Lithium-ion battery modeling under high-frequency ripple current for co-simulation of high-power DC-DC converters

Studying the output response of lithium-ion batteries under high-frequency ripple current is important for the co-simulation and optimal design of high-power DC-DC converters using IGBTs. However, this influence has not been sufficiently investigated. In this paper, seven equivalent circuit models which include integer and fractional order models are used to simulate the high frequency characteristics of lithium-ion batteries. Thirteen experiments are designed and implemented on three test platforms, including a self-designed DC-DC platform for triangular wave. These experiments consist of average currents of different amplitudes, ripple currents of different types, amplitudes and frequencies. Unlike previous research, the current excitation and voltage response of high frequency ripple are obtained by separating the short and long time scale signals. The equivalent circuit model components are selected based on the frequency domain characteristics of the impedance spectrum. The HMPSO method is employed to implement the parameter identification and simulation analysis of the high frequency model under time domain data. By contrast, the first-order RL model is selected as the preferred choice through modeling and co-simulation. The complexity of the model and co-simulation time is reduced while maintaining voltage accuracy. For the case presented in this paper, the co-simulation time of R(RL) can be reduced by 11.3 % and 30.2 % compared to the RL and R(RL)(RL) models.