Research ArticleSensorless control of ship propulsion interior permanent magnet synchronous motor based on a new sliding mode observer

- A new sliding mode observer is designed to estimate the rotor speed of the IPMSM.
- The SMO is proposed based on the current model of the IPMSM in synchronous rotating frame.
- The calculation of the rotor speed is deduced from Lyapunov function stability analysis.
- The system chattering problem in the SMO has been reduced.

This paper proposes a sensorless speed control strategy for ship propulsion interior permanent magnet synchronous motor (IPMSM) based on a new sliding-mode observer (SMO). In the SMO the low-pass filter and the method of arc-tangent calculation of extended electromotive force (EMF) or phase-locked loop (PLL) technique are not used. The calculation of the rotor speed is deduced from the Lyapunov function stability analysis. In order to reduce system chattering, sigmoid functions with switching gains being adaptively updated by fuzzy logic systems are innovatively incorporated into the SMO. Finally, simulation results for a 4.088 MW ship propulsion IPMSM and experimental results from a 7.5 kW IPMSM drive are provided to verify the effectiveness of the proposed SMO method.