초록 ▼

A method of preventing surge in a dynamic compressor is disclosed. The method includes providing an anti-surge valve having an adjustable opening for increasing the flow through a dynamic compressor. The next step is sensing process conditions in the dynamic control to determine a compressor load va

A method of preventing surge in a dynamic compressor is disclosed. The method includes providing an anti-surge valve having an adjustable opening for increasing the flow through a dynamic compressor. The next step is sensing process conditions in the dynamic control to determine a compressor load variable. A control system estimates a process disturbance model using the compressor load variable. The control system then adjusts a safety margin using a rate limited response and initiates a closed loop response using process feedback based on the process disturbance model. The control system adjusts the opening of the anti-surge valve according to the safety margin and closed loop response.

대표청구항 ▼

1. A method of preventing surge in a dynamic compressor, the method comprising the steps of: providing a surge valve having an adjustable opening for increasing a flow through the dynamic compressor;sensing process conditions in the dynamic compressor to determine a compressor load variable;estimati

1. A method of preventing surge in a dynamic compressor, the method comprising the steps of: providing a surge valve having an adjustable opening for increasing a flow through the dynamic compressor;sensing process conditions in the dynamic compressor to determine a compressor load variable;estimating a process disturbance model using the compressor load variable; andinitiating a closed loop control response to open the surge valve based on the process disturbance model wherein the closed loop control response is initiated by opening the surge valve as a function of a compressor dynamic operating point distance from a surge limit line wherein the surge valve is opened in a step response. 2. The method of claim 1 wherein the compressor load variable is determined based on a compressor driver power. 3. The method of claim 2 wherein a compressor driver is selected from the group consisting of a motor, steam turbine and gas turbine. 4. The method of claim 1 wherein the compressor load variable is based on compressor driver rotating speed. 5. The method of claim 1 wherein the compressor load variable is determined based on a system process variable. 6. The method of claim 5 wherein the system process variable is a header pressure or flow of a process associated with the compressor. 7. The method of claim 1 wherein the compressor load variable is determined based on mathematical modeling of a system component. 8. The method of claim 1 wherein the process disturbance model is estimated by using a digital derivative of the compressor load variable. 9. The method of claim 1 wherein the process disturbance model is estimated by using a delayed response of the compressor load variable. 10. The method of claim 1 wherein the process disturbance model is estimated by using a filter response of the compressor load variable. 11. The method of claim 1 wherein a surge model response of the compressor load is determined when a rate of change of the compressor load variable exceeds a defined limit. 12. The method of claim 11 wherein the compressor load variable is a flow of the compressor. 13. The method of claim 11 wherein the compressor load variable is a temperature measurement associated with the compressor. 14. The method of claim 11 wherein the compressor load variable is a pressure measurement associated with the compressor. 15. The method of claim 11 wherein the compressor load variable is a distance of the compressor operating point from the surge limit line. 16. The method of claim 11 wherein the compressor load variable is a power of a compressor driver. 17. The method of claim 11 wherein the compressor load variable is a speed of the compressor. 18. The method of claim 1 further comprising the step of differentiating a steady state response from process disturbance upsets. 19. The method of claim 1 wherein the step opening is a fixed rate of opening. 20. The method of claim 1 wherein the step opening is a varied rate of opening based upon the response of the process disturbance model. 21. The method of claim 1 wherein the surge valve is opened if a distance from the compressor dynamic operating point of the compressor to the surge limit line is at a distance less than a predetermined set point. 22. The method of claim 1 wherein the surge valve is closed using a rate limited response once a predetermined set point is exceeded. 23. The method of claim 22 wherein a rate of closure of the surge valve is adjusted based on the closed loop response. 24. The method of claim 22 wherein a rate of closure of the surge valve is adjusted based on the distance of the compressor dynamic operating point from the surge limit line. 25. The method of claim 1 wherein the compressor load variable is determined from at least two of a group consisting of the operating point as a function of the surge limit, power of a compressor driver, rotating speed of the compressor driver, and a system process variable. 26. A method of preventing surge in a dynamic compressor, the method comprising the steps of: providing a surge valve having an adjustable opening for increasing flow through the dynamic compressor;sensing process conditions in the dynamic compressor to determine a compressor load variable;estimating a process disturbance model using the compressor load variable; andinitiating a closed loop control response to open the surge valve based on the process disturbance mode wherein the closed loop control response is initiated by opening the surge valve as a function of a compressor dynamic operating point distance from a surge limit line wherein the surge valve is opened in a ramp response. 27. The method of claim 26 wherein the ramp rate of response is a fixed rate of opening. 28. The method of claim 26 wherein the ramp rate of response is a varied rate of opening based upon the response of the process disburbance model.