分布式发电系统并网切换暂态过程分析  

Transients Analysis on Mode-Switching of Grid-Connected Distributed Generation Systems

作　　者：王晓寰[1] 张纯江[1] 丁峰[1] 

机构地区：[1]电力电子节能与传动控制河北省重点实验室(燕山大学),河北省秦皇岛市066004

出　　处：《电网技术》2010年第7期160-163,共4页Power System Technology

基　　金：国家自然科学基金项目(50837003)~~

摘　　要：为减小分布式发电并网过程对电网的冲击,提出从时域角度对并网暂态电路的进网电流和负载电压响应进行分析。应用电路分析原理中的基本方法,建立了分布式发电并网切换电路微分方程,推导了暂态变量表达式。考虑到三相并网电流相位相差120°,探讨了并网时刻、相位与暂态分量的特征关系。依据暂态过程中系统各变量之间的函数关系,采取有效措施抑制暂态变量,以获得切换过程的平滑过渡,实现无缝切换。仿真结果验证了该方法的正确性和可行性。To mitigate the impact on power grid and load during the mode-swithcing of grid-connected distributed generation （DG） system adopting independent/parallel operation mode, the time-domain analysis on the input current of power grid from the transient circuit being switched and the load voltage response of power grid is performed. Based on Kirchhoff’s law and volt-ampere characteristics of circuit components, the differential equation for the grid-connected DG being switched is built and the expressions of transient variables are derived. Considering the characteristic that among three-phase currents from DG to power grid the phase differences are 120° one another, the characteristical relation among the moment of the switching, phase and transient components are researched. According to the functional relation among variables during the transient process, it is proposed to adopt effective measures to eliminate transient variables to attain the smooth transition of switching process and realize seamless switching. Simulation results varify the correctness and feasibility of the proposed method.

关 键 词：分布式发电 模式切换 并蚓 暂态分析 微分方程 

分 类 号：TM614[电气工程—电力系统及自动化]