ELECTRIC SYSTEM FOR ELECTRIC VEHICLE

摘要

PROBLEM TO BE SOLVED: To obtain the high energizing performance and cutting-off performance for a switch by employing a method for disconnecting a motor by opening the switch between an inverter and the motor when a malfunction occurs so as to open a main switch during the operation of a permanent magnet type synchronous motor at a high speed. SOLUTION: In the electric system for an electric vehicle drives a permanent magnet type synchronous motor as an AC motor for driving a permanent magnet type synchronous motor 5' via a voltage type inverter 4 with a battery as a power source, the system comprises a switch 90 having contacts 92, 93 for short-circuiting between the AC output side lines of the inverter 4. The contacts 92, 93 are normally 'opened' at the time of the normal operation of the system, and 'closed' when the DC input side of the inverter 4 is 'opened' during traveling of the vehicle, thereby short-circuiting the AC output side lines of the inverter 4 therebetween.