Can a Variable Speed Drive (VSD) compressor lower the operation cost or create higher costs in fields other than energy?
Reducing energy costs is becoming a top priority, so it's no wonder that VSD compressor units are increasing in popularity. There is a common belief that VSD compressors are the most efficient part-load rotary screw compressors. As much as I agree with the high quality of VSD compressors, I cannot stress more the importance of fine tuning and adjusting the compressor unit to the field working conditions.
For example, at full load, a VSD compressor increases power draw by 2%. The way to compensate for this loss is by using a permanent magnetic E-motor, which saves 4% of power.