基于LQRI控制的三电平PWM整流器的实现

Implementation of three-level PWM rectifier based on LQRI control

研究了三电平电压型PWM整流器的新颖控制算法,针对传统LQR控制存在稳态误差,提出了含有积分控制的线性二次型最优控制算法(LQRI)。建立了基于电网电压定向三电平PWM整流器两相同步旋转坐标系下的数学模型,推导了内环控制的状态方程,实现了电流环控制参数的最优设计,并给出了采用LQRI控制器三电平PWM整流器的整体控制策略。搭建了基于DSP实现的样机试验平台,试验验证了控制方案的正确性和有效性,消除了纯LQR控制存在稳态误差的问题,改善了系统的动、静态性能。

A control scheme for three-level voltage-source PWM rectifier is researched and a control strategy based on an optimal algorithm of LQRI（Linear Quadratic Regulator with an Integrator） is proposed to eliminate the steady-state error of traditional LQR control.The mathematic model of three-level voltage-source PWM rectifier in two-phase synchronous rotation coordinates based on grid voltage orientation.The state equation of inner loop control is deduced to realize the optimal parameter design of current loop control.The overall control strategy is given for the three-level PWM rectifier based on LQRI.The prototype based upon DSP is established and the experimental results show its validity with improved dynamic and static performance of system.