摘要
针对高频三电平变流器运行于低调制比区存在窄脉冲问题,提出开关序列空间平面限制区的概念,并设计一种混合调制策略。建立了基本矢量作用时间和功率器件开关时间的差值函数,在空间矢量平面内分析了该差值函数的图像。以此为依据分析了三电平虚拟空间矢量调制产生窄脉冲的区域,提出差值函数值小于零的区域为基本电压矢量序列的限制区,在限制区内无法实现传统虚拟空间矢量所需的基本电压矢量序列。通过限制区面积大小评估调制策略与开关频率的关系,给出不同调制策略下最高开关频率的选定方法。并给出低调制比区新型扇区划分方法,设计混合调制策略。利用三电平基本矢量的冗余性,在不同的区域设计电压矢量序列,进而实现窄脉冲的抑制。仿真及实验结果均验证了其有效性。
Aiming at the problem of narrow pulse when high-frequency three-level converter operated in low modulation index,limited region of switch pattern in space plane is proposed and a hybrid modulation strategy is designed.The difference function between the working time of the voltage vector and the switching time of the power device was established and the image of the difference function was analyzed in the space vector plane.The narrow pulse regions generated by conventional virtual space vector modulation were analyzed.The region where the difference function value is less than zero is the limited region of the basic voltage vector sequence,in which the voltage vector sequence required by the conventional virtual space vector cannot be realized.The relationship between the switching frequency and the modulation strategy was evaluated by the dimension of the limited region,and the highest switching frequency under different modulation strategies were also given.The hybrid modulation strategy was designed based on the new sector division method in low modulation index region.The voltage vector sequences were designed in different regions to suppress the narrow pulse.The effectiveness of the proposed method is verified by simulation and experimental results.
作者
李文善
温旭辉
张剑
王又珑
LI Wen-shan;WEN Xu-hui;ZHANG Jian;WANG You-long(School of Electronic,Electrical and Commutation Engineering,University of Chinese Academy of Science,Beijing 100049,China;Institute of Electrical Engineering,Chinese Academy of Science,Beijing 100190,China;Qilu Zhongke Electric Advanced Electromagnetic Drive Technology Research Institute,Jinan 250100,China;Key Laboratory of Power Electronics and Electric Drive,Institute of Electrical Engineering,Chinese Academy of Sciences,Beijing 100190,China)
出处
《电机与控制学报》
EI
CSCD
北大核心
2021年第12期116-126,共11页
Electric Machines and Control
基金
国家重大研发计划项目(2016YFB0100600)
北京市自然科学基金(3192041)。
关键词
三电平
虚拟空间矢量调制
混合调制
低调制比区
窄脉冲
基本电压矢量序列
three-level converters
virtual space vector modulation
hybrid modulation strategy
low index modulation region
narrow pulse
voltage vector sequence
