并网逆变发电系统共模传导干扰累加效应的模型预估研究

Model and Prediction of CM Conducted Emission Cumulative Effects in Parallel-inverter Generation System

分布式新能源并网发电系统因使用电力电子接口而易在电网中产生电磁干扰,对并网逆变发电系统中共模传导干扰的累加效应及其随机特性进行研究有重要的工业应用价值。首先提出了一种结构灵活的两电平三相逆变器共模传导干扰预测模型,在其基础上建立并网逆变发电系统的共模传导干扰预估模型。根据逆变器中有源/无源元器件参数的随机概率分布统计特性,利用蒙特卡罗法对并网发电系统共模传导干扰发射进行随机模拟,并对系统中主要影响因素随机变化的干扰发射作用进行了分析。Matlab模型仿真及样机实测证明了研究的有效性。

Distributed electric generation system based on renewable energy is easily to produce electromagnetic interference in a grid because of its power electronic interfaces and these EMI phenomena bring negative effects on the design and application of renewable energy generation technology. This paper studies the cumulative effects and stochastic characteristics of the common mode （CM） conducted interference in power system with grid-connected inverters. Firstly, a flexible structure EMI model of a two-level three-phase inverter is proposed for the prediction of CM conducted interference. Based on this CM model, the EMI model of a generation system with grid-connected inverters is established for the prediction of CM conducted interference. After getting the random probability distribution characteristics of active and passive components in inverters, Monte Carlo method is adopted to simulate the randomness of the CM conducted emissions in system. Finally, the impacts of various factors in the generation system are analyzed respectively and the effectiveness of the research is verified through Matlab simulation and experiments.