基于线电流解耦的三相光伏逆变器控制研究  

Control of Three-phase Photovoltaic Grid-connected Inverter Based on Line Current Decoupling

作　　者：易灵芝[1] 何素芬[1] 王根平[2] 彭寒梅[1] 邹晓[1] 

机构地区：[1]湘潭大学信息工程学院,湖南湘潭411105 [2]深圳职业技术学院机电分院,广东深圳518055

出　　处：《控制工程》2010年第1期46-50,54,共6页Control Engineering of China

基　　金：国家自然科学基金资助项目(50977080);教育部课题基金资助项目(2009-ZX-052);湖南省大学生创新基金资助项目

摘　　要：三相半桥电压源型逆变器存在三相开关控制相互干扰的问题,要实现定频滞环控制,必须对三相开关控制进行解耦。如果采用基于相电流的解耦控制方法,电流误差准确度过分依赖于逆变器交流侧的电感参数。提出基于线电流的解耦控制方法,保持某相开关状态不变,实现另外两相线电流控制的解耦,有效改善光伏逆变器输出性能;并通过采用基于积分法的定频滞环电流控制算法,提高系统控制精度。Matlab仿真结果证明,基于线电流解耦的解耦控制方法,能准确实现电流跟踪;积分滞环电流控制算法在实现定频控制的同时,能有效降低输出电流低次谐波含量,减少稳态误差。The disturbance problem of switching controll in three phase half-bridge voltage source inverter（VSI） is discussed to achieve the constant frequency hysteresis current control by using the decoupling method. A line current decoupling method is provided to divide the complex plane into six sectors based oil the locality of grid line voltage space vector. In each sector, the switch state of one phase is maintained invariable, and the controlls of the other two phase line current are decoupled. With tile integration algorithms of stabilizing the switching frequency, the control accuracy is raised. The simulation results by using Matlab show that the proposed decoupling method can make the current tracking exactly, achieve a stable switching frequency, and reduce low frequency harmonious of output current, and minimize the steady current error.

关 键 词：三相光伏逆变器 空间矢量 解耦 滞环电流控制 

分 类 号：TP27[自动化与计算机技术—检测技术与自动化装置]