摘要 |
The present invention is a compressor compressing air, an electric motor driving the compressor, and an inverter variably controlling a rotating speed of the electric motor, the compressed air manufacturing facility is provided with a pressure sensor detecting a discharge pressure of the compressor at an upstream side position of a discharge air system connected to a discharge side of the compressor, and a control apparatus computing a pressure loss of the discharge air system in correspondence to a rotating speed of the electric motor, and changing a control range of the discharge pressure of the compressor at the upstream side position of the discharge air system on the basis of the computation in such a manner that a terminal pressure at a downstream side position of the discharge air system comes to a predetermined range. |