Aishwarya Panday

A Review of Optimal Energy Management Strategies for Hybrid Electric Vehicle

Presence of an alternative energy source along with the Internal Combustion Engine (ICE) in Hybrid Electric Vehicles (HEVs) appeals for optimal power split between them for minimum fuel consumption and maximum power utilization. Hence HEVs provide better fuel economy compared to ICE based vehicles/conventional vehicle. Energy management strategies are the algorithms that decide the power split between engine and motor in order to improve the fuel economy and optimize the performance of HEVs. This paper describes various energy management strategies available in the literature. A lot of research work has been conducted for energy optimization and the same is extended for Plug-in Hybrid Electric Vehicles (PHEVs). This paper concentrates on the battery powered hybrid vehicles. Numerous methods are introduced in the literature and based on these, several control strategies are proposed. These control strategies are summarized here in a coherent framework. This paper will serve as a ready reference for the researchers working in the area of energy optimization of hybrid vehicles.

Energy management strategy for hybrid electric vehicles using genetic algorithm

Energy management strategies significantly influence the fuel efficiency of hybrid electric vehicles. They play a crucial role in splitting the power between two sources, namely, engine and the battery. Power split between these two intelligently will enhance the fuel economy and regulates the power flow. Power split between engine and motor depends on state of charge (SOC) of battery, power required at the wheels, and engines operating range. Various parameters of power train are considered to control the toggling between engine and battery. To achieve parameter optimization, genetic algorithm is practised to realize the optimal performance. A modified SOC estimation algorithm is employed with different battery models to analyze the vehicle performance. The battery models with internal resistance only and combinations of 1RC and 2RC are used. Parameter optimization over different battery models with modified SOC estimation algorithm is performed in different situations and a comparative study is elaborated.

Energy Management Strategy Implementation for Hybrid Electric Vehicles Using Genetic Algorithm Tuned Pontryagin’s Minimum Principle Controller

To reduce apace extraction of natural resources, to plummet the toxic emissions, and to increase the fuel economy for road transportation, hybrid vehicles are found to be promising. Hybrid vehicles use batteries and engine to propel the vehicle which minimizes dependence on liquid fuels. Battery is an important component of hybrid vehicles and is mainly characterized by its state of charge level. Here a modified state of charge estimation algorithm is applied, which includes not only coulomb counting but also open circuit voltage, weighting factor, and correction factor to track the run time state of charge efficiently. Further, presence of battery and engine together needs a prevailing power split scheme for their efficient utilization. In this paper, a fuel efficient energy management strategy for power-split hybrid electric vehicle using modified state of charge estimation method is developed. Here, the optimal values of various governing parameters are firstly computed with genetic algorithm and then fed to Pontryagin’s minimum principle to decide the threshold power at which engine is turned on. This process makes the proposed method robust and provides better chance to improve the fuel efficiency. Engine efficient operating region is identified to operate vehicle in efficient regions and reduce fuel consumption.

Thermoelectric modeling and online SOC estimation of Li-ion battery for Plug-In Hybrid Electric Vehicles

The increasing oil price, energy demand, and environmental concern are leading to a global switch towards Plug-In Hybrid Electric Vehicles (PHEVs). In a PHEV, Li-ion battery is considered as the primary propelling source. Therefore, an accurate battery model is required to predict the I-V characteristic and dynamic behavior of a battery. This paper presents a highly effective thermoelectric model of Li-ion battery developed in Simulink. An algorithm is proposed for estimation of state of charge (SOC) and open circuit voltage (OCV) adaptively to notify the exact SOC level for better utilization of battery power and optimal vehicle performance. Thermal behavior of Li-ion battery is investigated for wide temperature range and its effect on resistance, capacity, and OCV is recorded. The minimum SOC level to which battery can get depleted is calculated using gradient method. The proposed simulation results are analyzed with those of earlier models and found to be better.

