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Viewing 181 to 210 of 22007
2015-08-20
Technical Paper
2015-28-0016
Srinivas Gulur, Arun Karuppaswamy Balasubramanian, Vinod John
Design of a suitable thermal model inclusive of the enclosure or cabinet, is an integral part of power electronic thermal management. This stems from the fact that power losses in an inverter may cause severe temperature rise in the enclosed cabinet, causing damage to the inverter. The work presents a thermal enclosure model for 3φ, back to back inverter topology rated 24 kVA which is kept in an enclosure having dimensions 1.524 ∗ 1.066 ∗ 1.828 cubic metre. Effects of the inclusion of the thermal enclosure model with the inverter thermal model have been investigated for the above mentioned inverter topology.
2015-08-20
Technical Paper
2015-28-0018
Abhijit Kulkarni, Vinod John
Inverters with high voltage conversion ratio are used in systems with sources such as batteries, photovoltaic (PV) modules or fuel cells. Transformers are often used in such inverters to provide the required voltage conversion ratio and isolation. In this paper, a compact high-frequency (HF) transformer interfaced AC link inverter is discussed. A high performance synchronized modulation scheme is proposed for this inverter. This modulation addresses the issue of over-voltage spikes due to transformer leakage inductance and achieves better input dc voltage utilization. The problem of spurious turn-on in the HF inverter switches is also mitigated. The performance of the inverter is validated experimentally with the proposed modulation.
2015-08-20
Technical Paper
2015-28-0021
Amar Singh, Bhupesh Agrawal, Umesh Bisen, Jim Shoemaker, Grant Shane
As the significance of emission regulation and the need of energy efficiency are increasing the need of hybrid vehicles is going-up. The integral part of hybrid vehicle architecture is high power density IPM machines but thermal management is key design criteria of these motors. These motors can be either air or oil cooled based on the power rating and losses generated in machine at operating points. In oil cooled machines, achieving optimum oil flow rates in critical regions at different speeds of the rotor is a major challenge in designing an electric motor. As the rotor speeds reach high values to about 10,000rpm the oil flow prediction from different rotor shaft bores becomes increasingly difficult due to significant centrifugal effects at such speeds at these bores. This paper discusses in detail the analysis methodology to predict the oil flow behavior from two parallel circuits namely the rotor and the stator up to high speeds of rotor.
2015-08-20
Technical Paper
2015-28-0019
Nimesh Vamanan, Vinod John
Classical control and one cycle control are popular methods to generate gating signals for active device in pwm rectifiers. One cycle control has lower control complexity when compared to classical control. However, in one cycle controlled converters there is a phase lag between fundamental voltage and current, which increases when the converter is loaded. In this paper the reason for phase lag is identified and a novel method to compensate for the same is presented. Effects of grid frequency variation on the degree of compensation is studied. The viability of the proposed compensation is validated using simulation and experimental studies.
2015-08-20
Technical Paper
2015-28-0026
Shailendra Kumar Gupta, Rakesh Srivastava, Som Nath Mahendra
The paper has been written focusing on stand-alone renewable energy based generation. Dual stator permanent magnet synchronous generator has been taken as an alternative to self-exited induction generator for stand-alone projects. The paper discusses the construction details, operating principle and feasibility studies of a dual stator permanent magnet synchronous generator in stand-alone renewable energy generation. In wind power, fresh water or sewage water stream based power generation, the turbine is driven at variable speed causing either over voltage or under voltage. The paper utilizes the principle of induction regulation for voltage control. Such controllers for dual stator permanent magnet synchronous generator has not been proposed yet. Use of Induction regulator could make the renewable generation free of any electronic component(converters) making the system affordable in remote areas though permanent magnets have been used.
