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Mitsubishi Electric has developed a concept car “EMIRAI 2 xEV” that features an electric vehicle (EV) powertrain for safe, comfortable, eco-friendly driving experiences in the future. The vehicle was exhibited during the 2013 Tokyo Motor Show and the 2014 Automotive Engineering Exposition. The xEV is a four-wheel-drive EV with three motors: a water-cooled front motor and two air-cooled rear motors with integrated inverters. The rear wheels can be driven independently. The degrees of freedom of the actuation can realize improved maneuverability and safety. The vehicle is also equipped with an onboard charger with a built-in step down DC/DC converter, an EV control unit, a battery management unit, and electric power steering. All of the instruments are developed by Mitsubishi Electric. Motion control systems for the xEV have been developed based on our proprietary motor control technology.

Parking assist systems which relieve burden of drivers have been put into practice in the world. Mitsubishi Electric has also been developing several technologies to realize the system, where our products such as sonar (ultrasonic sensor), electric power steering (EPS), a motor, and an inverter are used. In the parking assist system, peripheral environment of the vehicle in a parking lot is detected with our sonar sensors and determine whether or not there is a parking space available. Estimation of the position and the attitude of the vehicle is also carried out. On the basis of the detection and the estimation, a smooth and efficient path to drive and park the vehicle is generated with an optimization technique. In particular, this paper focuses on a drive control for electrified vehicles to track the reference trajectory at a desired speed given from the assist system.

In recent years, the fuel consumption improvement of automobiles is indispensable due to the global move to reduce CO₂ emissions. Downsizing of engines by turbocharger obtains the output equal to a large engine, and improves the fuel consumption. However, turbocharger has the response delay called turbo lag. In order to improve a transient response, we developed a high-speed motor. The electric supercharger consists of high-speed motor and compressor, and drives compressor by high-speed motor instead of an exhaust gas turbine. By combining conventional turbocharger and electric supercharger, we developed two-stage turbocharger system. In this paper, we explained development of high-speed motor and inverter. And, as application example, we explained electric two-stage turbocharger system. The high-speed motor and inverter are connected without harness, and assembled in one single unit. The motor is driven at high efficiency by vector control.