International Journal of Electric and Hybrid Vehicles (14 papers in press)
Analysis of performance improvement in energy storage system for electric vehicles: a review
by V.M. Dileepan, J. Jayakumar
Abstract: The selection of the energy storage system is crucial for electric vehicles. It should have good energy density and considerable power density, and also it must be light weight. So a battery with considerably high energy density must be used in electric vehicles. Lithium ion batteries are very much preferred as electric vehicle batteries. They have high energy density, high life cycle and smooth operation. But the problem related to lithium batteries are they have high temperature sensitivity, and their operation will be affected by over-current charging and over-current discharging beyond their maximum rated values and also be influenced by driving conditions and performance of motors used. So a battery management, control and optimisation system is essential in electric vehicle battery packs. This paper is a review of the design of a novel battery management and control system for lithium ion batteries for performance improvement in electric vehicles.
Keywords: battery; battery management system; control of energy storage system; driving pattern; energy storage system optimisation; electric vehicles; lithium ion battery; motor selection for electric vehicles; performance improvement; vehicle range.
Electric vehicles in India: current trends and future forecasts
by Vishal Shukla
Abstract: As globalisation is increasing, so is the demand for oil-based energy which is ultimately resulting in the rapid fluctuation of the market prices of the crude oil due to the basic principle of economics Law of Demand. This volatility and uncertainty in crude oil's demand and prices create pressure on governments and policymakers to look at new alternatives, one of them being the adaptation of green technologies. Green alternatives seem to be the trend of the future business and markets. Many business giants are compelled to spend heavily on their R & D and come up with innovative technologies focusing mainly on green technologies. In line with the developed countries, India, as a developing economy, is all set to plunge into this new innovative market of Electric Vehicles (EVs) and aims to become a major producer of the EVs for the Indian market as well as the globally. So, this research article aims to explore the expected demand for EVs, the market share, and the contribution of the EVs and associated technologies to foreign trade.
Keywords: disruption; Electric Vehicle; Green Technology; Indian Economy; Innovation; Market Demand.
Research on equivalent fuel consumption minimisation strategy design and optimisation for a plug-in hybrid electric vehicle
by Huan Guo, Weishun Deng, Fan Yu
Abstract: In this paper, an Equivalent fuel Consumption Minimization Strategy (ECMS) based on the optimal fuel economy is proposed and optimised for the Charge Sustaining (CS) period of a Plug-in Hybrid Electric Vehicle (PHEV). To overcome the disadvantages of low convergence rate and insufficient of population evolution, the crossover probability and mutation probability of the Standard Genetic Algorithm (SGA) are improved to be varied along with the iteration and fitness value. Meanwhile, an elite retention strategy is adopted to avoid the population degradation. The fuel equivalent factor is then optimised by Improved Genetic Algorithm (IGA) to obtain the optimal fuel economy. Corresponding hardware-in-the-loop simulations are carried out to verify the effectiveness and rationality of the strategy optimised by IGA. The results indicate that within allowable deviation of the state of charge, the PHEV can obtain better fuel economy by combining the proposed method.
Keywords: plug-in hybrid electric vehicle; charge sustaining; energy management strategy; improved genetic algorithm; fuel economy.
Automatic discovery and selection of most qualified electric vehicle charging station
by Raziq Yaqub, Kaveh Heidary
Abstract: Media reports that Electric Vehicles (EVs) still outnumber public charging stations by more than six to one is consistent with the early stage of electric car deployment. Thus finding charging stations may be a daunting task for EV drivers. Though the issue can be dealt with by providing online directories, web-based charging station locators and GPS-assisted gears, these methods are not adequate, because they do not help EV drivers automatically discover and select the most qualified EV charging station. Thus it will be frustrating for a driver to reach a certain location, or multiple locations, and not find a service because of grid inadequacy, long waiting queue, neighborhood safety, or the value he was looking for. This paper introduces a method and apparatus based on which the smart client installed in an EV would automatically discover, shortlist, and select, or recommend to the EV driver, the most qualified EV charging station.
Keywords: electric vehicle charging stations; most qualified EV charging station
Charging station Discovery; Selection; and Status Server (CDSSS); CDSS Client (CDSSC).
Energetic macroscopic representation and inversion-based control of fuel cells in a series hybrid race vehicle system
by Zainab Asus, El-Hassane Aglzim, Daniela Chrenko, Luis Le Moyne
Abstract: This paper studies the replacement of the engine and generator as a range extender in a hybrid racing car with a fuel cell system. A model of the original system of the car using a range extender consisting of an internal combustion engine and electric generator has been developed respecting the action-reaction principle used by Energetic Macroscopic Representation (EMR) and its Inversion-Based Control (IBC) to organise its subsystems' interconnections according to the physical causality. Results from drive tests of the real car on racing circuit are used to validate the model. The objective of this paper is to study the parameterisation and the integration of the fuel cell stack components based on this model. A diagnosis on the applicability of a control strategy as well as the improvements that can be effected by implementing a fuel cell system can be obtained using this model.
