SIMULINK based hardware-in-the-loop rapid prototyping of an electric vehicle battery balancing controller

Large strings of battery cells require a conditioning system to avoid parameter divergence, especially for Lithium based battery cells. The development procedure of a real time, central-control system with a high control loop rate, sophisticated battery internal state estimation, low cost and short developing time is presented. The method is based on a real plant and controller emulating system. The emulating system is implemented using a standalone PC, running a Real-Time SIMULINK environment. The approach does not require a computationally powerful DSP, or ECU, no additional programming skills are needed, and it could be implemented using software and hardware readily available in most laboratories. The computationally intensive algorithm used in this study was a sigma-point Kalman filter SOC estimator. Validation of the method was carried out on a battery pack consisting of 21 series 25 Ah Li-ion NMC cells, and a total conditioning power of 650 W.