电网不平衡条件下PWM整流器最优化控制策略研究  

Optimized Control Strategies for PWM Rectifiers Under Unbalanced Input Voltage Transient

作　　者：魏克新[1] 汪水明[1] 

机构地区：[1]天津理工大学天津市复杂工业系统控制理论与应用重点实验室,天津300384

出　　处：《现代电力》2009年第5期1-6,共6页Modern Electric Power

基　　金：天津市自然科学基金(06YFJMJC01800);天津市科学技术发展基金(2006BA24)

摘　　要：整流器的控制策略和控制结构对于整流器的控制效果有着决定性的作用。针对电网电压不平衡的实际情况,以往的电压源型PWM整流器的控制策略,都是建立双电流矢量内环对交流测电流波形、输出直流侧电压进行最优化控制。但是这种控制策略需要对正负序电流进行分别控制,系统过于复杂而实现困难。提出了基于网侧交换功率平衡的控制策略。设计的PI+R控制结构改进了传统单一PI控制结构带来的控制局限性,既实现了系统的高功率因数运行,直流侧输出电压高稳态精度的控制要求,又能保证系统低谐波含量。仿真和试验的数据都验证了这一方法的优越性,它具有更加简单有效的控制结构,也具有更好的针对不平衡电网的适应能力。Control structures and strategies have critical influence on a rectifier＇s behavior during input disturbances.Most of the previous research in the field of pulse-width modulation voltage-source rectifier（VSR） operation under unbalanced conditions adopts dual vector controllers with dc bus voltage optimization strategies,which has been proven to be well adapted for rectifier applications.But such control strategies need to control both positive and negative sequence of currents,which makes the system be too complex and difficult to be implemented.The control strategy is established based on the balance of power exchange.The PI＋R control structure is adopted,and it improves the limitations of the traditional PI control strategies,which makes the system the control requirements of both high power factor and high-precision control of the DC output voltage in steady state.It is proven through both simulation and experimental analysis that the proposed control structure offers very good performances with simpler structures and better flexibility in terms of unbalanced input voltage operation situations.

关 键 词：电网不平衡 PWM整流器 最优化控制策略 交换功率平衡 PI+R控制结构 

分 类 号：TP29[自动化与计算机技术—检测技术与自动化装置]