【作者】 谢胜利；

【导师】 颜湘武； 陈峰；

【作者基本信息】 华北电力大学（河北） ， 电气工程， 2007， 硕士

【摘要】 串级调速通过在绕线式电动机转子回路中串入可调节的附加电势来改变电动机的转差以达到调速的目的。对于风机和泵类负载,它具有高效、可靠和成本低的优点。但是,传统的串级调速系统功率因数低,谐波含量较高,这些因素限制了其进一步地推广和应用。本文首先详述了串级调速系统的工作原理,分析了传统的串级调速系统谐波的产生以及功率因数低的原因;其次,利用MATLAB/SIMULINK搭建了传统串级调速系统仿真模型,得到了系统功率因数及谐波相对触发角变化而变化的曲线;针对传统串级调速系统功率因数低、谐波含量大的缺点,利用升压式斩波器改进主回路拓扑结构,并利用MATLAB/SIMULINK搭建了改进型升压式斩波器串级调速系统仿真模型,通过仿真获得了不同占空比下系统的功率因数和谐波情况,表明低速时系统的功率因数仍然较低且含有一定谐波;最后设计了无功补偿和谐波抑制装置对升压斩波式串级调速系统的无功功率进行补偿和谐波滤除,仿真结果表明,利用传统的无功补偿和谐波抑制方法能有效提高斩波式串级调速系统的功率因数和减小谐波含量。更多还原

【Abstract】 The slip energy recovery drive system (SERDS) can change the motor speed by cascading a variable three phase AC source in the rotor side. It is a high efficient,reliable and low cost scheme for fan or pump drive system. On the other hand, it has the shortage of low power factor and high harmonic distortion which prevents it from spreading and using.In this paper, the basic principle is discussed,and the harmonic distortion and power factor of the system are analyzed. The simulation circuit of traditional SERDS is built up by using MATLAB/SIMULINK and the relationship between power factor, harmonic distortion and the fire angle is obtained. Aiming at the shortage of traditional SERDS,boost chopper type is proposed,the relationship between power factor,harmonic and duty ratio is also obtained and the result shows that the power factor of the system is low and the harmonic distortion is high when the motor speed is low. So, an reactive power compensation and harmonic filter device is design to improve,and simulating result shows that the power factor and the harmonic distortion can be improved by using traditional method.更多还原