Now-a-days, global warming, caused by the burning of fossil fuel, has been attributed to unusual weather conditions in the world and the melting of ice in the Arctic Ocean. In order to address this global challenge, there have been various activities in almost every society. Solar cells and fuel cells using clean energies are actively applied to the generation of electricity in homes and electric vehicles instead of using fossil fuel. Recently, solar generation systems, with a capacity of 30 kW have been installed in Huis Ten Bosch as an electric source for the theme park. However, teaching materials that are easy to understand regarding the use of clean energies are not generally used in elementary schools. Handicrafts and experiments using clean energies are especially required at an early time for schoolchildren from the viewpoint of ecology. This paper proposes a model of an amusement park in the near future operated by clean energies as teaching materials of elementary schools. Handicrafts using clean energies are a cable car operating on a fuel cell aided by a solar cell, a balloon tower and an electric train operated by a fuel cell.
When thinking about aviation and climate, researchers tend to focus on airborne operations. This aspect is obviously important, but the landside accessibility of an airport also results in climate impacting emissions. This paper analyses the current emissions balance originating from the passenger and employee transport to and from Brussels Airport. The CO2 emissions related to the different landside access modes are inventoried and in a second step suggestions are made towards potential improvements of the situation. The measures suggested in this paper consist of a transition towards hybrid and battery electric vehicles, a modal shift away from internal combustion engine vehicles and some specific political interventions. When combined, it is calculated that the suggested measures can save more than 30 % percent of the CO2 emissions originating from the landside mobility of Brussels airport.
This paper represents an alternative energy storage system in the drive line of a hybrid electric vehicle. The effect of the use of an EDLC (Electrical Double Layer Capacitors) as a power buffer to smooth rapid power fluctuations in and out of the batteries of a hybrid electric heavy truck is investigated. In this work a topology is presented where the performances of a battery pack in parallel with supercapacitors are evaluated in terms of stress and extending battery lifespan. According to this association the battery current drawn is reduced and the supercapacitor source supplies the majority of transient current and as a result the battery stress is reduced up to 30 %. Other laboratory tests showed a fourfold improvement over stand alone lead acid battery pack under a Dynamic Endurance Test in which the lifetime of the battery is increased with 30 %. This work has been carried out on computer simulations. Finally the simulations results are validated on a test bench.
Recent advances in Electric Power Steering technology have promised significant improvements in vehicle handling performance and safety. Electric power steering is a new kind of power steering which is developing rapidly these years due to their superior energy efficiency and energy conservation. This paper presents a possible design solution of an electric power steering actuator for hybrid electric vehicles. The design criteria of a tubular linear motor with interior permanent magnet are described and a tubular interior permanent magnet linear motor is designed and optimized with respect to weight and force ripple for Electric Power Steering application. Such an application requires low motor vibration and low force fluctuations which are considered in design process. A finite element analysis is used to validate the results obtained from the analytical model, comparing the magnetic field quantities as well as the mechanical force.
As one of the most attractive technologies for hybrid electric vehicles, the electronic-continuously variable transmission (E-CVT) propulsion system has received more and more attention. In this paper, a novel E-CVT propulsion system using coaxial magnetic gearing is proposed. It can achieve optimal fuel economy, minimum exhaust emission as well as good propulsion performance by flexibly distributing the power flows. Since the coaxial magnetic gearing can offer non-contact torque transmission, the drawbacks of low transmission efficiency, mechanical friction and audible noise aroused from the mechanical planetary gearing can be overcome. The connection topology and the operation modes of the proposed system are analyzed and discussed.
In this paper, the electronic-continuously variable transmission (E-CVT) propulsion system for full hybrid electric vehicles (HEVs) is reviewed. Firstly, the E-CVT propulsion systems are classified as two main groups, namely the gear E-CVT and the gearless E-CVT. Consequently, the development of E-CVT propulsion systems is discussed, with emphasis on their system architecture, principle of operation, merits and drawbacks. Finally, the development trend of E-CVT propulsion systems will be briefed.
The distribution of harmonics of an inverter output voltage in a PWM inverter can be improved by using a Random Pulse Width Modulation (RPWM) scheme. RPWM dose not affect the fundamental frequency component of voltage, however it can significantly reduce the acoustic noise and mechanical vibrations of an inverter-fed ac motor drive. Up to now, RPWM has been studied in many researches and various RPWM techniques have been introduced, but none of them have actually shown the effects of the behavior of the random signal on the frequency spectrum of the inverter output voltage and performance of the motor drive. In this paper, three different methods of random signals are employed. These different methods and the Probability Density Function (PDF) of the random signal generator will be studied and the performance of the drive is examined. Also a new method in utilizing random signal is proposed. In this method, the random signal is injected to reference value of the quadrature-axis current. It should be noted that the RPWM technique can not be utilized in hysterisis drives. Here, the random signal with different PDF is injected directly to quadrature axis current. The injection of random signal will directly affect the output responses. In this research, comparison between RSPWM technique and direct injection of random signal has been carried out. Different criteria such as total harmonic distortion (THD), torque ripple and frequency spectrum, efficiency and mechanical vibration have been analyzed. The indirect field oriented vector control drive is simulated by using Matlab-Simulink first, and the effects of various methods of employing random signal are compared and the best alternative is introduced. For the validation of the simulation results an experimental set-up is built. The experimental results confirm the simulation outputs. The simulation and experimental result show superiority of Direct Injection of Random Signal (DIRS) method in comparison with randomized Sinusoidal pulse width modulation (RSPWM) technique. Also it is realized that the DIRS method is very simple for implementation and does not need any extra hardware.
