The objective of a variable frequency drive within a screw compressor environment is to provide a cost effective solution for the customer with a varying air demand whilst maintaining a constant system pressure. The HPC SIGMA Frequency Control SFC) drive system is an evolution of the variable speed screw compressor revolution and represents the very latest advancement variable frequency drive technology.
In developing these screw compressors, particular consideration was given to avoiding any specially designed high speed drive motors and airends. Although these may reduce the initial purchase cost they can result in severe limitations on reliability, airend efficiency and component service life.
Developed and designed specifically to complement and enhance the range of HPC energy efficient rotary screw compressors, the unit combines SIEMENS AG drive technology with the unique HPC KAESER SIGMA profile airend and SIGMA Control system to provide outstanding performance characteristics. Large, low speed SIGMA profile airends deliver excellent performance over the whole of the controlled speed range ensuring unrivalled specific power ratings.
The efficiency of screw compressors that are speed controlled by a frequency inverter is not constant over their whole range of control and if variable speed compressors are wrongly used, they can turn into power eaters without the user being aware of this. The path to maximum energy efficiency is the correct application of screw compressor control systems. Applied in the correct circumstances and system configuration by Maziaks, the selection of an SFC variable frequency drive screw compressor can deliver significant additional energy and cost savings.