The current tracing control for BSG motor field current based on sliding mode current observer

On the basis of traditional electric excitation synchronous motor, BSG motors, adopting the mixed excitation technique, are widely used in mild-hybrid electric vehicle applications, but the nonlinearities of BSG motor excitation winding driving circuit and a variety of interference outside the engine compartment make it difficult for conventional PWM strategy to achieve the optimal output current. In this paper, a sliding mode observer approach is proposed, utilizing advantages that including good control robustness to conduct online setting. Simulation and experimental results show that the method enhances the system´s self adaptive capacity, improves the startup performance of BSG-hybrid cars, and has good current tracking performance, and low costing.