A dynamic battery model and parameter extraction for discharge behavior of a valve regulated lead-acid battery

摘要

The dynamic model of a battery is necessary for the appropriate real-time control during the charge/discharge process. The present paper considered the nonlinear Dynamic Equivalent Electric Circuit Model (DEECM) of a Valve Regulated Lead-Acid (VRLA) battery based on the data obtained through the experimentation and the available datasheet information. This work focuses on the identification of the nonlinear battery parameter during discharging and self-discharging with the influence of battery temperature. Experimentations are carried out on a 12V, 26Ah VRLA battery. Accordingly, experimental v-i characteristics of the battery are used to express the nonlinear model parameters as a function of measured battery current and estimated open-circuit voltage. The DEECM is validated through voltage response test with different steps of discharging current. The model results exactly match the experimental results for step increasing load with maximum error of +0.08% and for step decreasing load with maximum error of +0.4%.