Hydro turbine with reduced cavitation

A method of operating a hydro turbine of a hydroelectric power plant, comprising:

• measuring, by using at least one motion sensor coupled to a rotor of the hydro turbine, motion of the rotor during operation of the hydro turbine and thereby generating acceleration data;
• acquiring, by at least one processor, the acceleration data for one or more operational parameters of the hydro turbine employed during said measuring, the one or more operational parameters indicative of power supply of the hydro turbine;
• computing, by the at least one processor on the basis of the acceleration data and the one or more operational parameters, at least one of a first derivative, a second derivative, and a higher derivative of the acceleration data and computing the at least one metric indicative of the effect of cavitation on the hydro turbine, on the basis of the at least one of the first derivative, second derivative, and higher derivative of the acceleration data;
• comparing, by the at least one processor, the at least one metric with at least one threshold and determining, on the basis of the comparison, whether the effect of the cavitation is too high;
• providing, on the basis of said determining, a control signal indicating unsuitability of the operation of the hydro turbine at the power corresponding to the one or more operational parameters;
• and
• changing, by an automated governing system of the hydro turbine on the basis of the control signal, at least one of the one or more operational parameters of the hydro turbine, whereby the effect of cavitation is reduced.

A system for reducing cavitation in a hydro turbine of a hydroelectric generation plant, comprising:

• at least one motion sensor configured to be coupled to a rotor of the hydro turbine, configured to measure motion of the rotor during operation of the hydro turbine and to generate acceleration data;
• a first interface configured to acquire the acceleration data and one or more operational parameters of the hydro turbine employed during said measuring, the one or more operational parameters indicative of power supply of the hydro turbine;
• processing circuitry configured to compute, on the basis of the measurement data and the operational parameters from the first interface, at least one of a first derivative, a second derivative, and a higher derivative of the acceleration data and compute the at least one metric indicative of an effect of the cavitation on the hydro turbine on the basis of the at least one of the first derivative, second derivative, and higher derivative of the acceleration data;
• a comparator configured to compare the at least one metric with at least one threshold and determine, on the basis of the comparison, that the effect of the cavitation is too high;
• a second interface configured to output, on the basis of said determination, a control signal indicating unsuitability of the one or more operational parameters;
• and
• a governing controller configured to change at least one operational parameter of the hydro turbine on the basis of the control signal whereby the effect of cavitation is reduced.

A system for reducing cavitation in a hydro turbine of a hydroelectric generation plant, comprising:

• at least one motion sensor configured to be coupled to a rotor of the hydro turbine, configured to measure motion of the rotor during operation of the hydro turbine and to generate measurement data;
• a first interface configured to acquire the measurement data for a plurality of different sets of one or more operational parameters and for a plurality of different power supply regions of the hydro turbine employed during said measuring, the one or more operational parameters indicative of power supply of the hydro turbine;
• processing circuitry configured to compute, on the basis of the measurement data for the plurality of different sets of the one or more operational parameters and for the plurality of different power supply regions from the first interface, at least one metric indicative of an effect of the cavitation on the hydro turbine;
• a comparator configured to compare the at least one metric with at least one threshold and determine, on the basis of the comparison, that the effect of the cavitation is too high;
• a second interface configured to output, on the basis of said determination, a control signal indicating unsuitability of the one or more operational parameters;
• and
• a governing controller configured to change at least one operational parameter of the hydro turbine on the basis of the control signal whereby the effect of cavitation is reduced.