effectiveness and superiority of mode switching method are validated by simulation results. This work is supported by National Natural Science Foundation of China (No. 51190104).