Abstract 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.
Yao Jun,Tan Yi,Du Hongbiao等. Analysis of Resonant Characteristics and Resonance Suppression Strategy of Inverter Parallel System in Islanding Mode[J]. Transactions of China Electrotechnical Society, 2016, 31(23): 199-210.
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2016, Vol. 31 
