Analysis of fault conditions in permanentmagnet in-wheel motors

Abstract: The use of light in-wheel motors is an attractive alternative for smaller passenger vehicles in urban areas. An in-wheel motor design has already been developed in a previous master thesis project. In this project, the proposed design is further analysed during electrical faults using a FEM software package (JMAG). A failure modes and effects analysis (FMEA) is carried out to identify the important faults. The faults simulated in this project are: phase short circuit, phase open circuit, high impedance, inter-turn short circuit, magnetization faults and inverter faults. Each of these faults is then further divided into the second level detailed faults. Four new JMAG models are developed based on the JMAG model in the previous master thesis. Each fault is simulated by using a suitable JMAG model. The simulation results under fault conditions and those under normal conditions of the corresponding JMAG models are then compared and analysed. A demagnetization check and a simple thermal check during fault conditions are carried out. At last a torque-speed model is discussed for further study based on the obtained torque under fault conditions.