Predicting how the electric vehicle market will develop from now on is a very important issue for not only countries that have led the car market such as Japan but also for countries that are going to develop. Then, in order to predict the diffusion of electric vehicles, the diffusion speed and price transition of former cars was analyzed quantitatively, and research which clarifies the prediction method of the diffusion rate of a car was performed. The universal relation about the sale and diffusion of cars became clear by considering a technical element in it. Conventionally, the demand forecast of a new product was carried out after the sale start. Past experience and a specialist's opinion were adopted in part. In a prior study, it was shown clearly that there was great influence by the leading role of engineering development and production and sale of a key device in each product. The relationship means whether the process of technology development and production sales is initiated by the device manufacturer only or through collaboration with the product manufacturer. In this paper, the results could be extended to the auto industry and so the same tendency was observed. Furthermore, the results were applied to predicting diffusion and the price of an electric vehicle, and if the problems, which were the interference of the present diffusion, can be solved, the earliness of diffusion and transition of the price of an electric vehicle could be decided by the development speed of the battery. The problems were both the short mileage from one charge and the more expensive price in comparison a common vehicle. According to the result of consumer electronics apparatus, the case was that 20 % of diffusion will be carried out in about 5 years after sales start, and the prices at that time are 50 % or less compared with a start price.
Lunar rovers are required to traverse rough terrains with craters and sheer cliffs-often seen in locations of scientific importance. Recently, wheeled rovers have been gaining popularity in conducting planetary exploration missions. However, wheeled rovers are likely to get stuck in the soil while traversing such terrains. One way to solve this problem is to use flexible wheels. In this study, experiments were carried out to simulate actual running conditions using flexible wheels. The results showed that flexible wheels had a high level of performance when traversing loose soil on a slope. The experiments were carried out using various flexible wheels that allowed different amounts of deflection. The flexible wheels were made from beryllium copper, magnesium, and stainless steel. In these experiments, we measured slip ratio and sinkage for each of these materials.
The electric wheelchair controlled with a joystick has become an important form of transportation for severely disabled-people. The wheelchair can be operated easily at any speed and in any direction by tilting the joystick to certain angles and directions. But some accidents involving the joystick-type electric wheelchair may occur as, for example, unintended movements of the joystick are caused through involuntary movements by users with disabilities. Accordingly, some differences are found between how the joystick is operated and how the joystick actually moves; thus training is required for beginners among joystick users. Difficulty in using the joystick causes operational errors because the user feels stress caused by its operation while controlling the wheelchair. These types of accidents have been occurring intermittently. Aiming to solve such problems, research and development of an automatic-driving device has been conducted in order to secure safety in driving electric wheelchairs. But so far research has not been conducted into developing an operation-assist device. This type of device can be loaded onto an existing electric wheelchair as an additional device in order to prevent driving accidents, while keeping the additional cost very low. The device in this study was developed and was loaded onto an existing electric wheelchair so that the safety of users of existing electric wheelchairs can be easily assured while at the same time the cost is kept low. The number of electric wheelchairs has already amounted to about 100,000 in Japan. To achieve the aim, a method of measuring a distance by using ultrasonic waves is applied in order to develop a device which can automatically prevent the electric wheelchair from crashing into walls on the left and right sides of the wheelchair. Movements of the wheelchair in forward and back directions are controlled according to the driver's intention. Experiments conducted by using an electric wheelchair loaded with the newly designed device have verified that the wheelchair can drive safely while automatically detecting walls on the left and right sides of the wheelchair and other obstacles.
The running test of railcar was examined using large lithium ion battery in the local line in Japan. 90 kWh of Mn type lithium ion battery was used. The relation between running time and voltage, current and integrating watt was investigated in detail. The railcar was run when the lithium ion battery module was discharged between 660 V and 480 V. The use of lithium ion battery had little voltage changes and enabled the smooth running compared with contact-wire type railcar. On one charge, it was also found from the running test that the railcar could run for about 40 km and the mileage improved 9 %. The running performance of lithium ion battery type railcar was equivalent to the contact-wire type railcar. It was found that the railcar powered by lithium ion battery was effective for the replace of diesel type railcar in the local line.