| Title |
A Research on the Estimation Method for the SOC of the Lithium Batteries Using AC Impedance |
| Authors |
Jong-Hak Lee ; Sang-Hyun Kim ; Wook Kim ; Woojin Choi |
| Keywords |
Lithium Polymer Battery; State-of-Charge; AC Impedance; Eletrochemical Impedance Spectroscopy; Time Constant |
| Abstract |
This paper suggests a standstill estimator to accurately identify induction motor (IM) parameters necessary for the vector control. A mathematical model that faithfully represents the general skin effect is introduced. Then, two exciting signals with a different frequency are sequentially injected to track the parameters based on the skin effect of the rotor bar. Little knowledge of the unknown motor allows the proposed methodology to employ a closed-loop control of an injected current, rather than open-loop voltage injection approaches. Subsequently, this control scheme proactively prevents electrical accidents resulting from an inadequate open-loop voltage injection. We develop a specialized offline commissioning test to compensate the phase delay resulting from the drive, which significantly affects the precision of the IM parameters. The effectiveness of the identification technique is validated by means of experiments performed on the three different IMs. |