State of Charge Estimation Using a Nonlinear Autoregressive with Exogenous Input Neural Network

Among different methods that can be used to estimate the State of Charge of a battery in a dynamic profile, the data-driven method based on Neural Network (NN) is one of the most promising. This work investigates for dynamic automotive applications a time-recurrent Neural Network, such as Nonlinear Autoregressive with Exogenous Input Neural Network, to analyze its performance using two different battery datasets. Initially, tests that comprehend current, voltage, and temperature as input data have been performed. In the same step, a sensitivity analysis for three different timesteps has been investigated. In the following step, interpolation and extrapolation processes run on different battery temperature cycles have been considered. The third phase of this work introduced noise in input data to replicate a real-life case with its problems and finally, in the last step, it has been provided a generalization of the process, where the test datasets were different from the training ones. Throughout all the steps, NARX-NN shows good performances together with relatively low computational time.