不平衡电网中三相脉冲调宽整流器的控制 - 控制理论与应用.PDF

27 8 Vol. 27 No. 8 2010 8 Control Theory Applications Aug. 2010 : 1000−8152(2010)08−1097−06 1 2 1 3 1 3 , , , , , (1. () , 257061; 2. , 450052; 3. , 067000) : , , , . , PWM , PI, , , PWM. : , , . : ; ; ; PI; : TM46 : A Control scheme for three-phase pulse-width-modulation rectifier under unbalanced grid conditions 1 2 1 KANG Zhong-jian , CHEN Tian-li , ZI Shu-wei , 3 1 3 WANG Sheng-hua , LIU Xing , WANG Ping (1. Electric Engineering Department, China University of Petroleum, Dongying Shandong 257061, China; 2. China Nuclear Power Engineering Co. Ltd., Zhengzhou Branch, Zhengzhou Henan 450052, China; 3. Electric and Electronic Engineering Department, Chengde Petroleum College, Chengde Hebei 067000, China) Abstract: By the mathematical model of the pulse-width-modulation(PWM) rectifier and the characteristics of the unbalanced grid, we propose a new dual close-loop controller for the three-phase rectifier to reduce the second-harmonic power content on the DC side when the grid voltages are unbalanced. A fuzzy PI control is used in the voltage outer-loop to improve the speed of the dynamic response. Separate controls for the positive and negative sequence currents are employed in the current inter-loop with no decomposition of the current. The simulation results show that the proposed controller adjusts the DC voltage rapidly, reduces the harmonic power content and improves the dynamic performance of rectification un