ELECTRICAL SYSTEM OF ELECTRIC VEHICLE

摘要

PROBLEM TO BE SOLVED: To highly maintain vehicle operation performance and system efficiency by preventing the traction characteristics and the maximum operation speed of a vehicle from decreasing. SOLUTION: In an electrical system of an electric vehicle, the power of a DC power supply is supplied to an electric motor for driving wheels via a semiconductor power converter for driving wheels such as an inverter, the electric motor is driven at a variable speed, and the car is driven or an engine and the DC power supply are used together as a power source. A step-up/down chopper 200 is connected between a recharging device 1 as the above DC power supply and an inverter 2 and is controlled so that a DC input voltage of the inverter 2 or the like becomes nearly constant. The operation voltage of equipment such as the inverter 2 and the electric motor can be maintained nearly constantly, thus optimally designing the operation points and miniaturizing the equipment and reducing its weight and price.