基于感应电动机负荷的物理机理特性,对感应电动机群的单机等值模型的建模方法进行深入研究。首先提出一种有效的电动机群分类方法,它能将任意一群感应电动机负荷分为稳定性好和稳定性差的2个子群。其次基于能反映电动机机电特性的几个重要运行指标,提出一种感应电动机群的单机等值算法。然后根据对所有电动机的分群结果引入主导电动机群的概念,对等值惯性时间常数及转子电阻进行修正。经过仿真对比表明,在大扰动运行方式下甚至是涉及到系统失稳的条件下,应用该算法得到的电动机群单机等值模型均能达到满意精度。
The single-unit aggregated equivalent model of the induction motors was studied based on their physical mechanism characteristics. Firstly, a new effective method was proposed to classify a random group of induction motors into two subgroups, one subgroup with good stabilities, and the other with bad stabilities. Secondly, an aggregation algorithm was introduced to represent a group of induction motors by an equivalent model on the basis of several significant operating indices which reflect the electromechanical characteristics of the induction motor. Then the proposed conception of dominant motors was used to revise the inertial time constant and rotor resistance. Lastly, the test results indicated that the single-unit equivalent model could attain satisfactory accuracy to simulate all the original individual induction motors under the operation conditions with large disturbances, or even in some cases losing stabilities.