An advanced alternating current electric drive system, discussed in this paper, is being developed by the General Electric Company for the Ford Motor Company. The integrated transaxle consists of an oil-cooled 50 hp ac induction motor mounted within a 2-speed transaxle. Direct current from the nominal 204 V battery pack is converted to variable frequency, variable voltage 3-phase ac current by a liquid-cooled transistor inverter. A custom-designed inverter motor controller, containing two 8751 microcomputers plus analog and digital circuitry, translates torque commands from the vehicle microcomputer-based controller to the inverter transistor base drivers that turn on/off power Darlington transistors darlington transistors at appropriate times. After a review of the electric drive system ratings, details of the transistor inverter will be presented. Control strategy and controller design will be summarized. Electric drive integration and system test results will be presented.
Samenvatting