Sinusoidal reluctance machine with DC winding: An attractive non-permanent magnet option

Important global efforts are underway toward lowering the cost of electric machines for electric and hybrid vehicles by reducing or eliminating the use of rare earth materials which have been experiencing significant price increases and volatility. Non-permanent magnet electric machines are a potential solution and are increasingly investigated by researchers worldwide. This paper presents a DC biased reluctance machine which is structurally similar to a conventional switched reluctance machine. This type of machine has a DC field winding and an AC three phase armature winding. It uses a conventional three phase inverter for the armature and an additional auxiliary DC/DC converter for the field winding. This reluctance machine is designed to achieve hybrid vehicle traction requirements of 55kW peak at 2800 rpm and 30kW continuous over a speed range going from 2800 rpm to 14000 rpm.