A robust sensorless control scheme for permanent-magnet motors in railway traction applications

Recently, the principle of indirect self control (ISC) has been shown to be suitable also for permanent-magnet motor drives. In this paper, which is a companion paper to [1], experimental results are presented which show that ISC is a robust and suitable control principle for permanent-magnet synchronous motors (PMSMs) in railway traction applications, also when the rotor position is not known but estimated. For PMSMs operating with a position sensor, the proposed method enables an improved system reliability if applied as a backup operation mode in the event of a failure of the position sensor.