Compressor system and method of controlling the same

1. A compressor system comprising:

a first compressor comprising:

an inlet at which a first inlet guide vane is provided; and

an outlet pressure sensor unit configured to measure a pressure at an outlet of the first compressor;

a second compressor comprising an inlet at which a second inlet guide vane is provided;

a third compressor comprising an inlet at which a third inlet guide vane is provided;

a first control unit configured to adjust a degree of opening of the first inlet guide vane based on the pressure measured by the outlet pressure sensor unit, configured to compare the outlet pressure of the first compressor with a set pressure to set the outlet pressure of the first compressor as the set pressure, and configured to generate a first signal including information about the degree of opening of the first inlet guide vane, the set pressure being less than the maximum operational pressure of the first compressor;

a second control unit configured to receive the first signal, and configured to send a second signal, corresponding to the first signal, to the second inlet guide vane and the third inlet guide vane so as to adjust a degree of opening of the second inlet guide vane to control an amount of fluid flowing into the second compressor and to adjust a degree of opening of the third inlet guide vane to control an amount of fluid flowing into the third compressor, respectively;

a first anti-surge valve unit connected to the first compressor and configured to adjust a point in time of surging of the first compressor or configured to reduce a number of occurrences of surging of the first compressor; and

a second anti-surge valve unit connected to the second compressor and configured to adjust a point in time of surging of the second compressor or configured to reduce a number of occurrences of surging of the second compressor,

a third anti-surge valve unit connected to the third compressor and configured to adjust a point in time of surging of the third compressor or configured to reduce a number of occurrences of surging of the third compressor,

wherein the second control unit is configured to adjust the degree of opening of the second inlet guide vane after the first control unit adjusts the degree of opening of the first inlet guide vane to set the outlet pressure of the first compressor as the set pressure,

wherein based on the pressure measured by the outlet pressure sensor unit, the first, second, and third inlet guide vanes and the first, second, and third anti-surge valve units are controlled,

wherein the degree of opening of the first inlet guide vane, the degree of opening of the second inlet guide vane, and the degree of opening of the third inlet guide vane are controlled to be equal, and

wherein, based on the outlet pressure of the first compressor, an opening degree of the first anti-surge valve unit, an opening degree of the second anti-surge valve unit, and an opening degree of the third anti-surge valve unit are controlled to be equal.

2. The compressor system of claim 1 , wherein the first control unit and the second control unit control the first inlet guide vane and the second inlet guide vane respectively so that the pressure at the outlet of the first compressor and a pressure at the outlet of the second compressor are equal.

3. The compressor system of claim 1 , further comprising a filter unit configured to receive the first signal from the first control unit, configured to remove noise from the first signal, and configured to transfer the first signal to the second control unit.

4. The compressor system of claim 1 , wherein the second compressor and the third compressor are connected in parallel with the first compressor.

5. The compressor system of claim 1 further comprising:

a first guide flow path connected to the outlet of the first compressor and configured to guide the fluid compressed by the first compressor to an exterior of the compressor system;

a second guide flow path connected to the outlet of the second compressor and configured to the fluid compressed by the second compressor to the exterior of the compressor system;

a third guide flow path connected to the first guide flow path and the second guide flow path and configured to guide the fluid to the exterior of the compressor system;

a vent flow path branched off from at least one selected from a group consisting of the first guide flow path and the second guide flow path and configured to guide the fluid to the outside; and

a surge valve unit provided on the vent flow path and configured to selectively open and close the vent flow path.

6. The compressor system of claim 1 , wherein the second compressor is provided in parallel with the first compressor.

7. A method of controlling a compressor system, the method comprising:

measuring an outlet pressure of a first compressor;

comparing the outlet pressure of the first compressor with a set pressure, the set pressure being less than the maximum operational pressure of the first compressor;

controlling a degree of opening of a first inlet guide vane and setting the outlet pressure of the first compressor as the set pressure;

converting information about the degree of opening of the first inlet guide vane into a first signal;

passing the first signal through a low pass filter, filtering the first signal to remove noise, and sending the filtered first signal to a second control unit;

sending, with the second control unit, a second signal corresponding to the first signal to a second inlet guide vane installed at an inlet of a second compressor and to a third inlet guide vane installed at an inlet of a third compressor;

setting a degree of opening of the second inlet guide vane to be equal to the degree of opening of a first inlet guide after the degree of opening of the first inlet guide vane is adjusted to be the set pressure;

providing a first anti-surge valve unit connected to the first compressor to adjust a point in time of surging of the first compressor or to reduce a number of occurrences of surging of the first compressor;

providing a second anti-surge valve unit connected to the second compressor to adjust a point in time of surging of the second compressor or to reduce a number of occurrences of surging of the second compressor;

providing a third anti-surge valve unit connected to the third compressor and configured to adjust a point in time of surging of the third compressor or configured to reduce a number of occurrences of surging of the third compressor; and

controlling the first, second, and third inlet guide vanes and the first, second, and third anti-surge valve units based on the measured outlet pressure of the first compressor,

wherein the degree of opening of the second inlet guide vane and a degree of opening of the third inlet guide vane is following the degree of opening of the first inlet guide vane to be equal.

8. The method of claim 7 further comprising setting the outlet pressure of the first compressor and a pressure at an outlet pressure of the second compressor to be equal.