摘要
首先分析了负载不平衡情况下单相电压型三电平脉冲整流器的工作原理,引出该电路直流侧中点电位偏移的特点。为了实现在负载不平衡的恶劣情况下直流侧中点电位平衡的控制目标,以传统的单相三电平单极性载波脉宽调制(CBPWM)方法为基础,提出了一种在负载不平衡情况下,基于电压补偿分量注入的载波脉宽调制(CBPWM-VOI)算法。理论分析表明:电压补偿分量的取值与负载有着密切关系,在一定的负载不平衡度范围内,该调制算法可以有效地控制直流侧中性点电位无偏移。计算机仿真和小功率样机实验都验证了该算法的有效性及理论计算的正确性。
The operating principle of single-phase three-level vohage-source pulse rectifier with unbalanced loads is analyzed and the voltage drift of DC-link neutral point is derived. A unipolar CBPWM-VOI （Carrier- Based Pulse Width Modulation with Voltage Offset Injection） algorithm based on traditional single-phase three-level unipolar CBPWM is proposed to control the DC-link neutral point voltage under load imbalance condition. Theoretical analysis shows that,the voltage compensating component is closely relative to the loads and the proposed modulation algorithm keeps the zero voltage drift of DC-link neutral point effectively within a certain range of load imbalance degree. The effectiveness of the proposed algorithm and the correctness of theoretical calculation are verified by the computer simulation and the experiment of a small- power prototype.
出处
《电力自动化设备》
EI
CSCD
北大核心
2013年第10期79-85,共7页
Electric Power Automation Equipment
基金
国家自然科学基金资助项目(51207131
51277153)
高铁联合基金重点资助项目(U11344205)~~
关键词
整流器
三电平
负载不平衡
中点电位控制
电压补偿分量
electric rectifiers
three level
load imbalance
neutral point voltage control
voltage offset
