基于模糊控制的虚拟阻抗VSG功率解耦策略  

Strategy of power decoupling for VSG based on virtual impedance of fuzzy control

作　　者：陈昊 杨旭红 张云飞 刘洋 Chen Hao;Yang Xuhong;Zhang Yunfei;Liu Yang(School of Automatic Engineering,Shanghai University of Electric Power,Shanghai 200090,China)

机构地区：[1]上海电力大学自动化工程学院,上海200090

出　　处：《电测与仪表》2020年第14期135-141,共7页Electrical Measurement & Instrumentation

基　　金：上海市电站自动化技术重点实验室开放课题(13DZ2273800);上海市科技创新行动技术高新技术领域重点项目(14511101200);上海市重点科技攻关计划(上海市科委地方院校能力建设项目)(14110500700);国家自然科学基金资助项目(61203224);上海自然科学基金项目(13ZR1417800)。

摘　　要：虚拟同步发电机(VSG)技术模拟了同步发电机的运行机制,使分布式发电能够为电网提供惯性并提高系统稳定性。当VSG接入低压微电网时,由于线路阻抗的阻感比过大的影响,VSG的有功环和无功环之间不能视为近似解耦,VSG输出的有功功率和无功功率之间存在耦合。另外如果VSG的功角太大,也将增加功率的耦合程度,增加解耦的难度。文中分析了VSG功率耦合机理,发现功率耦合会引起VSG输出功率的动态震荡,使无功功率产生稳态误差等问题,在此基础上,提出了一种利用模糊控制对VSG功角进行估算的自适应虚拟阻抗解耦策略。最后,通过MATLAB/Simulink构建VSG并网模型,以验证VSG功率耦合的抑制。The virtual synchronous generator(VSG)technology mimics the operating mechanism of synchronous generators,enabling distributed generation to provide inertia to the grid and improve system stability.When the VSG is connected to the low-voltage micro-grid,the active ring and reactive ring of VSG cannot be considered as an approximate decoupling,and there is a coupling between the active and reactive power of the output of the VSG due to the influence of the high impedance ratio of the line impedance.In addition,the power coupling will be increased if the VSG power angle is too large,and the difficulty of decoupling will be increased.In this paper,the VSG power coupling mechanism is analyzed to discover that the power coupling will cause the dynamic oscillation of the VSG output power and generate the steady-state error of the reactive power.On this basis,adaptive virtual impedance decoupling strategy is proposed to decoupling,and the fuzzy control is adopted to estimate VSG power angle.Finally,the VSG grid-connected model is built by MATLAB/Simulink to verify the suppression of the VSG power coupling.

关 键 词：VSG 功率解耦 自适应虚拟阻抗 模糊控制 功角估算 

分 类 号：TM933[电气工程—电力电子与电力传动]