DFIG风电场并网引发多机电力系统次同步振荡开环模式分析方法  

An Open-loop Modal Analysis Method to Examine the SSOs Caused by Grid-connected DFIGs in a Multi-machine Power System

作　　者：陈晨[1] 杜文娟[1] 王海风[1] CHEN Chen;DU Wenjuan;WANG Haifeng(State Key Laboratory of Alternate Electrical Power System with Renewable Energy sources（North China Electric Power University）,Changping District,Beijing 102206,China)

机构地区：[1]新能源电力系统国家重点实验室(华北电力大学)

出　　处：《中国电机工程学报》2018年第14期4064-4073,共10页Proceedings of the CSEE

基　　金：国家重点研发计划(2016YFB0900602);国家电网公司科技项目(52094017000W)~~

摘　　要：针对双馈感应发电机（doubly-fed induction generator,DFIG）风电场并网引发电力系统次同步振荡问题,基于开环模式谐振理论,提出一种研究多机电力系统中风电场并网引发次同步振荡的开环模式分析方法。当DFIG风电场的开环次同步振荡模式与其余电力系统的开环次同步振荡模式相近时,由于发生开环模式谐振,相应的两个闭环次同步模式中的一个的模式阻尼会降低。该开环模式分析方法可以辨识相近的开环次同步振荡模式,并根据推导出的开环模式指标估计开环模式谐振对系统稳定性的影响。同时,该方法可以有效识别参与开环模式谐振的模式与同步机、并网风电场之间的相关性,进而通过采取措施,消除DFIG风电场并网引发系统发生次同步振荡的风险。该文通过改进IEEE第一标准测试系统和多机算例系统,验证了开环模式分析方法的正确性和有效性。Based on the modal resonance theory, an open-loop modal analysis method was proposed to investigate sub-synchronous oscillations（SSOs） caused by grid-connected doubly-fed induction generators（DFIGs） in a multi-machine power system. It is found that when an open-loop SSO mode of DFIG is approaching to an open-loop SSO mode of rest of the power system, the damping of one corresponding closed-loop SSO mode will be degraded due to the occurrence of open-loop modal resonance. The closeness of those open-loop SSO modes can indicate the risk of closed-loop SSO. Moreover, an open-loop modal index（OMI） is defined to evaluate the impact of open-loop modal resonance on power system stability. Furthermore, based on the SSO modes involved in modal resonance, the most dominant SGs and DFIGs can be identified by the proposed method. Therefore, countermeasures can be adopted to that dominant SG or DFIG to eliminate the SSO risk induced by grid-connected DFIGs. The correctness and effectiveness of the proposed method are validated through a modified IEEE first benchmark power system and an example of multi-machine power system.

关 键 词：双馈风机 多风电场 次同步振荡模式 同步发电机扭振动态 模式分析 

分 类 号：TM71[电气工程—电力系统及自动化] TM74