The degree of climate comfort afforded by today’s air conditioning systems is outstanding. Electric and hybrid vehicles present entirely new challenges for air conditioning technology, because A/C comfort can directly affect potential range. The series production of electric refrigerant compressors for these vehicle types requires an extended testing process. This program includes performance and durability testing under realistic conditions for development, as well as testing for quality management. To make this possible, IPETRONIK Environmental Testing, Hamburg-based IPETRONIK business unit, has developed a compact compressor test bench to comfortably run standard test cycles for electrically driven refrigerant compressors, as they are commonly used for mechanically driven refrigerant compressors.
compressor test bench features a very compact design that requires just three square meters of floor space for installation. It consists of a temperature-controlled, heat-insulated test cell for the compressor, a compressor drive unit with adjustable rotational speed for mechanical compressors, secondary brine circuits for the condenser and evaporator as well as supply devices. The test bench is configured for operation with environmentally friendly 1234yf refrigerant. Its control circuits and sensor technology include the following elements: condensation pressure and temperature, suction pressure and temperature, pressure and temperature at the expansion valve as well as at the crankcase (mechanical compressor), drive torque (mechanical compressor), ambient temperature for the compressor, superheat and subcooling, refrigerant mass flow, evaporator inlet pressure and much more.
The maximum capacity is 9 kW for the evaporator and 25 kW for the condenser. The temperature range for the compressor environment extends from +10 ° C to +120 ° C. The voltage on the compressor ranges from 120 V to 400 V. It is possible to test compressors with a refrigerant mass flow of up to 400 kg/h. Additional design features include a maximum compressor drive torque of 40 Nm and superheat control from 5 K to 45 K. The suction pressure ranges between 2 bar and 6 bar, and the condensation pressure between 12 bar and 25 bar. For electric compressors, communications are accomplished via LIN/CAN. Typical test applications include VDA, high/low temperature tests, Raffertests as well as FAT- and OEM-specific tests.
IPETRONIK Environmental Testing develops, builds and installs tailor-made test bed solutions for the simulation of all operational and environmental conditions. This business unit offers the complete spectrum of test beds and media supply modules for applications in the area of vehicle cooling (for coolant, charge air, and oil coolers, as well as for batteries, electric motors and exhaust gases). As a supplement to these offerings, IPETRONIK Environmental Testing also develops and supplies test beds for vehicle air conditioning such as system-, component- and calorimeter test benches. This covers applications for refrigerant condensers, evaporators, compressors und expansions valves. The test bed configurations comply with the requirements for the R134a refrigerant being used today as well as for the future alternatives, 1234yf and CO2 (R744).