孤岛模式下逆变器并联系统的谐振特性分析及其抑制策略研究  

Analysis of Resonant Characteristics and Resonance Suppression Strategy of Inverter Parallel System in Islanding Mode

作　　者：姚骏[1] 谭义[1] 杜红彪 郭利莎 曾欣[1] 

机构地区：[1]输配电装备及系统安全与新技术国家重点实验室(重庆大学),重庆400044

出　　处：《电工技术学报》2016年第23期199-210,共12页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金项目(51477016);中央高校基本科研业务费重点项目(106112015CDJZR155516)资助

摘　　要：针对孤岛模式下逆变器并联系统的谐振问题,首先建立考虑数字控制延时以及数字滤波等非线性因素的单台逆变器系统等效模型,并由此扩展得到孤岛模式下多逆变器并联系统的等效模型。进一步提出利用孤岛模式下逆变器并联系统的等效导纳进行系统的谐振特性分析,分析结果表明多逆变器之间谐波交互可能引发系统谐振,且系统的谐振特性与虚拟阻抗、负载以及反馈滤波器等因素密切相关。最后,针对系统的谐振抑制提出合理选取虚拟电感大小并在电流反馈环节引入串联反馈滤波器的新策略。实验结果验证了所建孤岛模式下逆变器并联系统数学模型的正确性以及所提出的谐振特性分析方法和谐振抑制策略的可行性。Aiming at the resonance problem of inverter parallel system in islanding mode, the single inverter system equivalent model by considering the influence of nonlinear factors such as digital control delay and digital filters etc. was established. Furthermore,an islanding multi parallel inverter system equivalent model was achieved by extending the single equivalent model. In addition,the resonant characteristics of the parallel inverter system were further analyzed by using the equivalent admittance of islanding multi inverter parallel system. The analytical results show that the multi harmonic interaction between the inverters may cause system resonance. As a conclusion,the resonant characteristics of the system were influenced by the virtual impedances, loads and feedback filters etc. Finally,a novel strategy by carefully selecting the virtual impedance and introducing a series feedback filter in current feedback loop was proposed to suppress the system resonance. Experimental results are used to verify the correctness of islanding mode multi inverter parallel system equivalent model, and the feasibility of proposed resonant characteristics analysis method, suppression strategy are also verified by the experimental results.

关 键 词：逆变器并联 谐波交互 虚拟阻抗 等效导纳 谐振抑制 

分 类 号：TM46[电气工程—电器]