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To fulfil the CO2 emission reduction targets of the European Union (EU), heavy-duty (HD) trucks need to operate 15% more efficiently by 2025 and 30% by 2030. Their electrification is necessary as conventional HD trucks are already optimized for the long-haul application. The resulting hybrid electric vehicle (HEV) truck gains most of the fuel saving potential by the recuperation of potential energy and its consecutive utilization. The key to utilizing the full potential of HEV-HD trucks is to maximize the amount of recuperated energy and ensure its intelligent usage while keeping the operating point of the internal combustion engine as efficient as possible. To achieve this goal, an intelligent energy management strategy (EMS) based on ECMS is developed for a parallel HEV-HD truck which uses predictive discharge of the battery and adaptive operating strategy regarding the height profile and the vehicle mass. The presented EMS can reproduce the global optimal operating strategy over long phases and lead to a fuel saving potential of up to 2% compared with a heuristic strategy. Furthermore, the fuel saving potential is correlated with the investigated boundary conditions to deepen the understanding of the impact of intelligent EMS for HEV-HD trucks. [ABSTRACT FROM AUTHOR]

In this paper, we propose a multilayer perceptron-based recognition method for driving cycles of commercial vehicles. Our method solves the problem of identifying the type of driving cycle for commercial vehicles, and improves the efficiency and sustainability of road traffic. We collect driving condition data of 106,200 km long-distance commercial vehicles to validate our method. We pre-proceed six kinds of quantitative features as the data description; these are average speed, gear ratio, and accelerator pedal opening. Our model includes an input layer, hidden layers, and an output layer. The input layer receives and processes the input as low-dimensional features. The hidden layers consist of the feature extraction module and class regression module. The output layer projects extracted features to the classification space and computes the likelihood for each type. We achieve 99.83%, 97.85%, and 99.40% on the recognition accuracy for the expressway driving cycle, the suburban road driving cycle, and the urban road driving cycle, respectively. The experimental results demonstrate that our model achieves better results than the statistical method using Naive Bayes. Moreover, our method utilizes the data more efficiently and thus gains a better generalization performance. [ABSTRACT FROM AUTHOR]

For series hybrid electric vehicles, due to the limitation of engine operating characteristics, speed regulation is usually performed using discrete operating points. This leads to the problem of mixed integer programming when solving energy management problem. In this paper, an analytical method with strong real-time performance and small computational load is proposed. First, an intelligent cycle recognition system is designed. It can cluster driving cycles offline based on the probability distribution of the required power and efficiently recognize unknown driving cycles online. Then the analytical expression of power distribution is derived, and the selection scheme of engine operating point is given. Finally, the required power information obtained from the clustering is substituted into the analytical expression. The specific values of the corresponding analytical solutions for each type are computed offline. When facing unknown conditions, this method can match the power distribution scheme quickly once the driving cycle is recognized. The results of the simulation and hardware-in-loop experiments demonstrate that this method can effectively control the SOC trajectory and allocate power more optimally. Compared to the benchmark method, the proposed strategy improves the fuel economy by 5.52 % and 7.49 % in two cases, and the computational efficiency is significantly enhanced. • An intelligent driving cycle recognition system using deep clustering is designed. • An improved fully analytical ECMS is proposed. • Coordinative optimization for engine operation and power flow of SHEV. • The control performance is validated both in simulation and hardware-in-loop test. [ABSTRACT FROM AUTHOR]

