基于滞环的四象限整流器间接电流解耦控制

摘要

四象限整流器具有网侧谐波小、功率因数可控、能量能双向流动等特点,在兆瓦级大功率场合应用广泛.传统的间接电流控制无电流反馈,过度地依赖主回路参数,因而对功率因数的控制不够准确,无功消耗大.解耦控制引入电流反馈,通过锁相环将基波电流分解成有功电流和无功电流,引入有功无功电流双闭环控制,降低了控制系统对主回路参数的敏感性,提高控制精度和稳定性.在功率解耦的基础上通过有功无功电流判断功率因数,分析矢量图得到滞环控制规律,动态地微调调制波幅值与相位,实现单位功率因数控制.该方法保留了功率解耦的控制效果,简化了控制算法.仿真和实验结果均验证了该算法理论的正确性和有效性.%Four-quadrant rectifier with its lower harmonic for power grid,controllable power factor and energy feed-back,has been widely used in mega-watt class power systems.The traditional indirect current control scheme depends heavily on the parameters of main circuit without the feedback of input grid current,so it leads to inaccurate power factor and the loss of reactive power.The current decoupling control scheme is introduced which realizes the decomposition of active reactive current through the phase-locked loop.The active and reactive current closed-loop is introduced which decreases the sensitivity of main circuit parameters.The power factor is estimated by active power and reactive current,the hysteresis control rule is gotten by the vector diagram,the modulating wave's amplitude and phase are adjusted dynamically and the power factor's controllability is achieved.The advantages of current decoupling control scheme is reserved,and the control algorithm is simplified.Simulation and experiment results prove the correctness and validity of the proposed control scheme.