Test Bench for Measuring the Energy Consumption of an Automotive Air Conditioning System 980291
Low energy consumption and passenger comfort in a car are two of the main requirements for automotive vehicle users. The energy consumption due to systems ensuring comfort, above all the air conditioning system (ACS), has to be studied to meet these needs at the same time.
Automotive ACS consumption is split between compressor mechanical power and air fan electric power. Those two series of power are measured for a wide range of operating conditions. Parameters influencing these powers are also analyzed.
The test bench is an insulated vehicle equipped with an air conditioning system. The engine has been removed to insert a refrigeration cycle instrumentation system, which records several parameters including temperatures, pressures and mass flow. The compressor is driven by a variable speed electrical motor. Compressor rotation speed, air temperature and flow at the exchanger inlets are controlled to reproduce a wide range of climatic conditions and various vehicle speed profiles.
The tests are run under various simulated climatic conditions.
The tests presented in this paper are based on an European regular vehicle speed cycle /1/. Results highlight those parameters which influence power levels, such as air temperatures and flows at the exchanger inlets, initial and setpoint temperatures in the compartment. Capacity is influenced by these parameters, but not necessarily as compressor power is.