Research on the load model and characteristics of inverter-fed motors for transient stability analysis

Nowadays, the applications of inverter-fed motor (IFM) are largely increasing. Due to load characteristics of the IFM different from that of the asynchronous motor (AM), if the traditional load model based on AM is routinely used, it will challenge the credibility of the analysis of system transient stability. Therefore, this paper adopted both experimental and digital methods to study steady-state and dynamic power characteristics of IFM, and construct the dynamic model of IFM. First, the widely-used IFM based on rotor-vector control is established on MATLAB platform. An actual IFM is tested in a self-designed physical system accordingly. Finally, the steady-state model and the multi-stage mathematical model in dynamic process are built for IFM. The simulation results show that the IFM will not produce power rush after system shocks, which is more beneficial to system voltage recovery. The proposed dynamic load model of IFM could help the transient stability analysis task.