Keywords: hybrid vehicle; fuel cell; control strategy; energetic macroscopic representation; modelling.
Research on high speed avoidance path tracking of pure electric vehicles
by Jian Wang, Jun Yang, Peng Yu
Abstract: High-speed avoidance assisted driving technology can improve the driving safety of automobiles and is one of the key technologies of autonomous automobiles. The sigmoid function with continuously changing curvature is introduced to design a high-speed avoidance path. Based on the two-degrees-of-freedom vehicle dynamics model, a linear sliding mode auto-disturbance rejection path tracking controller is designed to control the actual yaw rate of the vehicle to track the ideal yaw rate of the planned path. Based on CARSIM software, a front-drive pure electric vehicle is established, and the control effect is verified by CARSIM and SIMULINK joint simulation method. The simulation results show that the path tracking controller can ensure that the pure electric vehicle tracks the ideal planned path and that the vehicle avoids the vehicles in front safely at high speed.
Keywords: high-speed avoidance; pure electric vehicles; path tracking; joint simulation.
Drivetrain modelling and parameter calculation for an electric bus with fixed or two-speed gearbox
by Martin Novak, Jaroslav Novak, Josef Morkus, Lubomir Musalek, Oleg Sivkov
Abstract: This paper presents drivetrain calculations for an electric bus. Parameters such as motor parameters, gear parameters and motor efficiency map calculation are used. The goal of the calculation is to select the suitable motor and gearbox. Synthetic driving cycle SORT2 and real-life driving cycles measured on bus lines are used. Based on the bus manufacturer assignment, only Permanent Magnet Synchronous Machines (PMSM) are considered. The motor output power is considered in the range of 120-160 kW. Also the selection of axle gear ratios was limited to 6.19, 6.5 and 7.35, as those are readily available. The considered gearbox was either a fixed one, with gear ratio of 1.8, or a two-speed gearbox with a gear ratio of 1 and 1.8. The calculations have shown that a two-speed gearbox can decrease the energy consumption. However, the improvement over a fixed gearbox is only in the range of 1-3%, dependent on the motor option and driving cycle. For the given parameters, the two-speed gearbox does not improve the overall bus parameters since it increases the complexity, cost, size, and maintenance, and worsens the reliability.
Keywords: electric vehicles; motor drives; permanent magnet motors; torque control; variable speed drives.
Technical analysis for implementing BS-VI automotive emissions norms with respect to electric vehicle production by 2020 in India
by Devendra Vashist, Farhan Mukhtar
Abstract: Automotive pollutants include carbon monoxide (CO), nitrogen oxides (NOx), hydrocarbons (HC), particulate matter (PM, mostly soot) and oxides of sulphur (SOx). Government of India has decided to implement BS-VI norms by April 2020. Another direction in which the auto sector is likely to move is electric mobility. In this research, a comparative study in terms of financial and social-economic costs is made between challenges to be faced by the auto sector shifting toward electric mobility and making BS VI compliance vehicles. For the analysis, M&M e20 and Maruti Suzuki Alto 800 brand which are similar size and volume, but powered by two different sources, were chosen for the study. From the analysis, it is observed that shorter mileage, frequent battery recharging, frequent maintenance and less charging infrastructure are areas that have to be addressed by the auto industry for commercial viability. Lithium ion batteries are least suitable but research on sodium ion batteries is in initial stages in India. For BS VI compliance, the Lean Electronic Fuel Injection System (LEFIS) and Exhaust Gas Recirculation (EGR) have to be implemented. Based on the analysis, it is recommended that the industry should adopt a hybrid model before completely switching to electric mobility.
Keywords: electric vehicles; BS VI norms; emissions; lean electronic fuel injection system; exhaust gas recirculation.
Brake blending and torque vectoring of road electric vehicles: a flexible approach based on smart torque allocation
by Luca Pugi, Tommaso Favilli, Lorenzo Berzi, Edoardo Locorotondo, Marco Pierini
Abstract: Application of regenerative braking on electric vehicles has a large impact on several aspects of design, implemented functionalities and overall performances of road vehicles. In particular, multi-quadrant capabilities and improved control performances of modern electric drives can be fully exploited to improve vehicle efficiency, stability and overall environmental impact. Conventional, mechanical friction brakes are currently devoted not only to stop the vehicle but also to the actuation of safety related mechatronics systems such as electronic braking distribution (EBD), AntiBlockierSystem (ABS) and electronic stability control/program (ESC/ESP). The result is an over-actuated system of electrical (electric motors) and mechanical actuators (friction brakes), whose mixed, blended application has to be carefully optimised. In this work a simplified approach is proposed in which concepts transferred from previous studies on high speed trains and autonomous vehicles are re-purposed and adapted in an innovative way to electric road vehicles.
