小电容变频器两相旁路分时切换控制策略  

Time-sharing control strategy of two-phase bypass for small capac-itance inverter

作　　者：谢仕宏[1] 梁力[1] 周强[1] XIE Shi-hong;LIANG Li;ZHOU Qiang(School of Electrical and Control Engineering,Shaanxi University of Science&Technology,Xi'an 710021,China)

机构地区：[1]陕西科技大学电气与控制工程学院,陕西西安710021

出　　处：《陕西科技大学学报》2021年第5期146-152,166,共8页Journal of Shaanxi University of Science & Technology

基　　金：国家自然科学基金项目(51577110);陕西省科技厅重点研发计划项目(2018TSCXL-G-4-5)。

摘　　要：针对传统变频器驱动感应电机不能直接旁路的难题,提出了一种基于六边形空间电压矢量的两相旁路分时切换控制方法的变频软起动控制策略.首先分析感应电机系统软起动控制及旁路切换原理,其次,研究旁路分时切换过程中感应电机的供电特性,最后给出180°方波逆变旁路分时切换的实现方法.研究表明,通过控制变频器触发脉冲形成的变频器两相持续导通状态最大可达六分之一工频周期,即3.3 ms,两相旁路分时切换控制方法可防止切换过程变频器发生短路故障,切换过程感应电机冲击电流较小.Aiming at the problem that the traditional induction motor driven by variable frequency converter cannot be directly bypassed,this paper proposes a variable NB frequency soft starting control strategy based on the hexagonal space voltage vector two-phase bypass time-sharing control method.Firstly,the soft starting control and bypass switching principle of induction motor system are analyzed.Secondly,the current characteristics and power supply characteristics of induction motor in the process of bypass switching are analyzed.Finally,the realization method of the provided control strategy is given.The research shows that the maximum two-phase continuous conduction state of the inverter can reach one sixth of the power frequency cycle by controlling the trigger pulse of the converter,that is 3.3 ms.The two-phase by-pass time-sharing switching control method can prevent the short-circuit fault of the converter during the switching process,and the impulse current of the induction motor is small during the switching process.

关 键 词：六边形空间电压矢量 软起动 旁路分时切换 感应电机 

分 类 号：TM921[电气工程—电力电子与电力传动]