单相SPWM逆变器快标分叉控制及其稳定性分析

Control of fast-scale bifurcation in single-phase SPWM inverter and its stability analysis

在电力电子电路中,H桥逆变器是一类基本的非线性电路拓扑,在工作过程中,由于电路属于时变参数系统,使得其中很容易产生时间域上的快标不稳定现象,斜坡补偿是一种简单而有效的方法,可以很好地削弱这种不稳定现象.在一般电路应用中,斜坡补偿主要依赖于经验设计,缺乏必要的设计准则.本文将从非线性系统的分叉控制理论出发,对峰值电流模式控制H桥逆变器中的斜坡补偿进行详细地分析和研究,给出了斜坡信号补偿幅度的理论要求.分析计算结果和大量的精确仿真结果是一致的,电路在稳定工作的同时,各项性能指标也获得了极大的改善.该分析方法同样适用于其他电力电子电路的稳定性分析.

H bridge inverter is a basic nonlinear topology in power electronic circuits. However it is prone to the generauon of tast-scale instability phenomenon due to the variation of some parameters in the operation process, which can be eliminated with the slope compensation simply and effectively. Experience plays the leading role and common engineering design is lacking in necessary design criteria. Accrording to the bifurcation control theory of nonlinear system, in this paper we analyze the implementation of slope compensation on H bridge inverter under peak current mode control in detail, thereby obtaining the accurate amplitude requirements of the compensated slope signal and realize the optimization. The results of the analysis are consistent with those of simulation experiment, and the inverter circuit under appropriate slope compensation can operate in stable regime especially, with the performances being enhanced remarkably. The research method is also applicable for the stability analysis of other power electronic circuits.