Hybrid electric vehicles (HEVs) are considered the most practical option for reducing emissions and fuel consumption of conventionally powered vehicles. Energy management strategies (EMSs) are the core technology of HEVs because of decreasing the cost of the system and limiting its negative effects. Equivalent consumption minimization strategy (ECMS) can achieve instantaneous optimal control and has attracted attention in recent years. In this study, an adaptive equivalent consumption minimization strategy (A-ECMS) based on driving cycle recognition is constructed for a parallel HEV. First, select the standard driving cycle and analyze its characteristic parameters. And then training learning vector quantization (LVQ) neural network-based driving cycle recognizer to achieve an average of 98% accuracy. At last, the optimal equivalent factor (EF) is selected for ECMS by recognizing the current driving cycle. It is jointly simulated and analyzed by AVL CRUISE and MATLAB/Simulink software under NEDC and CHTC-LT driving cycle. The results show that compared with the logic-based EMS, in the NEDC driving cycle the 100 km fuel consumption of A-ECMS decreases by 3.8%, and the battery state of charge (SOC) increases by 1.1%. In the CHTC-LT driving cycle, fuel economy improves by 3.6%, proving the superiority of the A-ECMS.

To fulfil the CO2 emission reduction targets of the European Union (EU), heavy-duty (HD) trucks need to operate 15% more efficiently by 2025 and 30% by 2030. Their electrification is necessary as conventional HD trucks are already optimized for the long-haul application. The resulting hybrid electric vehicle (HEV) truck gains most of the fuel saving potential by the recuperation of potential energy and its consecutive utilization. The key to utilizing the full potential of HEV-HD trucks is to maximize the amount of recuperated energy and ensure its intelligent usage while keeping the operating point of the internal combustion engine as efficient as possible. To achieve this goal, an intelligent energy management strategy (EMS) based on ECMS is developed for a parallel HEV-HD truck which uses predictive discharge of the battery and adaptive operating strategy regarding the height profile and the vehicle mass. The presented EMS can reproduce the global optimal operating strategy over long phases and lead to a fuel saving potential of up to 2% compared with a heuristic strategy. Furthermore, the fuel saving potential is correlated with the investigated boundary conditions to deepen the understanding of the impact of intelligent EMS for HEV-HD trucks.

With the increasing demand for battery electric buses, the dual-motor coupling powertrain (DMCP) shows great advantages, but it makes the energy optimization problem more complex. To solve the hybrid system optimization problem, a stochastic model predictive control (SMPC) method is proposed to exploit the potential performance of DMCP, where the most critical issue is to improve the prediction accuracy and handle the uncertainties. After analyzing the typical velocity profiles, statistical properties are used to develop a novel Signed Markov Chain Monte Carlo (SMCMC) method that can enhance the accuracy of velocity prediction by more than 50%, compared to conventional Markov Chain methods. Next, considering the uncertainties present in various driving scenarios, the development of driving cycle recognition model based on fuzzy logic control (FLC) is introduced; this method permits to identify the current category of driving cycle rapidly. Then, dynamic programming (DP) is adopted to solve the rolling optimization problems in each finite horizon online, including necessary constraints of dynamic response. Finally, simulation results demonstrate that the proposed energy management strategy can address various daily driving cycles well, and can improve the energy performance by 6% under a generalized combination of driving conditions compared to preliminary rule-based control.

Aiming at the problems inherent in the traditional fuzzy energy management strategy (F-EMS), such as poor adaptive ability and lack of self-learning, a neural network fuzzy energy management strategy (NNF-EMS) for hybrid electric vehicles (HEVs) based on driving cycle recognition (DCR) is designed. The DCR was realized by the method of neural network sample learning and characteristic parameter analysis, and the recognition results were considered as the reference input of the fuzzy controller with further optimization of the membership function, resulting in improvement in the poor pertinence of F-EMS driving cycles. The research results show that the proposed NNF-EMS can realize the adaptive optimization of fuzzy membership function and fuzzy rules under different driving cycles. Therefore, the proposed NNF-EMS has strong robustness and practicability under different driving cycles. [ABSTRACT FROM AUTHOR]

Taking a parallel hybrid bus as research object， four kinds of typical working condition models were established， and the ant colony optimization algorithm was used to optimize the charge and discharge equivalent factor for each working condition in minimal equivalent fuel consumption control strategy. The relation between road gradient and adjustment of battery SOC target range was analyzed， and the corresponding gradient adaptive module was designed. A control strategy optimization method was proposed based on driving cycle recognition for HEV. The results of simulation and comparison analysis under typical working conditions showed that the method has very well driving condition adaptability， and its fuel economy is significantly higher than that of other several typical HEV control strategies. [ABSTRACT FROM AUTHOR]