Keywords: vehicle dynamics; regenerative braking; mechatronics; optimal thrust; brake blending; torque allocation; brake wear; energy consumption; electric powertrain modelling; in-wheel motor.
Developed operation of inverter fed induction motor to drive the electric vehicle
by Basem E. Elnaghi, Hamed A. Ibrahim, Shereen A. Elsayed, Fathy Abd-Elkader
Abstract: This paper focuses on increasing the operating efficiency of the inverter drive induction motor for electric vehicles. The vehicle speed control is achieved by changing the frequency from 5 Hz to 100 Hz. In this work, characteristics of the inverter control induction motor drive are established. The mathematical analysis is developed by the computer programs. The computed characteristic curves are obtained. Due to the difficulty of obtaining an actual electric vehicle in the lap, a fan load equivalent to the electric vehicle is used. The load characteristics are measured at different applied voltages for energy saving.
Keywords: three phase induction motor; control induction motor; traction application; electric vehicle; inverter; power electronics; motor drive; Matlab; simulation; experimental induction motor.
Graphene: future of high power density electrical machines for electric vehicle applications
by Ramesh Pandiyarajan, Lenin Natesan Chokkalingam
Abstract: The key challenges faced by many of the industries in the present scenario is to develop a high power density electrical machine. The advancements in material technology help the industries to enhance the power density as well as the efficiency of an electrical machine to a greater extent. Conductors play a major role in improving the machine's performance. In this paper, the role of conducting materials in high power density electrical machines are discussed. Graphene is an advanced nanomaterial that exhibits excellent conductivities with low mass density. Using graphene coated windings, the weight and volume of the machine can be reduced significantly. In order to understand the prominent features of the nanomaterial based conductors, a case study has been carried out in different electric vehicles such as Toyota Prius (2017), Nissan LEAF and BMW i3. Moreover, a major constraint in high power density machine is the temperature rise, which is discussed at the end.
Keywords: electrical machine; graphene; high power density; conductor; electric vehicle.
A parameter matching study for power system of electric sweeping vehicle based on AVL CRUISE
by Jianwei Ma
Abstract: Electric sweeper is the hot spot of research and development at present, and parameter matching design of power transmission system is a key technology. The practical significance of developing electric sweeper is introduced, the parameters of power system are designed based on the energy transfer of the whole vehicle, parameters of the motor and power battery are designed and selected to meet the performance design target, and the final drive and the second gear ratio are determined. The whole vehicle model is established and dynamic analysis is carried out using AVL CRUISE software. The simulation results show that the parameters designed for the power system meet the design requirements. It provides a reference for the design and research of power system of electric sweeper.
Keywords: power system; parameter matching; AVL CRUISE; electric sweeper; parameter design; power battery parameter; driving system parameter; simulation model; shift control; two-parameter shift strategy; UDC work conditions; acceleration time; maximum climbing degree.
Increasing fuel economy of commercial transport by using a hybrid power train
by E.S. Meltsyn, A.A. Markina
Abstract: Undoubtedly, the issue of increasing the fuel economy of passenger commercial vehicles is one of the most important, since the annual increase in the cost of fuel leads to an increase in the fixed costs of not only transport companies, but also small and medium-sized businesses. Using a hybrid power train (HPT) can reduce fuel consumption in the urban cycle, which is important for commercial vehicles used to deliver goods and passengers within the city, especially when it comes to megacities where traffic is difficult and average speeds are not high. Unfortunately, the cost of cars with a HPT, such as Toyota Prius, Lexus RX 450H, Ford Fusion Hybrid and others, remains quite high and cannot be fully compensated just at the expense of fuel economy.
Keywords: hybrid electric vehicle; fuel consumption; fuel economy; mild hybrid.
Experimental study of lithium-ion battery cooling using mixture of phase change materials
by R. Pradeep, T. Venugopal
Abstract: Phase change materials (PCM) are of attractive interest in electricity storage and power management applications. In this paper, PCMs are used for thermal management of an electric battery pack. Paraffin with a melting temperature of 58°C, OM35 with melting temperature of 35°C, two PCMs (paraffin and OM 35) were used for the study, as mixtures at two different ratios (50 : 50 and 60 : 40). Computations and experiments were allotted to estimate the heat transfer, solidifying and melting characteristics of the PCM utilised in the Li-ion cell battery module. Since PCM has low thermal conduction, thermal improvement techniques were investigated by inserting the copper plate into the PCM mixtures to boost the thermal conduction. PCM combination 50 : 50 is capable of holding battery running temperature compared to PCM combination 60 : 40. PCM combination 50 : 50 evidences to be ideal and lowered the operating temperature of the battery pack to 47°C.
Keywords: Li-ion cell; battery thermal management; PCM; phase change materials; CFD; computational fluid dynamics; battery module; copper plate; PCM combinations.