Journal ArticleDOI
Optimal Control of the Gearshift Command for Hybrid Electric Vehicles
TLDR
The control algorithm is developed based on the combination of dynamic programming and Pontryagin's minimum principle to optimally control the discrete gearshift command, in addition to the continuous power split between the internal combustion engine and the electric machine.Abstract:
This paper proposes a design method for the energy management strategy to explore the potential fuel saving of a hybrid electric vehicle (HEV) equipped with an automated manual transmission. The control algorithm is developed based on the combination of dynamic programming (DP) and Pontryagin's minimum principle (PMP) to optimally control the discrete gearshift command, in addition to the continuous power split between the internal combustion engine and the electric machine. The proposed method outperforms DP in terms of computational efficiency, being 171 times faster, without loss of accuracy. Simulation results for a middle-sized HEV on the New European Drive Cycle show that, to further optimize the gearshift strategy, an additional fuel saving of 20.3% can be reached. Furthermore, with the start-stop functionality available, it is shown that the two-point boundary-value problem following from PMP cannot be solved with sufficient accuracy without loss of optimality. This means that the finding of a constant value for the Lagrange multiplier while satisfying the battery state-of-energy (SOE) at the terminal time is not always guaranteed. Therefore, an alternative approach of SOE feedback control to adapt the Lagrange multiplier is adopted. The obtained results are very close to the globally optimal solution from DP. Simulation results, including the start-stop functionality, show that the relative fuel saving can be up to 26.8% compared with the case of a standard gearshift strategy.read more
Citations
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Journal ArticleDOI
Control of connected and automated vehicles: State of the art and future challenges
TL;DR: In this paper, the authors introduce a control and planning architecture for CAVs, and surveys the state of the art on each functional block therein; the main focus is on techniques to improve energy efficiency.
Journal ArticleDOI
Convex Optimization for the Energy Management of Hybrid Electric Vehicles Considering Engine Start and Gearshift Costs
TL;DR: In this article, a combination of deterministic dynamic programming (DP) and convex optimization is proposed to solve the energy management problem for hybrid electric vehicles (HEVs) with engine start and gearshift costs.
Journal ArticleDOI
Optimal Energy Management for HEVs in Eco-Driving Applications Using Bi-Level MPC
TL;DR: This paper uses bi-level methodology to reduce computational time and simplify the hybrid optimal problem by decoupling its components into two subproblems, and provides an explicit solution of the optimal torque split ratio and gear shift schedule by combining Pontryagin's minimum principle and numerical methods in the framework of MPC.
Posted Content
Control of Connected and Automated Vehicles: State of the Art and Future Challenges
TL;DR: A control and planning architecture for CAVs is introduced, and the state of the art on each functional block therein is surveyed; the main focus is on techniques to improve energy efficiency.
Journal ArticleDOI
Analytic Solutions to the Dynamic Programming Subproblem in Hybrid Vehicle Energy Management
TL;DR: A local approximation of the gridded cost-to-go is used to derive an analytic solution for the optimal torque split decision at each point in the time and state grid, indicating that computation time can be reduced by orders of magnitude with only a slight degradation in simulated fuel economy.
References
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Journal ArticleDOI
Power management strategy for a parallel hybrid electric truck
TL;DR: The design procedure starts by defining a cost function, such as minimizing a combination of fuel consumption and selected emission species over a driving cycle, and dynamic programming is utilized to find the optimal control actions including the gear-shifting sequence and the power split between the engine and motor while subject to a battery SOC-sustaining constraint.
Book
Vehicle Propulsion Systems: Introduction to Modeling and Optimization
Lino Guzzella,Antonio Sciarretta +1 more
TL;DR: In this article, the authors present IC-engine-based and fuel-cell-based propulsion systems for vehicle energy and fuel consumption, as well as a case study of case studies and optimal control theory.
Journal ArticleDOI
Control of hybrid electric vehicles
Antonio Sciarretta,Lino Guzzella +1 more
TL;DR: In this paper, the authors analyzed two approaches, namely, feedback controllers and ECMS, which can lead to system behavior that is close to optimal, with feedback controllers based on dynamic programming.
Journal ArticleDOI
Optimal control of parallel hybrid electric vehicles
TL;DR: A model-based strategy for the real-time load control of parallel hybrid vehicles is presented and a suboptimal control is found with a proper definition of a cost function to be minimized at each time instant.
Journal ArticleDOI
Control Strategies for Hybrid Electric Vehicles: Evolution, Classification, Comparison, and Future Trends
TL;DR: This paper classifies and extensively overviews the state-of-the-art control strategies for HEVs, establishing a basis for comparing available methods and helping devoted researchers choose the right track.