含恒功率和下垂控制机组的微网小信号模型简化分析  

Simplified Small Signal Analysis of Microgrid with the Droop and PQ Generators

作　　者：范元亮[1] 江全元[1] 曹一家[2] 

机构地区：[1]浙江大学电气工程学院,浙江杭州310007 [2]湖南大学电气与信息工程学院,湖南长沙410082

出　　处：《湖南大学学报（自然科学版）》2012年第5期53-58,共6页Journal of Hunan University:Natural Sciences

基　　金：国家科技部863计划项目(2009AA05Z221);教育部新世纪优秀人才资助项目(NCET-08-0489);浙江省杰出青年基金资助项目(R1080089)

摘　　要：为了使微网小信号模型更加简练,分别只考虑采用下垂控制策略机组和采用恒功率(PQ)控制策略机组的下垂控制环节、直流侧电压和无功控制环节的动态性能.由于交流侧滤波电抗一般大于线路阻抗,近似认为采用PQ控制策略机组的输出功率取决于其逆变器桥臂输出电压的幅值和相角,从而可跟下垂控制简化模型相统一,便于小信号模型建立.针对取较大下垂系数难于保证功率分配外环稳定问题,在有功下垂控制环节中增设了前馈环节来改善系统稳定性,最后通过时域仿真加以验证分析结论.Abstract：In order to simplify the Microgrid small signal model, only the dynamics of the power alloca- tion loop of the droop generators and the dynamics of the DC voltage and reactive power output control loop of the PQ generator were considered. Normally, the filter reactance of the PQ generator is much lar- ger than the Microgrids line impedance and the output power of the PQ generator is approximately con- trolled by the magnitude and phase of the inverter bridge voltage. By this approximation, the small signal model of the PQ generator can be in accordance with the droop generator by defining the small signals of the magnitude and phase of the output voltage as the model states. And in order to overcome the adverse impact of the big droop coefficients on the stability of the Microgrid, a feed forward path on the real power allocation loop was added to improve the stability. Lastly, time domain simulation confirmed the above a- nalysis.

关 键 词：微网 下垂控制策略 PQ控制策略 小信号模型 

分 类 号：TM711[电气工程—电力系统及自动化]