一种数字控制单相全桥逆变电路运动行为分析方法研究

Analysis of dynamic behavior in the digitally controlled single-phase full-bridge inverter

考虑到数字控制单相全桥逆变电路PWM调制方法和滤波器、负载结构的多样性,以及利用状态转移矩阵对系统运动行为分析方法的局限性.通过解析表达状态转移矩阵中的元素,本文提出了一种可以解析描述具有N个状态变量、一个开关周期内M次拓扑变化的数字控制单相全桥逆变电路(简称N-M数字控制单相全桥逆变电路)系统参数与运动行为关系的分析方法.以3-3数字控制单相全桥电压逆变电路为例对上述分析方法进行了验证,推导出了该三阶电路发生Hopf分岔的解析判别式、稳定范围及Hopf分岔振荡频率的解析表达式,并通过Simulink仿真及电路实验证明了理论分析的正确性.

Considering the multiformity in the PWM modulation principle,the diversity in the structures of filter and load,and the limitation of the method based on state transition matrix in the analysis of digital controlled single-phase full-bridge inverter,we present a new method based on analytic expression of the elements in the state transition matrix.This method can analytically express the relationship between the parameters and the dynamic motion of a system named N-M digitally controlled single-phase full-bridge inverter,which has N state variables and structure changing M times within one switching cycle.As an example,the discriminant of Hopf bifurcation, the analytic expressions of the stability boundary and the oscillation frequency of a 3-3 digitally controlled single-phase full-bridge inverter are derived.Finally,the theoretical results are verified by simulations and circuit experiments.