毕业设计-分布式发电系统下垂控制策略的研究.doc

本科毕业设计（论文）分布式发电系统下垂控制策略的研究***燕 山 大 学 2012年6月摘要I摘 要 论文分析了传统的下垂控制策略在微电网系统中应用所存在的缺陷，并提出采用倒下垂控制与下垂控制相结合的综合控制策略。该策略在改善微电网的稳定性，最大限度地限制过流情况发生等方面都具有显著特点，而且能实现微电网在网络结构或状态转换过程的无缝切换，同时也为不同响应时间的储能装置选择合适的控制策略提供了可能。 论文从逆变电源主电路拓扑、电压控制型逆变电源的输出特性与控制稳定性、电流控制型逆变电源的输出特性与控制稳定性等方面展开研究，详细全面地阐述了系统综合控制策略的控制思想及其稳定性。具体设计了逆变单元输出滤波器参数、逆变电压瞬时双闭环调节控制器、调节功率的电流闭环的控制器。建立了下垂并联控制的数学模型及综合控制微电网系统的数学模型，分析和讨论并佐以波特图阐述了各控制参数对系统稳定性的影响，为系统的优化设计提供了参考依据。最后建立基于单相逆变电源的微电网控制系统PSCAD仿真模型，并通过仿真实验对其进行验证分析，结果表明：论文提出的综合控制策略在系统的动态性能与稳态特性方面均具有很好的效果。关键词　分布式发电 微电网 逆变电源 下垂控制 倒下垂控制 AbstractIIIII Abstract The defects of conventional droop control strategy are analyzed that applied in microgrid system，and the synthetic control strategy composed of droop control aIld1nverse droop control strategy is proposed．This control strategy perfects well in1mprovmg of stability,restricting the occurrence of over-current，achieving seamless switching during state transferring．In addition，the inverse droop control strategy provides possibility of setting different response time by various energy storage device． The system control strategy’s idea and stability are demonstrated comprehensively,and the main circuit topology,the output characteristics and control stability of voltage control type inverter and voltage control type inverter are also researched as well．The parameter of output filter and the double closed。loop voltage adjuster of inverter are designed in detail，the same is the closed。loop current adjuster for power regulation．Moreover the math model of droop parallel control and synthetic control are build，based on the model．references for system design have been analyzed and discussed．At the same time．It expounded the effects 011 system performance of each control variable in power control loop with bode diagrams．With establishing and analyzing the simulation model of microgrid system based on single inverter by MATLAB，both dynamic and steady p