A Study on Efficiency and Power factor Increase of Spoke type 45kW MG-PMSM

In order to solve the energy shortage and environmental problems, a railway system is proposed among transportation. Among them, the tram, which has advantages such as reasonable initial construction cost and door-to-door connectivity, is attracting attention as a new transportation system. However, when using a tram, the use of a vertical gear is inevitable due to the use of a low-floor bogie, which has a complicated structure and difficult maintenance. In addition, the direct contact method of the vertical gear has several problems. Therefore, in order to solve these problems, the magnetic-geared permanent magnet synchronous motor (MGPMSM), which consists of a magnetic gear and a traction motor as one system is proposed. A spoke type MG-PMSM with advantageous torque characteristics is designed to satisfy the low-speed and high-torque characteristics during initial starting of railway. In addition, a method for improving efficiency is additionally proposed.