This paper demonstrates the implementation of field-oriented control and rotor current estimation of an induction machine. A mathematical model was developed in Matlab/Simulink. A control system was implemented on a three-phase wound field induction motor to confirm the proposed method and estimated rotor currents. A dSPACE embedded real time controller is used to implement the control and experimental results have been obtained to confirm the proposed method.
In an attempt to convince people that battery-cars are high-efficiency vehicles, a project was conducted to demonstrate that dry-cell battery-powered vehicles can carry people and run at 100 km/h. Various types of resistance to run were reduced; the numbers of batteries on board, the shape of the vehicles, and the power-train were optimized; and the cars accomplished a top speed of 115.9 km/h at the Shirosato Test-course of the Japan Automobile Research Institute in Ibaraki-prefecture, on August 4, 2007. This paper describes the designs of the vehicles, and the motors and tires, in this research project.
Among transportation-related issues, the most effective measure for resolving the problem of oil resources is the electric car. The key to the practical use of electric cars is cell batteries, which are the source of power for such cars. From this point of view, we have conducted experiments to prove that a speed of 100 km/h can be achieved by using size-AA dry-cell batteries [JIS,2006], in order to promote the efficiency of electric cars among the general public. This paper describes the results obtained from studies conducted into the optimization of the battery-cell system, which is an important parameter for this project. In this study, Oxyride dry-cell batteries, developed by Matsushita Battery Industry Co., Ltd, were selected and used, since they are higher in output power and energy, and content than traditional alkaline dry-cells. The study results indicate that, when using these batteries in an area of large current discharge, safety and the highest efficiency are achieved when they are heated to 60°C. Based on these results, an optimal battery system using size-AA battery-cells was examined in order to achieve a speed of 100 km/h with a person on board a car, and the outcomes of this examination are described in this paper.
There has been an ever-increasing demand to increase the switching frequency, power density, efficiency and dynamic performance of switch-mode power converter, the development of soft-switching technology has taken an accelerated pace. This paper provides a review on the development of soft-switching power converters for electric vehicle (EV) propulsion and recent research trends will also be discussed, with emphasis on soft-switching converters for dc motor drives, soft-switching inverters for ac motor drives and soft-switching converters for switched reluctance motor (SRM) drives.
Acceleration and deceleration are the most important features in performance assessments concerning car's performance. Whether fuel consumption is good or bad has dominated the performance of cars in recent years, and thus many electric vehicles (EV) with high energy-efficiency have been developed. But problems relating to the running distance per charging, the charging time, and so on of electric vehicles have been preventing them from spreading more generally. Under this circumstance, we will analyze the acceleration and deceleration performances of cars and examine the most suitable method for using energy effectively. As to an EV, deriving the accelerated velocity, a, from a situation when electric input power, P, is given to an EV, driving at a velocity, v, is extremely important in order to find out the acceleration performance of a car. This paper analytically describes the results derived from the relationship between obtained the acceleration, a, and the input or regenerated power, P,. Also, this paper shows that the results obtained from the profile of the predicted velocity, v, based on the input electric-power, P, of accelerating cars, corresponds to the characteristics actually measured. It is pointed out here that the EV is very convenient to perform this analysis, because the value of the eclectic input power can be obtained easily by a current and the voltage to the motor on board. This method demonstrates possibilities for predicting the performance of electric vehicles.
Hawaii is an attractive proving ground for electric and hybrid vehicles (EHV) evaluation. Envisioning and embracing the needs for environmental-friendly advanced transportation technology developments, the Hawaii Center for Advanced Transportation Technologies (HCATT) and the Electrochemical Power Systems Laboratory (EPSL) at the Hawaii Natural Energy Institute (HNEI) of the University of Hawaii, are working together to promote and facilitate EHV development in Hawaii. This paper reports some of the recent activities in EHV evaluation, battery modeling, and fleet testing in the HCATT program. The fleet of EHV in this program includes battery-powered EV (BEV) and battery-fuel cell hybrid electric vehicles (HEV). We will present vehicle test results, battery modeling and simulation tool developments, and data analysis approaches that we developed and used in the program.
