异步电机软起动器研究

【作者】 骆宝俊；

【导师】 徐志良；

【作者基本信息】 南京理工大学 ， 电力电子与电力传动， 2007， 硕士

【摘要】 电动机直接合闸起动时，起动瞬时的冲击电流可达电机额定电流的4～8倍，这将对电网造成很大的冲击，直接影响电网中其它用电设备的正常工作；另外起动时的冲击转矩也将近是额定转矩的两倍，这会影响电动机本身及其拖动设备的使用寿命。因此控制异步电机起动过程中过大的电流，具有较重要的经济价值。本课题正是基于此目的，对三相鼠笼式异步电动机软起动器进行了研究。本文首先介绍了电机软起动技术在国内外的发展状况及前景，对电动机的起动过程进行了理论分析，然后在综合比较各种起动方式特点的基础上，提出了软起动方法，并详细介绍了其工作原理、主电路设计。其次介绍了软起动器的硬件设计，包括主电路、控制电路、电源电路以及电流检测电路的分析与设计；并介绍了控制系统的软件设计，包括主程序、同步信号中断服务程序、触发驱动信号中断服务程序、相序检测子程序、软起动算法子程序以及键盘显示程序的实现，并对部分软件模块给出了程序流程图。最后应用MATLAB中的SIMULINK和POWER SYSTEM工具箱搭建了异步电动机在两相坐标系上的仿真模型，并搭建了基于交流调压方式软起动器系统的仿真模型。应用所建的仿真模型对异步电动机直接起动与软起动的过程进行了计算机仿真，对仿真结果进行了比较和分析，仿真结果表明该软起动器系统可以有效地减小异步电动机起动时对电网的冲击。并进一步对控制系统进行了部分调试实验。更多还原

【Abstract】 When AC motors start directly with full voltages, the current mayreach the magnitude as much as four-eight times of the rated current, whichmakes power system impactive and affect other apparatus on the same powernetwork. Moreover, the starting torque is twice as much as the rated torqueapproximately, therefore its load performance will be decreased as well.We control current in the start, have more importance of economy value.Based on these purposees, this dissertation does research on squirrel-cageAC asynchronous motor.Firstly, this thesis introduces the development of AC motor softstarter and gives an expatiation of the start on the operation principle.Then, on thebase of analysis and compare, it brings one way to accomplishthe motor soft starting, as well as the operation principle, the maincircuit design.Secondly, the hardware design and analysis of the soft-starter areintroduced, including the main circuit, control circuit, power circuit anddetect current circuit and discussed the software design of controlsystem.Including main program, synchronization signal interruptedsubroutine, drive signal interrupted subroutine, phase sequence detectionsubroutine, method subroutine and Key display subroutine. It also givesprogram flow charts.At the end of this dissertation, a model of soft starter system basedon voltage regulating is established and simulated with SIMULINK and POWERSYSTEM in MATLAB. The results of the simulation show that the system canreduce the high stating current as asynchronous motors start up directly更多还原