Estimation of health parameters in industrial gas turbines

1. A method for operating a gas turbine and determining a deviation value of a health parameter of at least one component of the gas turbine, the method comprising:

operating the gas turbine based on control parameters calculated by a control unit, wherein the control parameters are calculated based on desired input values received from an input unit,

monitoring by the control unit a health of the component of the gas turbine by:

measuring with sensors a pressure value and a temperature value at a measuring point of the component,

determining a corrected pressure value based on a predetermined pressure correction factor of the component applied to the measured pressure value,

determining a corrected temperature value based on a predetermined temperature correction factor of the component applied to the measured temperature value,

determining an estimated actual value of the health parameter of the at least one component at least based on the corrected pressure value and the corrected temperature value,

providing a nominal value of the health parameter of the at least one component which is predicted based on at least one predetermined input parameter,

determining a deviation value by comparing the estimated actual value of the health parameter and the nominal value of the health parameter, and

conducting diagnostic analysis and prognostic analysis based on the deviation value to estimate a dynamic behavior of gas turbine health under steady state and transient operating conditions for operation of the gas turbine.

2. The method according to claim 1 ,

wherein the health parameter is indicative of a condition or health of a component,

wherein the nominal value of the health parameter is determined by a real time model of the gas turbine or laboratory tests of the gas turbine, such that the nominal value represents a theoretical value based on a new and/or clean gas turbine.

3. The method according to claim 1 , further comprising

determining the predetermined pressure correction factor by determining a ratio between an upstream pressure value at an upstream station located upstream of the measuring point of the component and a downstream pressure value at a downstream station located downstream of the measuring point of the component.

4. The method according to claim 1 , further comprising

determining the predetermined temperature correction factor by determining a ratio between an upstream temperature value at an upstream station located upstream of the measuring point of the component and a downstream temperature value at a downstream station located downstream of the measuring point of the component.

5. The method according to claim 1 ,

wherein the health parameter is indicative of a condition or health of a component,

wherein the health parameter is an efficiency parameter, and the deviation value is an efficiency deviation value, and/or

wherein the health parameter is a capacity parameter, and the deviation value is a capacity deviation value.

6. The method according to claim 5 , further comprising

measuring a shaft speed of a rotating shaft of the component, and

using the shaft speed in addition to the pressure value and temperature value in determining the capacity deviation value.

7. The method according to claim 5 , further comprising

comparing the capacity deviation value of the capacity parameter with a further capacity deviation value of the capacity parameter determined in a foregoing determination step for determining a variation of the capacity deviation value over time.

8. The method according to claim 5 , further comprising

comparing the efficiency deviation value of the efficiency parameter with a further efficiency deviation value of the efficiency parameter determined in a foregoing determination step for determining a variation of the efficiency deviation value over time.

9. The method according to claim 1 , further comprising

measuring a further pressure value and a further temperature value at a further measuring point of a further component,

determining a further corrected pressure value based on a further predetermined pressure correction factor of the further component,

determining a further corrected temperature value based on a further predetermined temperature correction factor of the further component,

determining a further estimated actual value of the health parameter of the further component based on the further corrected pressure value and the further corrected temperature value, and a further measured shaft speed,

providing a further nominal value of the health parameter of the further component which is predicted based on at least one further predetermined input parameter,

determining a further deviation value by comparing the further estimated actual value and the further nominal value.

10. A control system for a gas turbine, comprising:

an input unit,

a control unit,

wherein the control system is adapted to execute the method according to claim 1 .