The ITE Battery Research group has developed a new organic battery activator for new and used lead-acid batteries. The chemical composition of the activators is a mixture of the soluble organic polymer such as polyvinyl alcohol and inorganic salts (metal ions). The detail morphological study are required for the formation of PbSO4 on the electrode. This paper summarizes the effects of the organic activator and metal ions in the activator during the charge and discharge. The chemical redox reactions were carried out for Pb and PbO2 powders with H2O2 in sulfuric acid. It is considered that these reactions give useful information for the electrode processes of lead-acid batteries. The experimental results support the basic concepts for life extension of lead-acid batteries by ITE activator.
This paper proposes the extend mileage of electric wheelchair using a hybrid system consisting of Ni-MH battery aided by fuel cell as its drive source. Driving power sources in the trial electric wheelchair using Ni-MH battery with a 24V, 6.7Ah and fuel cell with a 24V, 300W is aided by hydrogen storage material filled-up to capacity of 70NL with a pressure of 1MPa. At present, running characteristics of electric wheelchair using in-wheel brushless dc motor as the drive system measures the current and voltage supplied to it, and investigates the mileage when that is run at a specific speed. As a result, at a speed of about 4.3km/h, averaging values of generating current and voltage of hybrid system are 2.7A and 24V, respectively. Mileage of electric wheelchair using a hybrid system is improved to about 1.5 times comparing with Ni-MH battery only.
The Energy Storage System (herein after referred as ESS) consists of batteries and/or ultra-capacitors and BMS. Different type of EVs need different ESS. ESS is the key to the future of EV including PEV and HEV. The paper will present the current status and the future of ESS for PEV and HEV separately.
The plug-in hybrid vehicle has been taken as one of the main streams of electric vehicles world wide with the development of battery technology and the remaining obstacles by the fuel cell to be broken through. Fuel cell plug-in vehicle will follow the engine plug-in vehicle because of the more and more strict control of green house gas emission. At this moment, lithium battery is still expensive and safety problem remains. The performance of ultra capacitor has been significantly improved and the price goes down rapidly because of being used on harbor vehicle and mechanical facilities such like container/cargo cranes in-small-batch. It has become a popular ESS for energy regeneration such like the transit buses. The paper will present the advantage and the performance of a FC plug-in hybrid transit bus with ultracapacitors and NiMH batteries. The design and simulation will be covered in the paper.
This report describes the educational activities using electric vehicles in the past 10 years in the Kochi University of Technology, which was opened in 1997. Since the inauguration, extracurricular activities had been conducted in the intelligent mechanical engineering department in the university, and the author was a consultant for participated students. In this first report, the extracurricular activities using electric vehicles were the Eco-power race conducted in Kochi prefecture in 1997 and the Electric Vehicle Rallies in Shikoku Island in 1997-2000. Such activities were the first stage leaning for engineers to raise the motivation. Electric vehicles used in Shikoku Electric Vehicle Rally were converted ones from conventional automobiles. After such participation, the author switched the consultant role to an another faculty. In our laboratory the education has been conducted considering experiences in the real world as is described in the second report. One of the most promising experiences as mechanical engineers is a creation of thought to be design and production of products such as vehicles. Vehicles produced were small-sized hand-made electric vehicles, electric motorcycle, and tricycles. In this report, the former half regarding the extracurricular activities is described.
July 27, 2015 There had been a system trouble (from July 26‚ 2015 15:25 to July 27‚ 2015 1:00 (GMT)). The service has been back to normal.
July 15, 2015 A new online journal "Mechanical Engineering Letters" has been launched by The Japan Society of Mechanical Engineers (JSME). This publication of such a letter journal is not only a new experience but also a tremendous challenge for the mechanical engineering society.
May 01, 2015 Please note the "spoofing mail" that pretends to be J-STAGE.