双馈风电机组动态虚拟惯量和阻尼模糊自适应控制策略研究

RESEARCH ON FUZZY ADAPTIVE CONTROL STRATEGY OF DYNAMIC VIRTUAL INERTIA AND DAMPING OF DOUBLYFED WIND TURBINE

针对传统双馈风电机组虚拟同步控制(VSG)中因负载突变导致电网频率、输出有功功率波动较大和暂态调节时间过长的问题,提出一种基于模糊自适应控制策略的变参数风电机组虚拟同步发电机控制策略。首先,在机组转子侧变流器中引入VSG算法使得风电对电网频率具有主动支撑能力,并建立DFIG-VSG有功功率小信号模型分析惯量和阻尼系数对系统稳定性的影响;然后,通过分析系统暂态过程中的功频变化原理并结合不受线性量化约束的模糊算法,将虚拟惯量和阻尼的范围作为模糊自适应环节的输出论域,进而实时调整惯量和阻尼系数以降低功率超调和频率偏移。最后,在Matlab/Simulink中基于DFIG-VSG机组的仿真结果验证了所提模糊自适应VSG控制策略的可行性、有效性及优势。

Aiming at the problems in the virtual synchronous control(VSG)of traditional doublyfed wind generator,the grid frequency and output active power fluctuate greatly and the transient adjustment time is too long due to sudden load changes,a variable-parameter wind generator based on fuzzy adaptive control strategy is proposed in this paper.First,the VSG algorithm is introduced into the rotor-side converter of the unit,so that the wind power can actively support the grid frequency and the DFIG-VSG active power small signal model is established to analyze the influence of inertia and damping coefficient on the system stability.Then,by analyzing the principle of power frequency change in the transient process of the system and combining the fuzzy algorithm that is not constrained by linear quantization,the range of virtual inertia and damping is taken as the output domain of fuzzy adaptive link.And then the inertia and damping coefficient are adjusted in real time to reduce power overshoot and frequency.Finally,the feasibility,effectiveness and advantages of the proposed fuzzy adaptive VSG control strategy are verified based on the simulation results of the DFIG-VSG unit in Matlab/Simulink.