Experimental Evaluation on Power Loss of Coreless Double-side Permanent Magnet Synchronous Motor/Generator Applied to Flywheel Energy Storage System

  • Kim, Jeong-Man (Dept. of Electrical Engineering, Chungnam National University) ;
  • Choi, Jang-Young (Dept. of Electrical Engineering, Chungnam National University) ;
  • Lee, Sung-Ho (Korea Institute of Industrial Technology)
  • Received : 2016.02.05
  • Accepted : 2016.08.31
  • Published : 2017.01.02


This paper deals with the experimental evaluation on power loss of a double-side permanent magnet synchronous motor/generator (DPMSM/G) applied to a flywheel energy storage system (FESS). Power loss is one of the most important problems in the FESS, which supplies the electrical energy from the mechanical rotation energy, because the power loss decreases the efficiency of energy storage and conversion of capability FESS. In this paper, the power losses of coreless DPMSM/G are separated by the mechanical and rotor eddy current losses in each operating mode. Moreover, the rotor eddy current loss is calculated by the 3-D finite element analysis (FEA) method. The analysis result is validated by separating the power loss as electromagnetic loss and mechanical loss by a spin up/down test.


Supported by : Chungnam National University


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