2015-08-20
Technical Paper
2015-28-0028
Amit Kumar Singh, C Upendra Reddy, Kashyap Kumar Prabhakar, Praveen Kumar
Induction motors are presently used in many electric vehicle applications. As a result, their control methods have received a lot of attention. One of the efficient method of induction motor control is the direct torque control (DTC). In this paper, a design method for direct torque control of induction motor has been developed. A Verilog hardware description language is used to implement the developed DTC model on Nexys 2 FPGA kit. Field programmable gate array (FPGA) has many coherent advantages such as fast response, reliable, flexible,robust against load variations and programmable architecture. The same algorithm is designed and simulated using Matlab/simulink tool to make comparison with the designed model on FPGA which shows reduction in flux and torque ripples. Also, the simulated results are validated experimentally.
2015-08-20
Technical Paper
2015-28-0024
Amit Kumar Singh, Praveen Kumar, C Upendra Reddy, Kashyap Prabhakar
This paper presents the development of a cosimulation platform of induction motor direct torque control drive. This paper provides advanced modeling and simulation tool for induction motor drive. The proposed simulation platform allows a coupled analysis that links finite element analysis (FEA) with the simplorer for the more realistics simulation, analysis and validation. With the help of finite element analysis method (FEM), a three phase induction motor is simulated to obtain the flux-linkage vs. current curve. Thereafter, the constant magnetizing inductance is replaced by the new inductance which is a function of current. The obtained improved model is configured in MATALB/Simulink. In this paper, comparision between the Matlab/simulink and Ansys Maxwell simplorer cosimulation is done based on the direct torque control (DTC) of induction motor.
2015-08-20
Technical Paper
2015-28-0027
Shashikiran HK, Bhupesh Agrawal, Jim Shoemaker
With high elevation in magnet prices in recent times, switched reluctance machine (SRM) are gaining importance, due to the simple and rugged construction, low cost, and ability to operate over a wide speed range at constant power. SR machine operates due to the variable reluctance in the air gap, hence displays a highly nonlinear inductance behavior. This makes it impossible to carry out predictions that are accurate with liner formulations. Consequently, it becomes necessary to use the finite element method (FEM), which can handle nonlinear magnetic properties in material and minute geometry and also transient currents. This paper will discuss the virtual modeling and verification procedure established for SR machine to confirm the dynamic drive characteristics including the losses in the machine, at different switch timing w.r.t. operating speed. Keywords: Switched reluctance machine (SRM), Dynamic drive characteristics
2015-08-20
Technical Paper
2015-28-0030
Kamalakannan Durairaju, Krishna Vasudevan, Varada Iyengar Narayanan, N S Ramanathan
Permanent magnet synchronous machines (PMSM) are being used in numerous applications. Some of requirements need a single machine to operate, below and above the rated speeds. As there is no direct field control method in a permanent magnet (PM) rotor, injection of negative direct axis current is done to implement a flux weakening, which in turn, helps to achieve speeds beyond the rated speed. An alternative method for flux weakening is of great interest currently and different variable flux permanent magnet (VFPM) configurations have been studied. A new method of VFPM arrangement is proposed in this paper. Further, the design of components associated with VFPM assembly is also discussed. The performance comparison of conventional PMSM and VFPM is carried out. With the help of variable flux arrangement, operating speed of machine is extended to 2600 rpm from 1100 rpm. Further very good improvement in power factor and efficiency is observed in variable flux arrangement.
2015-08-20
Technical Paper
2015-28-0029
Makarand M. Kane, Naga Chaithanya, Kishor Bodnapu
With the advent of NEMMP (National Electric Mobility Mission Plan), increase in both production and demand of hybrid and electric vehicles is expected in coming years. Mild hybrid vehicles (MHV) are sought as one of the most plausible options among alternative-fuel-vehicles. There are two prime goals behind development of MHV – a) increase in fuel efficiency b) maintaining overall low cost of vehicle. The present work has considered a vehicle in small car segment as pilot vehicle. In the pilot-vehicle, electric power is used for threefold applications – a) eliminating idling energy losses with regenerative braking b) engine cranking and c) assisting engine during peak power demand. Thus, this application poses special requirements of starting torque and peak power – the starting torque being as high as 4 times the rated torque and extended range of peak power region.
