Loss minimization in surface permanent-magnet synchronous motor drives

The loss minimization in surface permanent-magnet synchronous motor drives is investigated. Based on theoretical analysis, a loss model controller is introduced to specify the optimal air-gap flux that minimizes losses. Theoretical results are verified experimentally. The proposed loss model controller is simple and does not adversely affect the cost and complexity of the drive. Implementation of the loss model controller does not require knowledge of the loss model. The suggested loss minimization method can be applied both in V/f- or current-controlled schemes.