三相电压型PWM整流器的建模方法

整流器模型建立直接影响控制策略,通常系统采用基尔霍夫定律和拉格朗日方程建立数学模型,其状态变量间存在耦合。文中针对开关函数描述的数学模型为非线性且控制器设计困难的特征,采用开关周期平均法建立系统平均模型,分离扰动得到稳态模型和线性时不变的小信号模型。结果表明,小信号模型较传统模型更有利系统控制器的设计。

Three-phase Voltage PWM Rectifier's Modeling Method

Three-phase PWM rectifier is widely used because of low input current harmonics and high power factor.The construction of system model is an important part of research,and the establishment of the rectifier model has a direct impact on the control strategy.Kirchhoff's law and the Lagrange equation are usually adopted to establish the mathematical model with coupling between variables.Since the mathematical model described by switching function is nonlinear and the controller's design is difficult,the average model of switch cycle average method is adopted to establish the system to get the steady-state model and a small signal model of linear and invariant.The results show that the small signal model is better in system controller design than the traditional model.