Calculation for stator loss of high-speed permanent magnet synchronous machine in torque-speed envelope and restraint approach for circulating current in windings

Abstract

Iron loss and copper loss are the significant parts of electrical loss of machines, which are the major parts particularly under high frequency condition. High-speed permanent magnet synchronous machines (HS-PMSM) have the benefits of high power density, high efficiency and wide speed range. Which causes the calculation for iron loss and copper loss in whole operating range complex. By analyzing the components and influencing factors of iron loss and copper loss in stator, we have deduced the calculation formula of iron loss and copper loss in whole operating range based on the analytical solution and finite element approach (EFA) solution. According to the calculation solution, taking the influence of operating temperature on the iron loss and copper loss into account, we propose a temperature correction factor and establish the calculation method for the iron loss and copper loss with temperature influences. Finally, by the conductor transposition, we restrain the circulating current under high-frequency operating condition.