Li-ion battery discharge emulator based on three-phase interleaved DC-DC boost converter

This paper presents a Li-ion battery discharge emulator. The proposed emulator is composed of a battery model and a three-phase interleaved DC-DC boost converter. The battery model used was found in the literature which consists of an electrical equivalent circuit (EEC) based on Thévenin and the Shepherd modified equation of open circuit voltage. This model is used taking into account the voltage drop caused by the EEC besides it has an accuracy of 2 resistor-capacitor (RC) networks. The Electrochemical Impedance Spectroscopy (EIS) is used to obtain these RC values. The output voltage waveforms generated by the battery emulator (simulations) are compared with the waveforms obtained from discharges of a real battery on a test bench (experimental tests). The results show that the simulations have errors of less than 1 % in replicating the steady and dynamic behavior for the output voltage of the real battery even with pulses of discharge currents greater than its nominal battery capacity.