Research on Torque Distribution Strategy for ISG Hybrid Electric Cars

Based on the configuration and working state analysis of the ISG hybrid electric cars, the torque distribution strategy of a hybrid system is designed to delineate the maximum and minimum work torque curves of the engine, achieve optimization of engine’s range so as to make sure the target torque of the engine and ISG motor, and finally through the calibrated driving characteristics MAP and battery SOC state to achieve the calculation of total vehicle torque demand. Taking the Hafei Saibao ISG hybrid car as a test model, the test of fuel economy and emissions carried out under specific conditions showed that using the torque distribution strategy has increased by 12.8 % of the ISG hybrid car fuel economy and improved emissions performance to some extent compared to the traditional Hafei Saibao cars.

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Optimization of Economy Shift Schedule for Automated Mechanical Transmission in a Parallel Hybrid Electric Vehicle

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.260-261.331 ◽

2012 ◽

Vol 260-261 ◽

pp. 331-336

Author(s):

Zhen Tong Liu ◽

Hong Wen He ◽

Wei Qing Li

Keyword(s):

Electric Vehicle ◽

Hybrid Electric Vehicle ◽

Mechanical Transmission ◽

Torque Distribution ◽

Power Train ◽

Distribution Strategy ◽

Parallel Hybrid Electric Vehicle ◽

Shift Schedule ◽

Parallel Hybrid ◽

Hybrid Electric

Power train of hybrid electric vehicle (HEV) equipped with automated mechanical transmission (AMT) is made up of engine, electric motor, batteries and propulsion system. Shift schedule can’t be worked out with the same way of conventional AMT vehicle. Based on the optimal torque distribution strategy and analysis of the driving efficiency for parallel hybrid electric vehicle (PHEV), a new economy shift schedule for PHEVs equipped with AMT is proposed to maximize the driving efficiency. The MATLAB/CRUISE co-simulation results show that the proposed shift schedule can more efficiently improve the fuel economy performance.

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Optimal torque distribution strategy for dual traction motors in a series hybrid electric intra-city bus

International Journal of Heavy Vehicle Systems ◽

10.1504/ijhvs.2017.10001848 ◽

2017 ◽

Vol 24 (1) ◽

pp. 18

Author(s):

Daebong Jung ◽

Kyoungdoug Min ◽

Minjae Kim

Keyword(s):

Torque Distribution ◽

Distribution Strategy ◽

City Bus ◽

Traction Motors ◽

Hybrid Electric

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Computationally Efficient Energy Management in Hybrid Electric Vehicles Based on Approximate Pontryagin’s Minimum Principle

World Electric Vehicle Journal ◽

10.3390/wevj11040065 ◽

2020 ◽

Vol 11 (4) ◽

pp. 65

Author(s):

Fengqi Zhang ◽

Lihua Wang ◽

Serdar Coskun ◽

Yahui Cui ◽

Hui Pang

Keyword(s):

Energy Management ◽

Fuel Economy ◽

Piecewise Linear ◽

Minimum Principle ◽

Engine Fuel ◽

Pontryagin’S Minimum Principle ◽

Torque Distribution ◽

Computation Efficiency ◽

Pontryagin's Minimum Principle ◽

Hybrid Electric

This article presents an energy management method for a parallel hybrid electric vehicle (HEV) based on approximate Pontryagin’s Minimum Principle (A-PMP). The A-PMP optimizes gearshift commands and torque distribution for overall energy efficiency. As a practical numerical solution in PMP, the proposed methodology utilizes a piecewise linear approximation of the engine fuel rate and state of charge (SOC) derivative by considering drivability and fuel economy simultaneously. Moreover, battery aging is explicitly studied by introducing a control-oriented model, which aims to investigate the effect of battery aging on the optimization performance in the development of the HEVs. An approximate energy management strategy with piecewise linear models is then formulated by the A-PMP, which targets a better performance for the Hamiltonian optimization. The gearshift map is extracted from the optimal results in the standard PMP to hinder frequent gearshift by considering both drivability and fuel economy. Utilizing an approximated Hamilton function, the torque distribution, gearshift command, and the battery aging degradation are jointly optimized under a unified framework. Simulations are performed for dynamic programming (DP), PMP, and A-PMP to validate the effectiveness of the proposed approach. The results indicate that the proposed methodology achieves a close fuel economy compared with the DP-based optimal solution. Moreover, it improves the computation efficiency by 50% and energy saving by 3.5%, compared with the PMP, while ensuring good drivability and fuel efficiency.

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A Comprehensive Study of Propulsion Torque Distribution for a Parallel Hydraulic Hybrid Heavy Bus

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.365-366.454 ◽

2013 ◽

Vol 365-366 ◽

pp. 454-458

Author(s):

Zhong Liang Zhang ◽

Jie Chen

Keyword(s):

Fuel Economy ◽

Low Energy ◽

Optimal Operating ◽

Torque Distribution ◽

Operating Line ◽

Distribution Strategy ◽

Hydraulic Hybrid ◽

Frequent Switching ◽

Urban Bus ◽

Comprehensive Study

The purpose of this paper is to improve the fuel economy of a parallel hydraulic hybrid heavy bus. And an optimal distribution strategy of the propulsion torque was proposed based on engine working points of the conventional bus. The universal characteristics map of the engine was divided into three zones by the optimal operating line and the fuel contour CBF. The results indicated this strategy can not only overcome the low energy density disadvantage of the accumulator but also prohibit frequent switching between the engine and the pump/motor. The HHP can provide most of the required torque and make most working points of the engine around or on the optimal operating line. When the value of the fuel contour CBF is 213g/kw.h, the bus has the minimal fuel consumption in the typical urban bus cycle and the fuel economy of the engine improves 24.8% compared to the conventional bus.

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