摘要
采用基于恒压频比的分级变频方法,通过有规律地开通或者关断工频电源,获得可调的电压频率和幅值.分频后的三相电压组合很多,为了获得平滑上升且足够大的起动转矩,采用傅里叶变换提取上述电压组合中的基波电压的幅值和初始相位,按照恒压频比策略进行控制,然后逐步提高频率并起动电机,进行仿真并搭建基于单片机的实验电路.主电路由3对反并联的晶闸管与电动机串联组成,实验结果表明该策略使电机起动时能获得较小的电流和较大的起动转矩且平滑上升,与理论分析及仿真结果一致,证实该策略的有效性和可靠性.
Based on the discrete variable frequency method with constant U/f, the supply was conduc- ted or cut off regarly to get discrete variable voltage frequency and amplify. For any frequency degrade discrete voltage, its combinations are numerous. In order to get the smoothly added and big torque, the fundamental wave voltage amplitude and initial phase were derived by using Fourier trans- formation. At the same time the frequency was gradually raised according constant U/f control tactics to start up the motor. The corresponding simulations were carried out and the experiment circuits based on single chip microcomputer were set up. The main circuit was series connected by three pairs of anti-parallel thyristors. Experiment result demonstrates that there ars a small current and a big torque while starting, corresponding to the theoretical analysis and simulation result, so the above shortcoming is solved to prove the validity and reliability of the method.
出处
《华中科技大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2011年第9期62-65,共4页
Journal of Huazhong University of Science and Technology(Natural Science Edition)
基金
湖北省科技攻关项目(2006AA101B27)
关键词
变频
软起动
基波
起动转矩
单片机
variable frequency soft starting
fundamental wave
starting torque
single chip microcomputer