Hybrid electric vehicles present a promising approach to reduce fuel consumption and carbon dioxide emissions. The core technology of hybrid electric vehicles is an energy management strategy to distribute torque between the engine and the electric motor. This study presents an optimized energy management strategy based on real-time control. The operation platform of the control system is based on the dSPACE/simulator, which is a commercial hardware closed-loop system. First, an energy management strategy is built by using an empirical analysis method. To reduce fuel consumption further and to maintain the balance of the battery state of charge, dynamic programming is introduced to achieve the best fuel economy. Optimal gear shifting and engine torque control rules are then extracted into a rule-based control algorithm. Meanwhile, genetic algorithm is introduced to optimize the mode transition rules and the engine torque under parallel mode through an iterative method by defining a cost function over specific driving cycles. Second, a driving cycle recognition algorithm is built to obtain the optimization result over different driving cycles. The real vehicle model is verified by using a hardware-in-the-loop simulator in a virtual forward-facing simulation environment. The energy management strategy uses a code generation technology in the TTC200 controller to achieve vehicle real-time communication. Simulation results demonstrate that the real-time energy management strategy can coordinate the overall hybrid electric powertrain system to optimize fuel economy over different driving cycles and to maintain the battery state of charge. [ABSTRACT FROM AUTHOR]

A novel dual-motor electric vehicle (DMEV) with superior energy efficiency depends on its diverse operation modes. However, the operation mode shift will lead to the ride comfort problem owing to the uncertainty of the actual driving cycles. To address this issue, bi-objective optimization strategy-based driving cycle-aware bias coefficients is proposed to tradeoff between energy consumption and shift shock. Firstly, the system efficiency and the shift shock models are developed for DMEV. The torque distribution coefficient is defined to be a control variable for the bi-objective optimization of system efficiency and ride comfort. Furthermore, this study combines the bi-objective optimization algorithm with driving cycle recognition to introduce the optimized bias coefficient to determine the driving cycle-aware bias coefficient for the mentioned optimized target objectives. Then, the non-dominated sorting genetic algorithm-II is applied for the bi-objective optimization, which produces a group of the Pareto solutions including the energy consumption and shift shock. Moreover, the proposed bi-objective optimization strategy is conducted by controlling the optimized bias lines for the optimal torque distribution of the novel dual-motor powertrain system. Ultimately, numerous validations and comparisons demonstrate that the proposed strategy effectively accomplishes the trade-off optimization between energy consumption and shift shock in real-time. • The adaptive tradeoff optimization of energy consumption and shift shock is proposed. • The adaptive optimized bias coefficient is attained by the driving cycle recognition. • A novel driving cycle-aware bi-objective optimization strategy is formulated. • The proposed strategy achieves great tradeoff performance in various driving cycles. [ABSTRACT FROM AUTHOR]

By considering the effect of the driving cycle on the energy management strategy (EMS), a fuzzy EMS based on driving cycle recognition is proposed to improve the fuel economy of a parallel hybrid electric vehicle. The EMS is composed of driving cycle recognition and a fuzzy torque distribution controller. The current driving cycle is recognized by learning vector quantization in driving cycle recognition. The torque of the engine and the motor is controlled by a fuzzy torque distribution controller based on the required torque of the hybrid powertrain and the battery state of charge. The membership functions and rules of the fuzzy torque distribution controller are optimized simultaneously by using particle swarm optimization. Based on the identification results of driving cycle recognition, the fuzzy torque distribution controller selects the corresponding membership function and rule to control the hybrid powertrain. The simulation research based on ADVISOR demonstrates that this EMS improves fuel economy more effectively than fuzzy EMS without driving cycle recognition. [ABSTRACT FROM AUTHOR]