CONTROLLING HVAC COMPRESSOR SPEED IN A VEHICLE

摘要

A heating, ventilation, and air-conditioning (HVAC) system in a hybrid or battery-electric vehicle is provided. The HVAC system includes a compressor that has its own dedicated motor to control its speed. The compressor includes an inlet pressure sensor to determine and output the suction pressure, and an outlet pressure sensor to determine and output the discharge pressure of the compressor. At least one controller can be programmed to determine the discharge-to-suction pressure ratio, and limit the operating speed of the compressor in response to the ratio exceeding a pressure-ratio-threshold. The pressure-ratio-threshold can vary based on ambient air temperature. In the event an inlet pressure sensor is not available, the operating speed of the compressor can be reduced in response to the outlet pressure exceeding an ambient-temperature-based variable threshold.

主权项

1. An HVAC system in a vehicle comprising:
a compressor; an inlet for providing refrigerant to the compressor; an outlet for discharging refrigerant from the compressor; and at least one controller programmed to limit operating speed of the compressor in response to a ratio of outlet pressure to inlet pressure exceeding a variable pressure-ratio-threshold.