What Is an Electric Drive System?

Electric drive systems use electric motors as opposed to combustion engines.

Electric cars refer to vehicles that run on electricity as opposed to gasoline. Their systems, called electric drive systems, take the place of internal combustion engines.

Electric Motors

Electric cars use electric motors as a source of propulsion. Electric motors convert electrical energy into mechanical energy via force generated by current carrying conductors. We measure electric motor power in kW (kilowatts). A 100 kilowatt-powered electric motor generates the equivalent of approximately 134 horsepower.

Motor Currents

Electric motors receive DC (direct current) power through an inverter device. The inverter converts the lower power DC current to higher power AC (alternating current.) Once converted, the AC power attaches to a three-phase AC motor. The three-phase system generates a magnetic field in the vehicle's electric motor, enabling a balanced, linear electrical load while reducing motor vibrations.

RESS

Electric drive systems often generate electricity via a RESS, or rechargeable electrical storage system. RESS systems can store electrical energy using a variety of methods. Static energy storage can take place in the vehicle through double-layer capacitors. The vehicle's flywheels can store kinetic energy, or on-board vehicle batteries can store chemical energy.

References

• "Electric Motors and Drives: Fundamentals, Types and Applications"; Austin Hughes; 2005

Resources

• "Fundamentals of Electric Drives"; Mohamed A. El-Sharkawi; 2000