基于双PWM高效节能变频的电动扶梯控制系统的开发

摘要

针对目前在电动扶梯上应用的通用变频器主要缺点:电动机发电运行时回馈的能量不能回馈到电网,而是消耗在制动电阻上,造成能量的浪费现象.文章提出一种新型双PWM变频调速系统:采用PWM整流器取代了其不可控二极管整流侧,逆变侧采用矢量变频控制.双PWM系统不仅能使直流电压在一定范围内可调,实现单位功率因数运行,而且可以实现电机四象限运行和电能双相传输.%Because of the many disadvantages of AC-DC-AC variable frequency speed control system, this paper have studied a new du-al-PWM variable frequency speed control system which uses PWM rectifier to take place of the uncontrolled diode in rectifier side and adopts vector frequency control method in inverter side. Not ordy the DC voltage can be adjusted in a certain range by the dual-PWM system, but also the system can operate at unit power factor, the motor can run at four quadrants, and the power can transmit reversibly.