2015-08-20
Technical Paper
2015-28-0033
Arindam Das, Anirban Konwar, Ankit Dalal, Praveen Kumar
Permanent magnet synchronous motors (PMSM) are increasingly being used for electrical vehicle application due to their high torque density. Performance of interior magnet PMSM motor depends on the magnet shape and the flux guides in the rotor. Rotor surface profiling affects the reluctance in the machines thus changes the direct (Ld) and quadrature (Lq) axes inductances of the motor. Effects of different magnet configuration, rotor surface profiling and variations in flux guides on important performance parameters like output torque, torque ripple and cogging torque have been investigated in this paper. PMSM motor used in Toyota Prius 2004 has been used as standard motor. Total magnet volume in the motor has been kept constant to ensure that the change in the performance of the motor is only due to the factors under investigation. Change in direct and quadrature axes inductances with the change in rotor configurations are also reported in the paper.
2015-08-20
Technical Paper
2015-28-0031
Kamalakannan Durairaju, Krishna Vasudevan, Varada Iyengar Narayanan, N S Ramanathan
The proposed concept in this paper is about how to achieve flux control at higher speeds in automotive alternators with PM rotors. The use of high energy magnet (NdFeB) in the rotor helps to achieve high power density and high efficiency in the alternator. The PM flux control at high speed is done by implementing a mechanical flux weakening arrangement which uses a simple worm wheel and DC motor to perform this phenomenon of flux control. The open circuit performance of standard claw pole alternator for different field currents at various speeds has been predicted. The components of the mechanical arrangement which has been used for achieving rotation have been discussed. Further, a suitable variable flux permanent magnet machine (VFPM) is designed with the same dimensions as that of the standard claw pole machine. The open circuit performance of VFPM is predicted and is compared with the conventional machine.
2015-08-20
Technical Paper
2015-28-0038
V S S Naga Karthik Tunuguntla, Kannan Subramanian, Kumar Prasad Telikepalli, Aravapalli Sriniwas, Ganesh Kumar Ramakrishnan
Designing a new product with a novelty involved in it, is called Product Design. This new product has to be sold by an Original Equipment Manufacturer to its customers. Development of this novel product design (Product Development Process) should be efficient & exhibit reliable operation across its lifetime fulfilling its customer expectations. Design for Six Sigma (DFSS) helps in achieving the same by a structured approach for product or process design. This paper demonstrates the DFSS (DMADV) implementation for the design of Thermal architecture to a xEV's energy storage system with unique& appropriate tools for analysis in each phase.
2015-08-20
Technical Paper
2015-28-0035
Mukund Kulkarni, Saravanan Meenatchi Sundaram, Vinten Diwakar
There is currently a trend in the automotive industry to replace combustion engines with electric motors or a combination of an electric motor and a combustion engine, thereby substantially reducing the environmental impact of automobiles by reducing or completely eliminating car emissions. In this paper various strategies for positioning of smoke sensor within the battery pack assembly for smoke detection are deliberated. Proper placement of the smoke sensor results in two important design objectives: to detect smoke as soon as the fire ignition and to achieve full coverage by using a minimum number of sensors. The challenge lied in designing and development of a suitable smoke sensor which meets stringent vehicular dynamic applications such as varying ambient operating temperatures, humidity, vibrations, mechanical shock, dust, etc. As the active fire protection is getting more and more important for electric vehicles in general and more so in battery pack assembly.
2015-08-20
Technical Paper
2015-28-0042
Sathiyaraj Asaithambi, Amitabh Vaidya, Jithesh VC
Battery is the primary and only source of power in the electric vehicle. Electric vehicle batteries differ from normal starting, lighting, and ignition batteries because they are designed to give power over sustained periods of time. Traction batteries are designed with a high ampere-hour capacity. Batteries for electric vehicles are characterized by their relatively high power-to-weight ratio, energy to weight ratio and energy density. These batteries facilitate the noiseless, pollution free and economical operation of electric vehicles. But this can be dangerous under some conditions and can pose a safety hazard if punctured or charged improperly since they contain a flammable electrolyte and are also kept pressurized. The development of safe, high voltage batteries is regarded as a major challenge. Thus in these batteries the gases are retained within the battery as long as the pressure remains within safe levels.
