Automotive electrical system having a starter/generator induction machine

A motor vehicle electrical system for starting an internal combustion engine and generating electricity for charging a vehicle storage battery and energizing vehicle electrical loads, comprising in combination:

• an induction machine coupled to the engine for bi-directional rotary mechanical energy exchange;
• bi-directional bridge circuit means electrically coupling the storage battery and the induction machine for bi-directional electrical energy exchange;
• control means for controlling the operation of said bridge circuit means (1) in an engine starting mode to operate said bridge as an inverter for energizing said induction machine with substantially sinusoidal voltage derived from the storage battery, and (2) in a generating mode to operate said bridge as a converter for drawing energy from the induction machine for charging the storage battery;
• and
• load converter means coupled between the storage battery and the electrical loads for drawing current from said storage battery at a predefined load voltage for energizing said electrical loads.