A New Self-Tuning Power-Factor-Based Vector Control Method for Efficient Wide-Speed Range Sensorless Drive of Permanent-Magnet Synchronous Motors

Abstract

As a simple sensorless vector control method for permanent-magnet synchronous motors (PMSMs), a power-factor-based vector control (PFVC) method has been reported. This method has the attractive characteristics that three functions such as current limit, efficiency and sensorless drive can be performed simultaneously in a simple manner. However, it was developed under the assumption that there is no practical voltage limit, and that it cannot be applied over the rated speed. This paper proposes a new PFVC method that allows PMSMs to be driven even over the rated speed under application of a practical voltage limit, while keeping the desired characteristics. The effectiveness and usefulness of the proposed method are verified through extensive experiments.