Analysis of Three-Phase Sudden Short-Circuits of Synchronous Reluctance Motors without and with Ferrite Magnet Assistance

摘要

The three-phase sudden short-circuits of synchronous reluctance motors without and with ferrite magnet assistance are analytically and numerically calculated at no-load and load operation conditions. These calculations are compared to measurement results of two four-pole 11 kW prototype motors at motor no-load. The partial irreversible demagnetization of the ferrite magnets is analyzed with numerical simulations and linked to the measurements. The post-fault operation of the partially demagnetized ferrite-assisted synchronous reluctance motor shows that the maximum steady-state output power is decreased from 15.7 kW to 14.7 kW at 1500 rpm and from 14 kW to 11.5 kW at 3000 rpm compared to the non-demagnetized motor.