（1 Zhejiang Provincial New Energy Investment Group Co., Ltd, Hangzhou 310002, China;
2 National Power Investment Group Zhejiang New Energy Co., Ltd, Hangzhou 310002, China;
3 Department of Electrical Engineering, Tsinghua University, Beijing 100084, China）
Abstract: As the operation of wind power or time-varying working condition has some effects on subsynchronous oscillation stability, the paper puts forward a SSO quantitative assessment method based on the variable condition impedance model. It expresses impedance matrix elements into the quotient of quadratic form of working conditions (i.e. fundamental voltage and current) to calculate the frequency characteristics of aggregated impedance under different operating points, analyzing SSO stability under various operating conditions. The proposed method, taking Xinjiang Hami wind power system as an example, makes quantitative analysis of oscillation stability of two typical operating conditions, and verifies them through electromagnetic transient simulation. According to the results, the change of operating conditions such as the wind turbine number and unit power output will affect the system oscillation stability. This method can effectively evaluate the system oscillation risk under different operating conditions.
Key words: subsynchronous oscillation; wind power integrated system; impedance model
参考文献
[1] 王一凡，赵成勇，郭春义. 直驱风电场与柔直互联系统的传递函数模型及其低频振荡稳定性分析[J].中国电机工程学报，2020，40(5)：1485-1498.
[2] 郭贤珊，李云丰，谢欣涛，等. 直驱风电场经柔直并网诱发的次同步振荡特性[J] . 中国电机工程学报，2020，40(4)：1149-1160.
[3] 吕敬，董鹏，施刚，等. 大型双馈风电场经 MMC-HVDC 并网的次同步振荡及其抑制[J] . 中国电机工程学报， 2015，35(19)：4852-4860.
[4] SUN Jian.Impedance-Based Stability Criterion for Grid-Connected Inverters[J].IEEE Transactions on Power Electronics，2011，26(11)：3075-3078.
[5] ZHANG Chen, CAI Xu, MOLINAS M, et al.On the Impedance Modeling and Equivalence of AC/DCSide Stability Analysis of a Grid-Tied Type-IV Wind Turbine System[J].IEEE Transactions on Energy Conversion，2019，34(2)：1000-1009.
[6] MIAO Zhixin . Impedance-model-based SSR analysis for type 3 wind generator and seriescompensated network[J].IEEE Transactions on Energy Conversion，2012，27(4)：984-991.
[7] XU Yunyang, NIAN Heng, WANG Tao, et al.Frequency coupling characteristic modeling and stability analysis of doubly fedinduction generator[J].IEEE Transactions on Energy Conversion，2018，33(3)：1475-1486.
[8] 李绍阶，王玮，唐芬，等. 基于阻抗模型的并网变流器低频振荡机理研究[J] . 电网技术，2018，42(9)： 2787-2798.
[9] VIETO I, SUN Jian.Small-signal impedance modelling of type-Ⅲ wind turbine[C]//IEEE Power & Energy Society General Meeting， 2015.
[10] 武相强，王赟程，陈新，等. 考虑频率耦合效应的三相并网逆变器序阻抗模型及其交互稳定性研究[J].中国电机工程学报，2020，40(5)：1605-1617.
[11] BAKHSHIZADEH M, WANG Xiongfei, BLAABJERG F,et al. Couplings in phase domain impedance modeling of grid-connected converters[J].IEEE Transactions on Power Electronics，2016，31(19)：6792-6796.
[12] 刘威，谢小荣，王衡，等. 基于频率耦合阻抗模型的并网变流器全工况小信号稳定性分析[J] . 中国电机工程学报，2020，40(22)：7212-7221.
[13] 张伯明，陈寿孙，严正. 高等电力网络分析[M] .北京：清华大学出版社，2007.
[14] 占颖，谢小荣，王艳辉，等. 计及模式可观度的阻抗网络聚合方法[J] . 电网技术，2021，45(6)：2328-2334.
[15] 刘华坤，谢小荣，何国庆，等. 新能源发电并网系统的同步参考坐标系阻抗模型及其稳定性判别方法[J]. 中国电机工程学报， 2017， 37(14)：4002-4008.
[16] 谢小荣，刘华坤，贺静波，等. 直驱风机风电场与交流电网相互作用引发次同步振荡的机理与特性分析[J] . 中国电机工程学报，2016，36(9)：2366-2372.
