Power-split HEV Research Articles

Energy-efficient powertrain control of an automated and connected power-split HEV in an urban environment

Abstract The ongoing trend toward powertrain electrification and vehicle automation enables the exploitation of additional energy saving potential through the joint optimization of the driving trajectory and the hybrid management. To tackle this complex control task within the E-COSM 2021 Benchmark Challenge, we combine a GLOSA algorithm generating a uniform speed profile with an optimization-based hybrid powertrain controller employing an equivalent consumption minimization strategy.

A New Energy Management Strategy for Multimode Power-Split Hybrid Electric Vehicles

Among the hybrid electric vehicle categories, the multimode power-split allows to fully exploit the advantages related to the powertrain electrification. However, together with the increased flexibility, it comes with greater difficulty in defining an effective control strategy, both in terms of predicted fuel consumption and computational cost. To overcome the limits of the most diffused energy management strategies, slope-weighted energy-based rapid control analysis (SERCA) has been recently proposed. Nevertheless, so far, the algorithm has been applied to powertrains characterized by two operative modes solely. In this paper, we first present the inconsistency of SERCA applied to the whole set of multimode power-split arrangements. Subsequently, after correlating this divergence to the mode selection process, to overcome this draft, we introduce a novel strategy called SERCA+. This algorithm is proven to be robust and to achieve results close to the optimum benchmark with an insignificant increase in computational cost. Therefore, SERCA+ could potentially find application in design methodologies for multimode power-split HEVs to accelerate the overall vehicle design process.

Simulation Analysis on the Rule-based Energy Management of a Power-split Hybrid Electric Vehicle

A power-split hybrid electric vehicle has the advantages of both series and parallel HEVs by using a planetary gear to combine or split the power of an engine, a motor and a generator. Due to the different operation modes of a power-split HEV, finding a near optimal and practical energy management control strategy is quite necessary. The paper proposes a kind of the ruled-based strategy of a power-split HEV, which can be applied to take simulation analysis for practical driving cycle. The strategy is made up of the optimal distribution strategy of engine operating points, the control methodology of motor torque, the strategy of generator and the charge sustaining-based battery control, respectively. The simulation results compared with the results of the DP-based optimal algorithm show the ruled-based control strategy is valid.

Hierarchical Energy Management for Power-Split Plug-In HEVs Using Distance-Based Optimized Speed and SOC Profiles

This paper proposes a distance-based two-stage energy management strategy for power-split plug-in hybrid electric vehicles (PHEVs). One stage is for long-term optimization and the other is for short-term adaptation to actual traffic conditions. Energy consumption in PHEVs depends on the characteristics of the drivetrain as well as the operating conditions such as power demands and their split. Thus, prior to departure, the operating conditions for a whole trip are optimized for the drivetrain characteristics and trip information, which generates optimal speed and state-of-charge profiles. While driving, the operating conditions are adapted to current traffic conditions for a short horizon on the basis of long-term optimization results. In consideration of the changeability of traffic conditions, the proposed energy management strategy is performed in a distance domain, which localizes the effects of changes in traffic conditions on the long-term optimization results. Therefore, this distance-based two-stage strategy improves the balance between the optimality and the real-time computing time, which is suitable for online management. A model for the propulsion system in a PHEV and the energy management strategy were formulated in a distance domain. An estimation of distribution algorithm was used for long-term optimization and local adaptation.

Optimal Design of Power-Split HEVs Based on Total Cost of Ownership and CO2 Emission Minimization

An optimal design toolbox for hybrid electric vehicles has been developed and applied to three different vehicle segments (a compact vehicle, a small SUV and a medium-size SUV) for two separate power-split hybrid layouts, both equipped with a diesel engine. One layout features a (3gTR) whereas the other lacks of the additional 3-gear transmission. The toolbox combines the optimization of the vehicle design to that of the control strategy and is based on the minimization of the total cost of ownership (TCO) over the vehicle lifetime. The tool still retains the capability of complying with different performance and emission constraints. The identified optimal designs have proved to lead to a reduction of the CO2 emissions by 50 to 55% and to a reduction of the TCO by 9 to 10% if compared to the conventional vehicle. Such results held for all classes of vehicle. A cost-benefit analysis and a break-even analysis have also been carried out. A mileage of 20,000 km/year over an urban driving scenario has turned out to possibly allow the driver to break even in about four years for the SUVs and in about six years for the compact vehicle. Finally, a linear correlation between the TCO and the specifications of the design components has been detected with a mean percentage error of about 0.1%. Such a correlation can be very helpful for vehicle design tasks.

