Variable Speed Compressor, HFC-134a Based Air Conditioning System for Electric Vehicles

The vast majority of cars and small trucks are sold with factory installed air conditioning (approximately 80% in 1989). For electric vehicles to succeed in the marketplace, air conditioning will need to be offered as optional equipment, along with adequate heating and defrosting systems. While providing the level of cooling performance expected by vehicle operators, it is important that the power consumption of the air conditioning systems used in electric vehicles be minimized, to minimize penalties to vehicle range and performance. Due to the ongoing CFC-12 phase-out, air conditioning systems intended for EV applications beyond the early 1990's must use an environmentally acceptable alternative refrigerant.

This paper summarizes the design of a variable speed Scroll compressor based prototype air conditioning system for an electrically powered mini-van. The system refrigerant is HFC-134a and high performance heat transfer components are utilized. The selected lubricant and special construction materials are discussed.