高电压技术2023，Vol.49Issue(12)：5142-5150,9.DOI:10.13336/j.1003-6520.hve.20230295
基于SHEPWM电压矢量寻优的中点电位平衡控制算法
Neutral Point Potential Balance Control Algorithm Based on Voltage Vector Optimization of SHEPWM
摘要
Abstract
With the rapid development of medium and high voltage high-power inverters,more and more attention has been paid to reducing switching loss and improving system efficiency.The most common way is lowering switching fre-quency,which can lead to a deterioration of the harmonic performance of the output voltage.Applying specific harmonic elimination pulse width modulation(SHEPWM)can achieve a good harmonic performance at low switching frequencies.However,there is an inherent problem of neutral point potential imbalance when SHEPWM is applied to neutral point clamped(NPC)three-level inverters,which asks for an active balance control.To keep the good harmonic performance of SHEPWM at low switching frequencies,the existing methods of switch angle correction and redundant small vectors have to live with a weak ability on neutral point potential control.To overcome these shortcomings,an algorithm of neu-tral point potential balancing is presented in this paper,based on optimization of SHEPWM voltage vectors.By establishing the cost function of neutral point potential and traversing the voltage vectors,the switching state and action time are both corrected online,and the process of neutral point potential balancing is sped up.Experimental results show that,under a limited number of switching redundant small vectors and a fixed value of correcting switching angles,the proposed algorithm holds a shorter balancing time compared with the two existing methods above,and balances the switching frequency and balancing time at the same time.关键词
三电平逆变器/中点钳位/中点电位平衡/特定次谐波消除/低开关频率/电压矢量/开关角Key words
three-level inverter/neutral point clamped/neutral point potential balancing/selective harmonics elimination/low switching frequency/voltage vector/switching angle引用本文复制引用
霍冬阳,孟庆云,胡安琪,周亮,李卫超..基于SHEPWM电压矢量寻优的中点电位平衡控制算法[J].高电压技术,2023,49(12):5142-5150,9.基金项目
国家自然科学基金(52277207) （52277207）
国防科技重点实验室基金(6142217210306).Project supported by National Natural Science Foundation of China(52277207),Key Laboratory Fund for National Defense Science and Technolo-gy(6142217210306). （6142217210306）
