【摘要】 本文研究了谐波起动电动机起动切换瞬变电流的规律.运用四阶尤格-库塔法,对Y-△起动和谐波起动过程的切换瞬变电流进行仿真计算,给出了计算结果,与实测值相比,获得了较为一致的结果,分析计算与实测结果表明,A型谐波起动的断电切换过程中存在着瞬变电流冲击,就其冲击幅度和持续时间看,不会对电网和电源变压器造成不良的影响.更多还原

【Abstract】 This paper describes the results of a study on the transient current after switching over from the starting mode to normal operating mode of an induction motor started by a harmonic field. The motor is a special wound-rotor induction machine with six stator terminals, which can be connected to give winding with two different pole numbers. There are no slip-rings on the rotor. A conventional analytical approach for studying the starting of a squirrel-cage induction motor by a Y-A starter is used to formulate the transient current and the solutions are found to be suitable for the motors discussed. Computer simulation results using Park’s equations are presented at different slips. Experimental results obtained agree with the simulation ones. Simulation and test results show that there is a rush current during switching over. However, the magnitude and duration of the rush current are found to be harmless to power supply provided that the switching time is chosen to be near the synchronous speed.更多还原