摘要
单相微电网系统需要逆变器具有并网/离网双工作模式,针对工频变压器隔离型单级式单相逆变器研究了一种并网/离网双工作模式的控制策略。离网模式下采用基于准比例谐振(PR)控制器的电压外环和电感电流比例内环的双闭环控制策略,可有效控制输出电压。并网模式下利用锁相环(PLL)技术跟踪电网电压相位,采用准PR控制器实现并网电流控制。在建立单相逆变器闭环系统数学模型基础上,对逆变器在并网、离网模式及模式间平滑切换过程中的系统性能进行了分析,实验结果表明了理论分析和控制策略的正确性。
According to the requirement that an inverter may operate in the grid-connected mode or off-grid mode for a single-phase micro-grid system, the control strategy of grid-connected and off-grid operation modes is studied for an isolated single-stage single-phase inverter with a line-frequency transformer.A voltage outer loop based on the modi- fied proportional resonant(PR) controller and an inductor current proportional inner loop are used in the off-grid mode,thus the output voltage is effectively controlled.In the grid-connected mode,grid voltage phase is tracked by a phase-locked loop (PLL) and the modified PR controller is also utilized for the grid-connected current control.The mathematic model of the whole closed-loop control system for the single-phase inverter is presented, the system per- formance in grid-connected operation mode, off-grid operation mode, and their transition process between two modes are discussed.Experimental results show that the theory analysis and control strategy are right.
出处
《电力电子技术》
CSCD
北大核心
2014年第1期1-3,共3页
Power Electronics
基金
陕西省教育厅基金项目(2012JC17,12JK0567,2013JK0999)
高等学校博士学科点专项科研基金(20116118110006)~~
关键词
逆变器
准比例谐振
并网模式
离网模式
inverter
modified proportional resonant
grid-connected mode
off-grid mode