Calculation of the Load of an Electric Drive of a Reciprocating Compressor of a Ship Refrigeration Unit

A four-piston marine refrigeration compressor is considered. The task is to find ways to improve the efficiency of the compressor driving motor by reducing energy consumption. A mathematical apparatus for determining the load torque of an electric drive of a compressor of a ship refrigeration unit has been developed. Using the parameters of the existing compressor, the value of the mechanical load on the shaft is determined, and a diagram of the moment of resistance of the electric drive shaft is plotted. The degree of torque pulsations on the shaft is estimated. It is determined that the compressor has large amplitude of torque pulsations on the shaft, which, in its turn, effects the value of the current pulsations in the electric drive. It is proposed to use the developed mathematical model describing the moment of resistance of the piston compressor shaft to determine the rational law of frequency or impulse regulation of electric drive parameters.