Patent attributes
A refrigeration unit includes an evaporator circulating a flow of refrigerant therethrough to cool a flow of compartment air flowing over the evaporator, a compressor in fluid communication with the evaporator to compress the flow of refrigerant, an engine operably connected to the compressor to drive operation of the compressor, an expansion device in fluid communication with the flow of refrigerant, and a controller operably connected to at least the engine and the expansion device. The controller is configured to determine an available power to drive the compressor, determine a compressor discharge pressure upper limit based on the available power, compare the compressor discharge pressure upper limit to a requested compressor discharge pressure, and initiate adjustment of the expansion device such that an actual compressor discharge pressure is the lesser of the requested compressor discharge pressure or the compressor discharge pressure upper limit.
