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This paper describes the motor and inverter system developed for the Nissan LEAF that has been specifically designed as a mass-produced electric vehicle. The system produces maximum torque of 280 Nm and maximum power of 80 kW. The motor achieves a small size, high power, and high efficiency as a result of adopting the following in-house technologies. The magnetic circuit design was optimized for an interior magnet synchronous motor to attain the maximum performance figures noted here. The material technologies of the rotor and the stator facilitate high efficiency and the production technology achieves high density winding. The cooling mechanism is optimally designed for a mass-produced electric vehicle. The inverter incorporates the following original technologies and application-specific parts to obtain cost reductions combined with reliability improvements. The power module has an original structure with the power devices mounted directly on the busbars.

This paper describes a newly developed electrified powertrain that incorporates various energy-saving improvements and is intended for use on a 2013 model year EV. Based on a 2011 model year EV that was specifically designed and engineered as a mass-produced EV, this powertrain integrates the traction motor, inverter and charging unit to achieve a smaller, lighter package for expanding application to more vehicles. Integration of the motor and inverter in particular reduced the part count for enhanced assembly ease, in addition to reducing heat transfer, noise and vibration. The specific features described in the paper are the three points below. Improving the layout of the inverter parts in order to downsize and integrate the inverter with the motor. Reducing the transfer of heat from the motor to the inverter. Reducing the excitation forces of the motor and optimizing the inverter for noise and vibration.

A new series of 6 cylinder direct injection 8.4 liter diesel engines have been designed by Isuzu Motors Limited. Naturally aspirated, turbocharged and turbocharged-aftercooled versions, have been developed to meet the needs of 8 to 16 ton GVW commercial vehicles, as well as industrial and marine applications. These engines cover the range of 147 - 200 kw (195 - 270HP) output. The design objectives for these engines included such features as high output, better fuel economy, high reliability and durability, as well as minimum weight and cost. This paper deals with the design, development and performance aspects of these engines.

A single nano-spark back light photography method has been developed to record the image of non-evaporating diesel sprays injected into high pressure nitrogen gas. Relatively clear image of fine droplets and spray was obtained. An image analysis method has been developed to quantify the droplet characteristics which are in focus, such as droplet size and shape. Spatial and temporal distribution of droplets has been clarified. It was observed that the number of droplets around the nozzle tip region decreases by time, however a large number of droplets were observed at X=13∼25 mm from nozzle tip at t=300∼700 μs from injection start. Double-nano spark photography of diesel sprays was carried out and relatively clear double exposure images of droplets were obtained on the same film. Two dimensional size and velocity measurement of droplets were simultaneously carried out based on these photographs.

This paper presents the results of recent investigations carried out at Isuzu Motors Ltd. into the reduction of noise radiated from exhaust system of heavy duty diesel truck. Radiation noise from the exhaust system is considered to be originated from the following vibrations. One is the vibration transmitted from exhaust manifold and the other is the vibration excited by fluctuation of inside gas pressure. Each contribution to the noise is analysed in conjunction with experimental results. Also presented are the results of a study into the optimum way of isolating the vibration and the practical way of damping by using laser holographic interferometry technique.