Modeling and optimal energy management of a power split hybrid electric vehicle

With the combination of engine and two electric machines, the power split device allows higher efficiency of the engine. The operation modes of a power split HEV are analyzed, and the system dynamic model is established for HEV forward simulation and controller design. Considering the fact that the operation modes of the HEV are event-driven and the system dynamics is continuous time-driven for each mode, the structure of the controller is built and described with the hybrid automaton control theory. In this control structure, the mode selection process is depicted by the finite state machine (FSM). The multi-mode switch controller is designed to realize power distribution. Furthermore, the vehicle mode operations are optimized, and the nonlinear model predictive control (NMPC) strategy is applied by implementing dynamic programming (DP) in the finite prediction horizon. Comparative simulation results demonstrate that the hybrid control structure is effective and feasible for HEV energy management design. The NMPC optimal strategy is superior in improving fuel economy.

ゲインスケジューリングモデル予測制御によるHEVの燃費最適化

ゲインスケジューリングモデル予測制御によるHEVの燃費最適化

Modeling and Simulation of Power-Split Hybrid System

In this paper, A new type of power-split HEV system based on Ravigneaux Planetary Mechanism is introduced. Using AVL Cruise software established the hybrid passenger car simulation model. The energy management system control strategy based rules is also studied. The effectiveness of the control strategy for the vehicle is proved by UDDC driving cycle. According to the results, fuel consumption saving of five percent than that of the prototype.

Powertrain architectures of electrified vehicles: Review, classification and comparison

Increasingly stringent regulations and customers׳ demand for high fuel economy led to rapid developments of distinct alternative powertrain solutions, especially electrified vehicles. Fusion of electric machines into powertrain greatly diversifies powertrain architectures and enriches means to save energy. In this review work, conventional classification of hybrid electric vehicle (Series, Parallel and Power-split HEVs) is expanded to all electrified vehicles (xEV) by including Pure Electric Vehicle (PEV) as the fourth primary type of electrified powertrain architecture; In addition, electrification level of powertrain is analyzed and incorporated into new classification method as the second index; different variants of PEV, Series, Parallel and Power-split HEVs are presented with corresponding patents or products; more complex electrified powertrains are also illustrated by decomposing them into two or more of the four fundamental types and sub-types. This review work is based on comprehensive and up-to-date summary of current development in this field.

MODELLING AND CONTROL OF POWER-SPLIT HYBRID ELECTRIC VEHICLE USING FUZZY LOGIC METHOD

Nowadays, automotive manufactures increasingly have lead to development of hybrid vehicles due to energy consumption growing and increased emissions. the power-split hybrids due to the simultaneous using of speed and torque couplings has integrated advantage of series and parallel hybrid systems and minimize their disadvantages , however the power-split hybrids control strategy is far more complex than other types. Generally the control strategy tries to use the optimize operating point of HEV components such as ICE, TM, MG, batteries and etc. in this research the using of fuzzy logic control method is considered to increase optimize the power-split Hybrid components operation. The power-split HEVs model have been built with ADVISOR-Matlab/Simulink Software for an C class car based on TOYOTA Prius Model, and the simulation results showed significant improvements in fuel consumption and performance and as well as emissions

Power-Split Hybrid Electric Vehicle Energy Management Based on Improved Logic Threshold Approach

We design an improved logic threshold approach of energy management for a power-split HEV assisted by an integrated starter generator (ISG). By combining the efficiency map and the optimum torque curve of internal combustion engine (ICE) with the state of charge (SOC) of batteries, the improved logic threshold controller manages the ICE within its peak efficiency region at first. Then the electrical power demand is established based on the ICE energy output. On that premise, a variable logic threshold valueKis defined to achieve the power distribution between the ISG and the electric motor/generator (EMG). Finally, simulation models for the power-split HEV with improved logic threshold controller are established in ADVISOR. Compared to the equally power-split HEV with the logic threshold controller, when using the improved logic threshold controller, the battery power consumption, the ICE efficiency, the fuel consumption, and the motor driving system efficiency are improved.

Power-Split HEV Control Strategy Development with Refined Engine Transients

Power-Split HEV Control Strategy Development with Refined Engine Transients