2015-08-20
Technical Paper
2015-28-0041
Rajasekhar MV, Parandhamaiah Gorre
Unlike fuel tanks as energy sources, high voltage batteries acts as energy sources for hybrid electric vehicles. These traction batteries have to operate under varied environments and provide energy to electric power train for vehicle propulsion. With the demand for production intent hybrid electric vehicles, the battery pack development for series production has been one of the focus areas in recent times. This paper details a systematic approach on the steps to be followed while developing a battery pack considering the vehicle requirements. These parameters include pack structural design, thermal management, cell protection, battery control monitoring, charging and testing parameters which needs to be considered for effective battery pack development.
2015-08-20
Technical Paper
2015-28-0044
Saravanan Meenatchi Sundaram, Mukund Kulkarni, Vinten Diwakar
Electric vehicles (EVs) are expected to play an important role in sustainable mobility thanks to the efficient energy utilization and zero–emission when in use. The battery has a great impact on the performance of electric vehicles, basically determining the driving range. As a consequence, the choice of the battery technology and its effective utilization is of paramount importance. Li-ion chemistry is very sensitive to overcharge and deep discharge, which may damage the battery, shortening its lifetime, and even causing hazardous situations. This requires the adoption of a proper Battery Management System (BMS) to maintain each cell of the battery within its safe and reliable operating range. In addition to the primary function of battery protection, a BMS should estimate the battery status in order to predict the actual amount of energy that can still be delivered to the load.
2015-08-20
Technical Paper
2015-28-0043
ChiruVenkat Reddy, Vikrant Singh, Rashed Rabaa
At low temperatures, the internal resistance of a Li-ion cell is very sensitive to its temperature and SOC. As such, conventional equivalent circuit based models often fail to predict the power obtainable from a cell under low ambient temperature conditions. Electrochemistry based models have shown good promise to model cell dynamics at low temperatures (subzero temperatures). In the current study, we use a previously developed electrochemistry based cell model, and couple it with electrical solver to carry out electro–thermal simulations. Full module level simulations with cell and associated electrical circuitry are carried out and cranking power (in short duration ~ 10-15 sec) deliverable from module estimated.
2015-08-20
Technical Paper
2015-28-0048
Sumit Gupta, Mohammad Khan, Tapan Sahoo
This paper deals in methodology creation of HEV plant model using Matlab-Simulink for testing the HCU (Hybrid control Unit) logics in dSpace Hardware-in-loop environment. Hybrid Controller requires certain inputs, which further process it and gives output. Inputs are provided in close loop environment by modeling all the Engine and Vehicle signals like Vehicle Speed, Engine Speed, Accpedal, Brake, clutch, Boost pressure, Rail Pressure, Motor torque, Battery SOC etc in plant model. Transfer functions are defined in plant model to convert the physical signals into digital, Analog and PWM signals for actual controller input. The model is able to test the Hybrid functions like stop start, recuperation, torque assist etc.Also it is used for vehicle performance and FE simulations with better accuracy as compared to conventional simulation.
2015-08-20
Technical Paper
2015-28-0049
Tariq Muneer, Mohan L. Kolhe, SK Adhikari, Ian Smith
All over the world, transport sector is contributing heavily towards Greenhouse Gas (GHG) emissions. The electric vehicles offers an elegant solution in terms of increasing overall efficiency compared with its fossil-fuel counterpart. Furthermore, if electric vehicles are charged with renewable electricity then GHG reduction is very significant. One of the main draw-back of the electric vehicle though is the sourcing of energy for air-conditioning of its cabin space. In this work, a fully-instrumented Renault Zoe electric car has been used to conduct experiments for parasitic energy consumption. The object has been to evaluate the proportion of the total energy consumption that is used for cabin ventilation. These experiments have been part of a wider project under which Edinburgh Napier University’s Transport Research Institute has operated a fleet of 18 electric vehicles over a two-year period.
