H6结构不隔离光伏并网逆变器边界碰撞分岔与稳定域

BORDER-COLLISION BIFURCATION AND STABILITY DOMAIN OF NON-ISOLATED PHOTOVOLTAIC GRID-CONNECTED INVERTER WITH H6-TYPE

为分析电流比例控制H6结构不隔离光伏并网逆变器(current proportion controlled non-isolated photovoltaicgrid-connected inverter with H6-type,CPNPGI-H6)系统的分岔现象,确定其参数的稳定工作范围,基于准静态思想建立CPNPGI-H6系统的离散迭代映射模型,并推导电感电流i的2个工作边界;通过对比例系数k_p变化的分岔行为研究表明,CPNPGI-H6系统存在一种由多周期态经边界碰撞分岔进入混沌的新路由;采用分岔图分析系统输入电压E、并网电压幅值U_m、负载电感L、负载电阻R等外参数变化时系统的工作特性,得出相应的稳定域,为系统外参数的选择提供可靠依据。

In order to analyze bifurcation phenomena and stability domain of parameter in the Current Proportion controlled Non-isolated Photovoltaic Grid-connected Inverter with H6-type(CPNPGI-H6)system,the discrete model of the CPNPGI-H6 system is established in this paper,which is based on quasi-static theory,meanwhile the two collision border lines of the inductance current i are studied. Secondly,the analysis result of the bifurcation diagram by changing values of proportional coefficient kp,which showed a new route the CPNPGI-H6 system enters chaos is from muti-period through the border-collision bifurcation. Then,stability domain of the system are studied through analyzing the bifurcation diagram when external parameters of the system input voltage E,the amplitude of grid-connected voltage Um load resistance R and load inductance L are used as changing parameters,and corresponding stability domain of the system is obtained,which has provided the reliable basis for the external parameter choice.