附加阻尼控制下风电机组机网耦合载荷建模及分析

MODELING AND ANALYSIS ON MACHINE-GRID COUPLING LOADS OF WTGS WITH ADDITIONAL DAMPING CONTROL

针对附加阻尼控制下风电机组机械载荷问题,开展风电机组机网耦合载荷建模及载荷特性分析研究。采用FAST与Matlab/Simulink软件联合方法,建立综合考虑机组机械特性和电气特性的并网风电机组机网耦合载荷模型。采用所建模型开展附加阻尼控制对机组机械载荷影响的仿真分析,并复现附加阻尼控制下风电机组机械系统与电力系统的机网共振现象。结果表明,所建模型能够表征附加阻尼控制下风电机组机械系统与电力系统的耦合互作用,系统低频振荡会导致机组关键结构出现明显振动载荷,且系统振荡频率与机组机械结构固有振动频率接近时两者共振会急剧加大机组振动载荷。

In terms of mechanical loads of the wind turbine generator system(WTGS)with the additional damping control(ADC),modeling and analysis on mechanical loads are carried out for the WTGS considering machine-grid coupling.FAST associated with Matlab/Simulink is used to establish the mechanical-grid coupled model for the loads of the grid-connected WTGS,which takes into account both mechanical and electrical characteristics.Impacts of ADC on mechanical loads of the WTGS with ADC are simulated and investigated through the established model.And the resonance phenomenon between the WTGS mechanical system and the power system is recurred through the model.Results show that,the established model can effectively reflect the coupling interaction between the power system and the mechanical system in the WTGS under ADC,and the low-frequency oscillations of the power system lead to remarkable vibration loads in key WTGS structures,and when the natural vibration frequency of mechanical structures and the power system oscillation frequency approach to each other there is a sharp increase in vibration loads of a WTGS due to their resonance.