2015-08-20
Technical Paper
2015-28-0046
Nabal Kishore Pandey, Satish Thimmalapura, Paul Isac
Clean and Green car is the new buzz word in automotive industry. Every major OEM in world today is working towards development of alternative propulsion technology due to current and upcoming stringent emission norms. Customer focus is also shifting towards improved fuel economy and environment. The encouraging fact is the development activity which once was predominantly concentrated in matured markets, has now attracted emerging markets also. Initiative in emerging markets towards development of Electric Vehicle and Hybrid Electric Vehicle has multitude of challenges arising from adapting products/ technologies to local conditions which are different from the prevailing conditions in matured markets. Customer Acceptance, Driving Behavior, Challenging Thermal Profile etc. needs to be addressed for the intended market to ensure viability and sustainability of the technology.
2015-08-20
Technical Paper
2015-28-0047
Sudha Bansal
This paper presents the small signal analysis and controller design of Dual Inductor Current-Fed Bidirectional Converter for Fuel Cell Vehicle. The proposed converter achieves soft switching of all switches in both sides and switching sequence for secondary side switches naturally clamps the voltage across the primary switches. Thus no additional clamping circuit is needed. Hence this converter is having high power density, high efficiency and low device requirement. State space averaging technique is used to derive the small signal model. The controller is designed using two loop average current control. Bode plots in MATLAB are plotted to verify the stability of the complete system and the simulation results obtained using PSIM 9.0 are presented to verify the controller design and converter’s transient performance.
2015-08-20
Technical Paper
2015-28-0052
Aisling Doyle, Tariq Muneer, Ian Smith
It is becoming widely accepted that the electric vehicle (EV) has found its place in the automobile market as a solution to many topical issues that face governments and policy makers, industrial stakeholders and even individuals in terms of energetic, economic and environmental sustainability. However, issues still surround the reliability of this technology that has resulted in slow penetration of the EV into the market as a competent competitor. This paper will focus on the heating aspect of the EV. The conventional internal combustion vehicle (ICV) uses ‘waste’ heat from the engine to heat the vehicle. With a battery powered vehicle there is no heat produced to provide thermal comfort to the vehicle cabin and so this must be a consideration when looking at the range, longevity and overall performance of the EV.
2015-08-20
Technical Paper
2015-28-0053
Zhaohua Wang, Gangfeng Tan, Xiaomeng Shen, Yifan Ye, Quan Zhou, Xiaolong He, Xintong Wu
Regenerative braking used in hybrid electric vehicle can recover energy while braking, which can improve the driving distance of electric vehicle. As commercial vehicles trend to large tonnage, the power of vehicle retarding is greater than the power of vehicle driving. It is hard to ensure braking stability of the automotive only relying on regenerative braking and influence driving safety. This research combines regenerative brake and eddy current retarder. It can extend retarding time by sharing the brake torque of eddy current retarder using the regenerative brake. Meanwhile the regenerative brake supplies electric power for eddy current retarder and it will improve the energy efficiency of system. This paper aimed at target type vehicle that is 20 ton new energy commercial vehicles, and established the regenerative brake model and eddy current retarder model, and then combined vehicle running conditions for the system simulation.
2015-08-20
Technical Paper
2015-28-0050
Shyam Kulkarni, Amitabh Vaidya, Priyanka Karwa
Electrical Safety is the most important factor considered while initiating circuit design for any EV modules. EVs contain very high battery power that can be devastating and extremely hazardous in case of any abnormalities. Hence Safety protection in the electrical circuits is the very critical and requires 100% accuracy. Electric vehicles contain many complicated circuitries. These circuits carry very high current & are operated at high DC Voltages. Thus in case of short circuit, very high current flows in the line that can cause severe damage to the car and also can be fatal. Hence each circuit is necessarily provided with protective elements like relays and fuses. Thus these fuses, which appear to be very small elements of the circuit, can become life saver in case of short circuits and can prevent huge damages. Hence, Proper selection of the fuses is very important and critical for an electric circuit. Generally fuses are selected by a very simple process.
