ESTIMATION OF THE STATE OF CHARGE FOR LI-ION BATTERY DISCHARGE

• Main Authors: Ting-Tsai Wu, 吳丁財
• Other Authors: Chung-Chun Kung
• Format: Others
• Language: en_US
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/ns5sv7

碩士 === 大同大學 === 電機工程學系(所) === 102 === In today’s society, portable electric devices are more popular. So what kind of battery it used very important. Rechargeable Li-ion battery fit portable electric devices required. But the behavior of battery is difficult to predict. So battery management system (BMS) became an important course. It provided for management, monitoring, and diagnosis optimum performance of a battery. And measurement of SOC is one basis function of the BMS, which indicates the remaining charge of the battery so that users can be reminded to charge the battery prior to its depletion. In this thesis, we want to estimate the SOC for Li-ion battery. Therefore the state of Li-ion battery represent by an equivalent circuit model (ECM). However, in order to obtain ECM parameters we designed some experiments. And the experimental data using a first order least square method to fit these and then to get the ECM parameters. Then, we substitute these ECM parameters into state-space equation to estimate the SOC. Finally we will compare with the SOC estimator for Li-ion battery by the fuzzy C-regression model to validate effectiveness of the proposed method.