双馈风电场接入串补输电系统引发次同步谐振的研究模型

双馈风电场连接固定串联电容补偿输送电力的系统容易产生次同步谐振(SSR)。对于经电力电子变流装置接入系统的双馈风电场,其SSR特性与传统的SSR不同,双馈风机的变流器控制环节对SSR具有重要的影响。为了分析这种电力电子设备接入导致的新型SSR问题,以发生了此类SSR事故的国内某大规模风电汇集地区风电场为原型,建立了实际系统的等值模型。该等值模型可以作为研究此类SSR问题的一种标准模型,从而进一步对其产生机理、振荡特性以及抑制措施展开研究。验证了所提研究模型的有效性。利用该模型,通过时域仿真方法分析出各因素对双馈风机串补系统稳定性的影响。根据得到的结论提出了抑制此类SSR的措施。

A study model for subsynchronous resonance in DFIG based wind farms connected to a series-compensated power system

Subsynchronous resonance (SSR) may occur in DFIG based wind farms connected to series compensated transmission systems. Different from the traditional SSR accident, the converter control parameters have an important influence on the SSR phenomenon because of the access of power electronic equipment. In order to facilitate research on the new SSR problems caused by the access of power electronics devices, this paper establishes an equivalent model based on the actual parameters of some wind farms, where this kind of SSR accident has taken place. The equivalent model can be used as a standard model for studying the mechanism, characteristics and mitigation of this kind of SSR problem. Then, the validity of the proposed model is verified. Further, a time-domain simulation method is used to analyze this study model, so as to obtain the influence of the changes of various factors on DFIG stability. Some measures are put forward to mitigate such SSR accidents based on the results of the analysis. This work is supported by National Key Research and Development Program of China (No. 2016YFB0900104), Science and Technology Project of State Grid Corporation of China (No. SGXJ0000KXJS1700841), and Integration Project of Smart Grid Joint Fund of National Natural Science Foundation of China (No. U1866601).