2015-08-20
Technical Paper
2015-28-0051
Ankita Dwivedi, S K Singh, R K Srivastava
Hybrid Electric Vehicles driven by electric vehicles are very promising in reducing emissions by maintaining high efficiency. The presence of inverters for the electric vehicles adds additional cost and maintenance to the overall system. Line start PM motor is a very encouraging technique for hybrid electric vehicles without any need of inverters and requires very less space. Line start motor provides the advantage of line starting as an induction machine and running as synchronous motor. The paper deals with the analysis and development of a new type of line start permanent magnet (LSPM) machine with conducting sleeve and surface mounted magnets. The use of conducting sleeve for starting the machine as an induction motor and surface mounted magnets on rotor make the construction of LSPM very simple. The cogging torque produced due to interaction of slot and PMs are reduced due to the presence of sleeve over the PMs.
2015-08-20
Technical Paper
2015-28-0058
A K Gupta, V Kartik, C P Ramanarayanan
Hybrid electric vehicles are widely seen as potential solutions to the problems of exhaust emissions, fuel consumption and technical challenges to increase vehicle functionality. The present paper focuses on the design, development and performance evaluation of a parallel hybrid electric vehicle based on the concept of a new hybrid transmission. A light pick up diesel vehicle is selected as a platform for hybridization because this category of vehicles consumes a lot of fuel. A prototype of the new transmission system comprised of a coupled planetary gear set, clutches and brakes is built. This transmission utilizes two planetary gear trains coupled for multispeed capability and, has the ability to operate two power sources and to control such power sources independently from one another. To demonstrate the practical applicability of the transmission and this hybrid configuration, one prototype vehicle is built integrating the new transmission system.
2015-08-20
Technical Paper
2015-28-0059
Rajasekhar MV
Recent focus on environment impacts and energy efficiency has been a key consideration for any vehicle manufacturer currently. These scenarios have led to the development of hybrid vehicle powertrains to acts as an immediate step towards improving fuel economy and reducing emissions. The hybridization of powertrain leads to an increase in overall cost of the vehicle on account of the anticipated benefits of improving vehicle efficiency. This cost factor plays a critical role in acceptance of technology in developing countries such as India to be a wide success. Under such situations the vehicle manufacturer has to devise a strategy for choosing the right technology (parallel hybrid, series hybrid, B-ISG etc) for the right segment of vehicle that can play a major role in making the vehicle a big success.
2015-08-20
Technical Paper
2015-28-0055
Jignesh Sindha, Basab Chakraborty, Debashish Chakravarty
The dynamic stability of a vehicle is of profound significance which has led three wheel vehicles to be used for only low speed application. Static Stability Factor (SSF) is a commonly used safety rating for vehicles. In this paper, stability of a three-wheeled vehicle with two wheels on the front axle (2F1R), a three-wheeled vehicle with two wheels on the rear axle (1F2R) and a standard four-wheeled vehicle are compared. A particularized formula for SSF of a three wheel vehicle is derived. Critical cornering conditions for lift-off are identified for both three wheeler configurations. Three wheelers with tilting wheel mechanism are seen as a potential solution for high speed stability. The mathematical model is derived for dynamic load transfer in case of tilting wheels. A comparison is carried out for cornering stability enhancements that can be achieved through tilting mechanism during critical cornering conditions.
2015-08-20
Technical Paper
2015-28-0057
Sumit Gupta, Prateek Patel, Harish Chandra, Mohammad Khan, Tapan Sahoo
In Hybrid vehicles the torque split and Gear Shift optimization strategy is generally cycle dependent and behaves significantly different in Real world driving conditions. This project helps us to optimize the torque split and gear shift points simultaneously for Real World and certification drive cycle for Hybrid Electric vehicle. Now the level of trade-off in optimization between certification and Real World conditions can be selected. The methodology evaluates Objective function at each and every operating point for Internal Combustion Engine (ICE) and electric motor-generator (E-machine) corresponding to all possible torque split and gear shift combinations at a particular instant and finally choose one combination with a least value of objective function (which is dependent on emission and fuel consumption, and is restricted under various constraints like drivability, component operational limits etc).
Viewing 181 to 210 of 22007

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