Outer-rotor ringed-pole SPM starter-alternator suited for sensorless drives

The paper proposes a new outer-rotor configuration for an SPM starter alternator suited to be incorporated in a sensorless drive. To this aim, the rotor has a ringed-pole structure that has been already demonstrated to be adequate for zero and low speed sensorless position detection by a signal injection technique. The paper presents the machine description and modeling, the design of the sensorless drive control, predicted performance by simulations, measures on the motor, and preliminary drive performance test results.