Fuel efficiency optimization of input-split hybrid electric vehicle using DIRECT algorithm

For cleaner and greener future, Hybrid vehicle has been accepted as best practical applications for transportation. The presence of two power sources, i.e. engine and battery in hybrid electric vehicles makes it necessary to intelligently split the power for lesser fuel consumption. An intelligent power management strategy is developed to fulfil on road power demand with good fuel economy. This article uses DIRECT method to control toggling between the engine and battery to reduce the overall liquid fuel consumption. The battery charge is utilized effectively without deteriorating its health. The control strategy is based on the optimization of vital parameters such as state of charge in the battery, engine idle speed, engine on duration and power demand. Numerous simulations are executed on the advanced vehicle simulator (ADVISOR) to authenticate the feasibility of the proposed controller.

Green transportation: need, technology and challenges

Internal combustion (IC) engine based vehicles are the backbone of the modern transport sector. These vehicles use fossil fuels as a source of energy to propel it and emit toxic gases. These noxious gases harm the environment and causes human health problems. Hasty usage of fossil fuels results in rapid depletion of these resources and price inflation. These concerns encourage the modern society to discover alternatives for sustainable future transportation. Various fuel efficient technologies, like hybrid vehicles, are essentially the solution to fulfil the world’s need of greener environment. This paper discusses about various aspects like sources of pollution, decreasing level of fossil fuel, dependency on oil energy and need of green vehicles. It suggests to adopt hybrid vehicles, tells the challenges in accepting them as part of the transportation system and their remedies also. The status of hybrid vehicles on the roads worldwide and initiatives taken by different governments are discussed in lucent manner. The paper deliberately describes governments’ schemes to focus on securing its energy resources, trim down reliance on fossil fuels and to promote hybrid vehicles on roads in the pollution-free world.

Performance Analysis of Hybrid Electric Vehicle over Different Driving Cycles

Article aims to find the nature and response of a hybrid vehicle on various standard driving cycles. Road profile parameters play an important role in determining the fuel efficiency. Typical parameters of road profile can be reduced to a useful smaller set using principal component analysis and independent component analysis. Resultant data set obtained after size reduction may result in more appropriate and important parameter cluster. With reduced parameter set fuel economies over various driving cycles, are ranked using TOPSIS and VIKOR multi-criteria decision making methods. The ranking trend is then compared with the fuel economies achieved after driving the vehicle over respective roads. Control strategy responsible for power split is optimized using genetic algorithm. 1RC battery model and modified SOC estimation method are considered for the simulation and improved results compared with the default are obtained.

Energy management in hybrid electric vehicles using particle swarm optimization method

Increasing level of environmental pollution, petroleum prices and depleting level of natural resources are major troubles caused by internal combustion engine based transportation system. Hybrid electric vehicles (HEVs) have presented the solution to these problems and are assumed to be future green and sustainable transport medium. HEVs utilizes engine and battery together to give power to the wheels. Since, presence of two sources causes the complexity at architectural level of vehicle, hence requires a judicious power split between them. To split power efficiently between engine and battery, an intelligent energy management scheme is required to be implemented. An efficient power split scheme may consequence in better fuel economy and performance of HEVs. Here, particle swarm optimization based intelligent energy management scheme is implemented and compared with genetic algorithm and dividing rectangle algorithms. Modified state of charge (SOC) estimation method and 1RC battery model are used for simulation purposes in advanced vehicle simulator (ADVISOR).

Green transportation in India: Need analysis and solution

Modern transport sector heavily relies on internal combustion (IC) engine based vehicles and depends on fossil fuels as a source of energy to propel the vehicles. These vehicles add on environmental and human health issues due to the emitted toxic gases. Apace usage of fossil fuels results in rapid depletion of these resources and price inflammation; it stimulates to find alternatives in transportation technology. This brings out an innovative solution in terms of hybrid vehicle technology to fulfill worlds need for a greener environment. This paper discusses various aspects such as sources of pollution, decreasing level of fossil fuels, dependence on oil energy and need of green vehicles in context to India. Need analysis of hybrid vehicle technology makes it possible to determine Indias energy policies to focus on securing its energy resources. Also, it includes the challenges in adopting green vehicles, their remedies and Indian government initiatives to promote them on road.