Electric motor driving reciprocating compressor can cause large power pulsations in electric systems. As a result, it is necessary to oversize the protections (circuit breakers and fuses) and may require reactive compensation equipment to increase the voltage stability of the supply system. Reciprocating compressors are driven by both synchronous and asynchronous motors, but, due to their characteristics and peculiarities, synchronous motors are more widespread and studied compared to induction motors. In recent years, through extensive use of electric drives, induction motors are increasingly involved in the implementation of the compression trains. In a first time, the analysis of the compression train was made considering the induction motor as a simple inertia, such as the synchronous motor. Recently, the effects of the air-gap torque are considered in the induction motor model, allowing to simulate more accurately the entire system. In this paper, the transient power pulsation evaluation in reciprocating compressor train, based on air-gap torque effects of the electric motor, is presented. Because the analysis involves both electrical parts and mechanical parts, the multiphysics equations are derived, and the MATLAB/Simulink model is realized. Finally, to verify the proposed procedure, a real compressor train was simulated.