Utilizing Simulation Tools to Ensure Successful Motor Start-up of Centrifugal Compressors in Ethylene Cracker Applications after Switch from Turbine to Electric Drive

Traditionally, critical compression processes in Ethylene plants have been steam driven due in large part to the high power demand of these units. However, current industry and global trends to curtail emissions and increase efficiency have highlighted the benefits, in this regard, of electrification (or motorization) of these critical processes. These potential changes result in a very different set of requirements and constraints in order to start and operate the compressor trains. To ensure that the motor is sized properly for the process conditions and operational expectations of the end user, simulation tools can be utilized to evaluate the torque requirements for various electrical configurations including direct-on-line (DOL), variable frequency drive (VFD), or soft-start current limiting devices. This paper will explore the system details relevant to developing a Speed vs. Torque curve, the sensitivity of the output to these variables, and the operational adaptations that may be required to support an electrification initiative.