Patent ID: 7472541

Claim:
A compressor control unit for controlling a compressor that supplies gas into a header tank, comprising: a pressure setter setting a pressure of said header tank; a pressure controller comparing a supply pressure measured value measured by a header tank pressure indicator that detects a pressure in said header tank with a supply pressure set value set by said pressure setter to thereby calculate a pressure manipulation value corresponding to a differential pressure as the result of the comparison; a compression condition corrector measuring a compression condition of the gas and making a correction, corresponding to a measured value as the result of the measurement, to increase or decrease a load command value inputted from outside to thereby calculate a corrected load command value; a command value function generator being inputted with the corrected load command value calculated by said compression condition corrector to thereby calculate a valve manipulation value; an opening command adder adding the pressure manipulation value as a correction manipulation value and the valve manipulation value calculated by said command value function generator to thereby calculate a valve manipulation correction value; a flow control function generator being inputted with the valve manipulation correction value calculated by said opening command adder to thereby calculate a flow control opening command value that increases with an increase of the valve manipulation correction value if the valve manipulation correction value is a predetermined value or more and put out this flow control opening command value as a manipulation signal into an inlet flow control means of said compressor; and a recycle valve function generator receiving the valve manipulation correction value calculated by said opening command adder to thereby calculate a recycle valve opening command value that decreases with the increase of the valve manipulation correction value if the valve manipulation correction value is less than the predetermined value and generate a control signal of a recycle valve located in a recycle line connecting between a suction side and a discharge side of said compressor.