Improving Range Robustness: Heat Pump Value for Plug-In Electric Vehicles 2017-01-1161

Integration of a new, complex technology which crosses powertrain system boundaries (and thereby involves multiple organizations), at the optimum cost-attribute balance, is a complex task. An example of such a technology is a Vapor-Compression Heat Pump (VCHP) system. A VCHP system uses a vapor-compression refrigeration cycle to ‘pump’ heat from ambient into the cabin. This system can be used to supplement or replace other less efficient heating systems (e.g. engine, LV-PTC air heater, HV-PTC coolant heater, etc.) - which will improve fuel economy. The use of a heat pump system impacts several primary attributes, including heating, cooling, fuel economy, and electric range. These attributes must be balanced in an ideal fashion against the substantial expense, if a VCHP is to be selected for use in a particular vehicle. This paper walks through the value equation for the VCHP from start to end, addressing potential concerns and opportunities. The paper demonstrates the ideally balanced system to use in a next generation battery electric vehicle (BEV). This includes consideration of a balance of cost, range, climate control, quality, and competitiveness, among other things.