三相逆变器的双模式及其平滑切换控制方法  

The Dual-Mode Control and Seamless Transfer Control Method of Three-Phase Inverter

作　　者：王明玥[1] 罗安[1] 陈燕东[1] 黄媛[1] 吕志鹏[2] 

机构地区：[1]湖南大学国家电能变换与控制工程技术研究中心,长沙410082 [2]中国电力科学研究院,北京100192

出　　处：《电工技术学报》2016年第16期124-134,共11页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金重点项目(51237003);中国与欧洲政府间国际合作计划项目(2010DFA61640)资助

摘　　要：针对微电网逆变器在并网切换时电流冲击大、在离网切换时直流侧电压波动等问题,提出了一种三相逆变器的双模式及其平滑切换控制方法。该方法包括稳态控制和切换控制两部分,其中,切换控制由软启动虚拟阻抗和单环电流反馈控制构成。同时,为防止逆变器在并网切换和稳态控制中,因相位误差造成的能量倒灌现象,提出了相位超前控制方法,并引入到下垂控制器中,给出了其频率调节实现方式。切换控制抑制了逆变器输出电流、入网电流的瞬间冲击,实现并网平滑切换。逆变器离网切换时,仅引入单环电流反馈控制加快入网电流泄放,避免由电流瞬时不平衡引起的逆变器直流侧电压波动。仿真和实验结果验证了三相逆变器的双模式及其平滑切换方法的可行性和有效性。Regarding the inrush current when a inverter connects to the micro-grid and the DC voltage fluctuation when a inverter is cut off from the grid, this paper proposes a dual-mode control and seamless transfer control method of three-phase inverter. The control scheme combines steady-state control with transfer control. Wherein, the transfer control consists of soft-start virtual impedance and single loop current control. To avoid reverse energy flow, phase lead regulation of droop control and its frequency regulation scheme are presented in the processes of grid-connecting and grid steady controls. The control method can inhibit both the impacts of the converter output current and the grid-injection current when a inverter connects to the grid, and can effectively reduce the grid-injection current to avoid the imbalance of instantaneous current when a inverter is cut off from the grid. Simulation and experimental results verify the proposed method.

关 键 词：微电网 三相逆变器 双模式控制 平滑切换 

分 类 号：TM76[电气工程—电力系统及自动化]