【作者】 郭景武；

【导师】 张庆超； 陈劲松；

【作者基本信息】 天津大学 ， 电气工程， 2007， 硕士

【摘要】 本文主要对交流异步电机调速系统和UPFC进行仿真研究,在分析其数学模型的基础上建立了仿真模型,得出相关结论。论文介绍了交流电气传动技术和UPFC的发展概况及发展现状,分析了电动机变频调速技术的主要控制方法、基本组成和工作原理,研究了基于SPWM调制的异步电机变频调速系统和基于坐标变换和转子磁场定向的异步电机矢量控制系统,同时分析了UPFC的基本原理和控制策略,研究了UPFC对提高电能质量的影响。论文分析了异步电机变频控制的机械特性和V/F控制特性,研究了SPWM调制变频技术;同时研究了基于坐标变换和转子磁场定向的异步电机矢量控制系统,将定子电流解耦为励磁电流和转距电流,从而实现对转距的单独控制。在此基础上搭建了上述两种控制方式的MATLAB/SIMULINK模型,然后对两种系统仿真波形进行分析比较。经过对两种系统的仿真结果进行分析,可以得到如下结论:采用SPWM变频调速,可以使负载电动机在近似正弦波的交变电压下运行,转矩脉动小,有较好的调速性能;同时由于矢量控制系统在调速过程中保持励磁电流不变,控制转矩电流就可以控制电磁转矩,使得异步电机具有直流电机的控制性能。SPWM变频调速是现在比较普遍的变频调速方式,它适用于低速大功率场合,而矢量控制系统则是高性能的交流调速系统,其调速性能优越,在未来交流传动中必将发挥重要作用。论文从动态电能质量的角度出发,分析UPFC对电能质量的影响。在研究UPFC的基本原理和控制策略基础上,利用Matlab中的SIMULINK软件包建立了UPFC的仿真模型,并对系统谐波和UPFC之间的关系进行分析。本文分别考虑UPFC向系统注入的谐波和UPFC对系统内谐波的影响,仿真结果验证了UPFC动态模型和控制系统的正确性,它能有效提高系统的稳态和暂态稳定性,抑制系统高次谐波,提高稳态电能质量。更多还原

【Abstract】 This paper simulates the asynchronism machine speed-governing system and UPFC.It builds the simulation model based on analyzing mathematics model, and draw the conclusion. This paper introduces the development of AC electric drive technology and UPFC, analyzing the main control methods, ultimate composition and operating principle of electromotor frequency-variable and speed-governing technology. It researches the asynchronous machine frequency-variable and speed-governing system based on SPWM, and asynchronous machine vector control system based on coordinate conversion and magnetic field orientation. It analyses the basic priciple and control strategy, and researching the influence of UPFC improving quality of power supply.This paper analyses mechanical and V/F contral characteristic of asynchronous machine frequency-variable control, and reasarches SPWM. It researches vector control system of asynchronous machine, which bases on coordinate conversion and magnetic field orientation. It conceives the models of above two modulating methods on MATLAB/SIMULINK, and it analyses the result of simulation, then compares the two simulations. The result of simulation indicates that if we adopt SPWM variable frequency and speed regulation, it makes the motor run under sine wave approximately, and the rebound of torque will be smallest, it also has good characteristic of speed regulating. Because the field current is const, controlling the torque current will be the same with controlling electromagnetic torque. The vector control system performers as well as DC machine on speed regulating, and it is excellent control mode. SPWM variable frequency and speed regulation is the popular control method, but the vector control system is the efficient AC control system, it will be the future fashion because of its superiority speed regulating.The paper researchs the influence of UPFC improving quality of power supply. It builds UPFC simulation model useing SIMULINK of Matlab based on UPFC basic principle and contral strategy,analysing the connection of system harmonic and UPFC.The result of simulation indicates that UPFC dynamic model and control system are right,and it can improve the stability of system steady state and transient state, restrain system higher harmonic, and improve steady state quality of power supply.更多还原