A New Analytical Model for Voltage Stress Analysis at Neutral Point of Stator Windings

For inverter-driven electrical machine systems, the transient overvoltage phenomenon has attracted widespread attention because of its potential to degrade the winding insulation causing premature failure. Most existing literature has proposed that the maximum voltage occurs at the machine terminals, while some recent papers reveal the maximum voltage may occur at the neutral point of stator windings under certain combinations of conditions and machine parameters. In this paper, a new analytical model is proposed to explain and predict the voltage stress at the neutral point of stator windings. The proposed model is more intuitive, requires less computation effort, while exhibits comparable accuracy to the existing model in literature. In addition, the proposed model is used to analyse the influencing factors of neutral point voltage.