晶闸管-电动机系统不对称瞬态建模及解析  

Asymmetrical Transient Modeling and Analytical Research of SCR-Motor Systems

作　　者：李和明[1] 张自力[1] 崔学深[1] 罗应立[1] 杨娅萍[1] 

机构地区：[1]华北电力大学电气与电子工程学院,北京102206

出　　处：《电工技术学报》2013年第8期241-249,共9页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金(51077048);中央高校基本科研业务费专项资金(13XS06)资助项目

摘　　要：快速软投入、软切换等晶闸管-电动机系统中,电动机三相对称、两相不对称瞬态频繁交替出现,对其中三相到两相的过渡过程,本文提出一种基于空间矢量的电动机两相不对称瞬态建模方法。首先,明确三种定子复坐标系的概念,并在原有空间矢量定义的基础上扩充其定义,给出三种空间矢量定义式;其次,分别使用所定义的三种空间矢量,建立电动机三种两相不对称瞬态数学模型;然后,利用空间矢量间的坐标变换和具体两相不对称运行所对应的约束条件,得到使用原有空间矢量定义所描述的有利于各种不对称与对称过渡过程衔接的电动机三种两相不对称瞬态模型;最后,根据所建的电动机空间矢量模型,解析研究空载电动机从三相对称状态过渡到一种两相不对称运行,具体呈现出初值和电源电压对定子瞬态电流的约束,并对该过程进行解析计算,发现解析计算与数值仿真、现场实验结果相吻合,从而证明了基于空间矢量的电动机两相不对称瞬态模型及解析研究的正确性。Three-phase symmetrical and two-phase asymmetrical transient operations of induction motor frequently appear alternately for SCR-motor systems, such as rapid soft switch and soft transfer. For the transition from symmetrical to asymmetrical condition, a method for modeling the two-phase asymmetrical operation of induction motor based on space vector is presented. Firstly, three stator complex reference frames are declared and three new definitions of space vector are proposed by extending the original definition of the space vector. Second, the three kinds of vectors are used respectively to build three asymmetrical transient models of motor. Third, based on the coordinates transformation among vectors and the special constraints existed in the asymmetrical operation, three asymmetrical models of motor described by the original definition of space vector are obtained which are helpful to link the transient process between the symmetrical operation and asymmetrical operation. Finally, a transition of no-load motor from symmetrical to an asymmetrical operation is researched analytically using the proposed models. And the analytical expression of stator current vector is given in detail using the initial values of currents and power source voltage. Additionally, analytical calculation is implemented in the transient process and the results are consistent with the results of numerical simulation and experiment. And the fact verifies the correctness of both the two-phase asymmetrical transient models and analytical research on motor based on vector.

关 键 词：不对称运行 空间矢量及其扩充定义 坐标变换 瞬态建模 解析研究 晶闸管-电动机系统 

分 类 号：TM32[电气工程—电机] TM346