摘要
变频器能量回馈装置可实现将电机再生制动的能量从变频器的直流母线回馈到交流电网中,但是由于能量回馈装置与变频器的二极管整流桥并联这一特殊结构,使得能量回馈装置运行时系统内部容易产生环流,导致变流器损耗增加,降低系统效率。通过对环流产生时的等效电路进行分析,得出环流大小主要与零开关矢量有关,进而提出一种双载波空间电压矢量控制(SVPWM)方法,通过该方法来改变逆变器的开关状态,使得逆变器不输出零矢量来抑制环流。该方法不需要增加额外硬件成本,且能有效抑制环流。仿真和实验结果表明了该方法的有效性。
The energy feedback device can feed regenerative braking energy of motor from dc bus of inverter to the power grid. Due to the parallel structure between the diode rectifier of inverter and energy feedback device, circulating current is easy to happen in the system when the energy feedback device is running. As a result, the inverter power loss will increase and efficiency of energy feedback system will reduce. Based on the analysis of the equivalent circuit within the condition of circulating current, it is found that the magnitude of circulating current is mainly related to the zero-switching vector. And then a dual-carried wave SVPWM modulation strategy is proposed. With this strategy, the switching state of energy feedback device is changed to suppress the circulating current and it will not increase additional hardware cost. The simulation results show the effectiveness of the proposed method.
作者
吕广强
顾星
LYU Guangqiang;GU Xing(School of Automation,Nanjing University of Science & Technology,Nanjing 210094,China)
出处
《电力工程技术》
2019年第4期165-170,共6页
Electric Power Engineering Technology
基金
国家自然科学基金资助项目(51807092)
关键词
能量回馈
双载波SVPWM
变频器
环流
零矢量
energy feedback
dual-carried wave SVPWM
inverter
circulating current
zero vector
