An Asynchronous Motor Soft-Starter with Discrete Variable Frequency Technology

摘要

This paper analysis the control principle of the asynchronous motor soft-start with discrete variable frequency technology．A simulation model for the asynchronous motor soft-starter using discrete variable frequency technology is built based on MATLAB SIMULINK/POWER SYSTEM．In start process, positive sequence sub - frequency such as 13, 10, 7, 4 discrete variable frequency is used in the soft-starter to simplified power circuit and its control. While on the power frequency time slice, a single neuron PID algorithm is used to limit the current. The simulation results verify the asynchronous motor soft-starter with discrete variable frequency technology not only reduces the initial firing current but also has bigger start torque, which has a faster start speed compared with the normal soft starter with current limit starting control technology.