附加转速优化虚拟惯性控制的双馈风机一次调频研究

双馈风机由于自身运行特性,不再具备同步发电机所具有的惯性响应能力,导致双馈风电机组大规模并网后,减弱电力系统中惯性响应能力,系统发生功率扰动后,不足以维持频率在规定范围内变动,对电力系统稳定运行产生不良影响。首先分析电力系统引入风电机组后,风机对电力系统的影响;提出双馈风电机组附加转速优化虚拟惯性控制策略,在传统虚拟惯性控制中添加转速优化模块,并与转子转速控制相结合,使风机转子释放或吸收能量更多且平缓,减少对电网的冲击,并在该控制策略中加入转子转速保护模块,防止转子转速过低或过高,从而导致风机切出电网或对风机造成损伤,使双馈风机组具有与常规同步发电机同样的特性;最后在电网发生负荷突变情况下,引入附加转速优化虚拟惯性控制和综合控制进行仿真,验证所提出控制策略在电网等效惯性进一步降低时的有效性。

Research on Primary Frequency Regulation of Doubly-fed Induction Generator Based on Additional Speed Optimization Virtual Inertia Control

Due to the operation characteristics, the doubly-fed induction generator no longer has the inertial response ability of synchronous generator, weakening the inertial response ability in the power system on the large scale grid connected doubly-fed induction generator. After the power disturbance of the system, it is not enough to maintain the frequency change in the prescribed range, which has an adverse effect on the stable operation of the power system. In this paper, the influence of wind turbine on power system is analyzed at first, on this basis,the virtual inertial control strategy of additional speed optimization of doubly-fed induction generator is proposed,and the speed optimization module is added to the traditional virtual inertial control, and combine with speed control, so that the rotor releases or absorbs more energy in a smoother way ,reducing the impact on the rotor releases or absorbs more energy in a smoother way, reducing the impact on the power grid, and in the control strategy. The rotor speed protection module is added to prevent the rotor speed from being too low or too high,which will cause the rotor to cut out the power grid or cause damage to the rotor, so that the doubly-fed induction generator unit has the same characteristics as the conventional synchronous generators. Finally, in the case of load mutation in the power grid, the additional speed optimization virtual inertia control and integrated control are introduced for simulation. The virtual inertia control integrated control are introduced to simulate and verify the effectiveness of the propoesed control strategy if the system inertia is further reduced.