基于动态相似度与等值缓冲区的电动机动态等值方法  

A Dynamic Equivalent Method for Induction Motors Based on Dynamic Similarity and Buffer Zone

作　　者：周海强[1] 鞠平[1] 宋忠鹏[1] 卫志农[1] 

机构地区：[1]河海大学能源与电气学院,江苏省南京市210098

出　　处：《电力系统自动化》2010年第13期24-27,54,共5页Automation of Electric Power Systems

基　　金：国家自然科学基金资助项目(50977021);国家杰出青年科学基金资助项目(50725723)~~

摘　　要：为了更精确地描述电力大系统中电动机负荷的动态特性,提出了基于动态相似度与等值缓冲区的感应电动机动态等值方法。首先,根据2台电动机机械、电气运动模式的差异,定义了电动机动态相似度的量化指标;然后,按照外部系统各节点与边界节点电气联系的紧密程度确定了等值缓冲区,利用聚类原理,将动态相似度大的电动机分为一群进行等值;接着,应用理想变压器将不同节点的电动机、静态恒阻抗—恒电流—恒功率(ZIP)负荷分别移置到等值负荷节点,根据等值前后电动机群总功率不变、启动电流及空载电流不变的原则,推算出等值动态负荷的参数;最后,对IEEE 10机39母线系统进行了等值计算。仿真结果表明,与加权法相比,所提出的算法具有更好的潮流精度,能保证发电机摇摆曲线与等值前基本一致,较好地保持被等值部分对原系统的动态影响,有效提高了等值的静态与动态精度。To describe the dynamic characteristics of induction motor loads in power systems more precisely, a dynamic equivalent method for motors based on dynamic similarity and buffer zone is proposed. First, a quantitative index of dynamic similarity is defined according to the difference of mechanical and electrical characteristics between two motors, then the buffer zone is obtained according to the electrical connections between buses in the external system and the boundary. Moreover, motors and static constant impedance, constant current, constant power （ZIP）of different load buses are moved to the equivalent load node through an ideal transformer with complex ratio. Parameters of the equivalent motor are determined based on the group characteristics in the startup and no-load conditions. Finally, this algorithm is applied to the IEEE 10-generator and 39-bus test system. The simulation results show that the dynamic influence of the aggregated motors on the study system is retained with satisfactory accuracy. The proposed method has a better solution of both transient and static variables than the classical weighted equivalent method.

关 键 词：电动机 动态等值 动态相似度 等值缓冲区 分群准则 

分 类 号：TM32[电气工程—电机]