Concurrent design of energy management and vehicle stability algorithms for a parallel hybrid vehicle using Dynamic Programming

Abstract

Abstract-In this paper, concurrent design of controllers for a vehicle equipped with a parallel hybrid powertrain is studied. Our work focuses on designing the two control algorithms, the energy management and the vehicle stability, concurrently which are traditionally considered separately. Dynamic Programming (DP) technique is used in order to obtain the optimal response trace for the controllers. In energy management strategy torque split ratio between engine and electric motor is used as a control signal. Additionally, in vehicle dynamics control strategy the torque split factor between front and rear axles is used as a control signal. Minimizing the fuel consumption and wheel slip is used as cost functions in energy management and vehicle dynamics control strategies respectively. Two dynamic problems are solved separately first and compared to the concurrent solution of the problems. Results show promising benefits can be obtained from the concurrent DP solution and rule extraction for designing better hybrid vehicle controllers.I.

Dynamic programming technique for optimizing fuel cell hybrid vehicles

“…Moreover, it is desirable for the SOC not to rise above 80% in-order to capture energy from regenerative braking. The battery non-linear charge and discharge efficiencies are considered from equation (13). The weights (w a , w b , w c ) are updated in-order to find the minimum cost for a certain set of weights.…”

“…The authors introduced a penalty factor on the battery state of charge (SOC) where the cost increases cubically if SOC is outside the limit margin. Dokuyucu et al [13] formulated a controller based on dynamic programming to find the torque split between the ICE and the electric motor. The control signal considered is the battery SOC which is bounded between 0.4 and 0.7.…”

Concurrent Design of Energy Management and Vehicle Traction Supervisory Control Algorithms for Parallel Hybrid Electric Vehicles

“…In (20), f em (SOC k , TSR k ) is a function used for calculating the current state based on the simple model formulation. Since we are only concerned with the EM side of the problem, the RRSR is taken as constant (RRSR = x 2 k = 0.5).…”

“…The effect of coupling in control problems is also observed in [19]. The strong interaction between these two control problems is outlined in [20]. The remainder of this paper is organized as follows: In Section II, vehicle models used for controller development and controller verification are explained.…”