摘要 |
An electric motor (100) having a motor control system (400) including: -a current measuring means (402) for directly or indirectly measuring the electric current in the rotor windings (7) providing a rotor current value/s, -an ambient temperature measuring/estimation means (404) for measuring or estimating the ambient air temperature providing an air temperature value/s, -a rotor temperature estimation means (406, 407, 408, 409, 410, 411) for estimating a rotor temperature at least based on the rotor current value/s and the air temperature value/s, and -a current limiting means (405) for preventing overheating/burning of the rotor assembly (3) by limiting the electric current to the rotor windings (7) when the estimated rotor temperature exceeds a predetermined overheating threshold (412). |