Simulation and study on mitigation measures of frequent subsynchronous oscillation with low amplitude at multi-power plants  

作　　者：XIAO XiangNing ZHANG Jian GAO BenFeng WU YunSheng LUO Chao GUO ChunLin YANG Lin 

机构地区：[1]State Key Laboratory for Alternate Electrical Power System with Renewable Energy Sources,North China Electric Power University [2]Shanxi Electric Power Research Institute

出　　处：《Science China(Technological Sciences)》2013年第6期1340-1353,共14页中国科学（技术科学英文版）

基　　金：supported by the Key Project of the National 12th Five-Year Research Programme of China (Grant No. 2011BAA01B02);the Fundamental Research Funds for the Central Universities of China (Grant No.12QN37)

摘　　要：Subsynchronous oscillation (SSO) with low amplitude that exceeds cumulative fatigue threshold of the generator shaft frequently could significantly reduce the shaft's service life, which is a new SSO problem that emerges in recent years. According to the real recording oscillograph, the basic reason for frequently over-threshold SSO with low amplitude at multi-power plants was analyzed based on Hulunbuir League system. The sensitivities of the electrical damping to the main electrical parameters in the contributing loop of subsynchronous torsional interaction were calculated. Based on the sensitivities, a simulation method was presented, which was used to excite the same oscillation as the actual case by exerting disturbance on the firing angle. The limitation of wide-band and narrow-band supplementary subsynchronous damping controller (SSDC) for mitigating this kind of SSO was analyzed based on the electromagnetic transient simulation model of Hulunbuir League system. The difference of supplementary excitation damping controller (SEDC) and parallel-form FACTS connected to the generator terminal was compared from the aspects of response time and the ability of damping torque supplying. The analysis indicates that their response time is similar but FACTS has stronger ability of damping torque supplying than SEDC. Time-domain simulation method was used to compare the mitigation effects of SEDC, static var compensator (SVC) and static synchronous compensator (STATCOM). Considering the mitigation effect, the floor space limit of the power plant and so on, STATCOM was considered as the best mitigation measure. A control strategy of cascaded STATCOM for engineering application was presented and the capacity for SSO mitigation as well as output characteristics was analyzed. The analysis indicates that STATCOM using the proposed control strategy has better mitigation effect and output characteristics with smaller capacity.

关 键 词：subsynchronous oscillation high voltage direct current （HVDC） cumulative fatigue sensitivity mitigation measure 

分 类 号：TM621[电气工程—电力系统及自动化]