Design of High Slot Fill Aluminum Winding in a Permanent Magnet Synchronous Machine With Reduced Winding Loss

Abstract

This paper presents a design of high slot fill aluminum winding in permanent magnet machines for reducing winding losses. Generally, there is a trade-off between the winding weight and the winding losses. The winding DC loss is reduced with an increase of cross-sectional areas of conductors. In general, the aluminum winding is effective for reducing the winding weight, on the other hand, the winding loss is high because the electrical conductivity is low. In this paper, a high slot fill aluminum winding of 83.8% is proposed. It overcomes the trade-off, as a result, the winding losses are significantly reduced. In particular, reducing winding DC loss contributes the decrease of the whole winding loss including winding AC losses. Two prototype machines with the proposed aluminum winding and comparable round copper winding are fabricated and tested. In experiments, both winding DC loss and whole winding losses are measured in the proposed aluminum winding and the round copper winding machines. Consequently, it is demonstrated that the proposed aluminum winding machine can reduce the whole winding losses in wide frequency region. Furthermore, efficiency improvements can be also demonstrated in the proposed aluminum winding.