SOC Observer based on Piecewise Linear Modeling for Lithium-Polymer Battery

구간선형 모델링 기반의 리튬-폴리머 배터리 SOC 관측기

  • Received : 2015.06.04
  • Accepted : 2015.07.01
  • Published : 2015.08.20


A battery management system requires accurate information on the battery state of charge (SOC) to achieve efficient energy management of electric vehicle and renewable energy systems. Although correct SOC estimation is difficult because of the changes in the electrical characteristics of the battery attributed to ambient temperature, service life, and operating point, various methods for accurate SOC estimation have been reported. On the basis of piecewise linear (PWL) modeling technique, this paper proposes a simple SOC observer for lithium-polymer batteries. For performance evaluation, the SOC estimated by the PWL SOC observer, the SOC measured by the battery-discharging experiment and the SOC estimated by the extended Kalman filter (EKF) estimator were compared through a PSIM simulation study.


Supported by : 홍익대학교


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