Sensorless operation capability of surface-mounted permanent magnet machine based on high-frequency signal injection methods

In this paper, the investigation is focused on sensorless control capability of a surface-mounted permanent magnet (SPM) machine. To implement the high-frequency carrier signal injection-based sensorless techniques, the machine saliency is an essential requirement. Hence, the machine saliency information of the prototype SPM machine has experimentally been analyzed and measured without the need of any information of parameters under various load conditions due to the magnetic saturation by the fundamental excitation. The effectiveness of the sensorless capability is verified by the experiments based on the high-frequency rotating and pulsating signal injection-based sensorless control strategies at zero and low speeds.