摘要
VIENNA三电平整流器广泛用于风力发电、不间断电源等场合。为提高网侧电能质量,在d-q旋转坐标系下建立其数学模型及多环控制结构,根据单位功率因数工作情况下电网各相电流与同相整流器电压所需满足的重要限制条件,深入分析了d-q旋转坐标系下由多环控制及常规基于载波PWM调制方法所引起的电网电流过零点处波形畸变的原因,为减小电网电流总谐波畸变率,采用在三相参考调制电压中增加补偿分量的方法消除不满足VIENNA整流器重要限制条件的区域,使电网电流在各过零点处的畸变得到抑制,电能质量得到大大改善。利用Saber仿真系统建立了整流器模型,分析对比了增加补偿分量前后基于载波PWM调制方法下电网电流波形畸变率变化情况,验证了理论分析的正确性。
VIENNA three level rectifier is widely used in wind turbine systems,UPS systems,etc. To improve its power quality,the mathmatical model and multi-loop control structure are built under d-q synchronous coordinate system,based on the important requir-ment for grid side currents and rectifier side voltage in unit power factor operation condition,the reason for currents distortion at zero-crossing point by using multi-loop control and conventional carrier-based PWM method under d-q rotating coordinate system is deeply studied To reduce the total harmonic distortion rate of grid side currents,the way to add compensation component to three-phase refer-ence modulation voltage to eliminate the area that disobey the important limiting condition is applied,the currents distortion around ze-ro-crossing point is inhibitted and the power quality is improved. The rectifier model is built in Saber simulation system,the correct-ness of theory analysis is proved by comparing the value of currents total harmonic distortion before and after compensation component is added in carrier-based PWM method.
出处
《南方电网技术》
北大核心
2016年第2期18-23,共6页
Southern Power System Technology
基金
输配电装备及系统安全与新技术国家重点实验室自主研究项目(2007DA10512713302)~~
