Method for estimating drive torque of variable displacement compressor and system for controlling drive source rotation speed

摘要

The value of an estimated drive torque is prevented from greatly differing from an actual drive torque of a variable displacement compressor immediately after a refrigerating cycle is started. A first estimated drive torque that is calculated based on a physical quantity other than the pressure of a refrigerant and increases with lapse of time after the variable displacement compressor begins to compress the refrigerant and a second estimated drive torque calculated using the pressure of the refrigerant are compared and the one with the value closer to the actual drive torque is employed as an estimated drive torque of the variable displacement compressor.