Method and apparatus for automatically index testing a kaplan turbine

Method of automatically determining, for a plurality of gross headwater levels and gate positions, optimal operating angles providing peak generating efficiency for variable pitch blades of a Kaplan-type turbine having movable gates, said turbine being controlled by a governor and an electronic 3D cam, said method comprising the steps of:

• running the turbine on-cam at, and using the governor to control the positions of said gates so as to maintain said turbine at, a predetermined setpoint power generation level;
• measuring nn-cam values of particular operating parameters of the turbine;
• evaluating the measured data to determine whether the turbine is operating in a steady-state condition;
• when steady-state operation has been achieved, comparing the measured on-cam data with data compiled in a memory of a microprocessor to identify unique on-cam operating points;
• upon identifying a unique on-cam operating point, making a series of incremental off-cam variations in the pitch of the blades of the turbine in both flatter blade angle and steeper blade angle directions;
• after making each incremental variation in the pitch of the blades, allowing the governor to reposition the gates so as to return the power generation level of the turbine to the setpoint, monitoring the operation of the turbine to determine when it has returned to steady-state and then measuring values of the particular operating parameters at the new gate-blade operating point;
• computing an efficiency value corresponding to each of the measured operating points;
• and
• comparing the efficiency values of the measured operating points to identify a peak value.

In a system for testing a hydro-powered Kaplan-type turbine having movable blades an movable gates and which is controlled by a governor and an electronic 3D cam in response to measured values of particular operating parameters, including gross headwater level and power generation level, the improvement comprising:

• an index test apparatus for automatically determining an optimal blade-to-gate positional relationship providing peak generating efficiency for a gross headwater level/power generation level operating condition, said index test apparatus comprising:
• analog-to-digital converting means for converting measured analog values of the operating parameters to digital values;
• memory means for storing both predetermined and measured values of the operating parameters;
• and
• microprocessor means for controlling the automatic determination of the optimal blade-to-gate positional relationships for said turbine, said microprocesor having a program for collecting measurements of the on-cam values of said operating parameters and storing said values in memory;
• evaluating the measured data to determine whether the turbine is operating at steady-state;
• when steady-state operation is achieved, moving the blades of said turbine through a series of off-cam incremental variations in pitch in both flatter blade angle and steeper blade angle directions;
• after making each incremental variation in the blade pitch, allowing the governor to reposition the gates as as to return the power generation level of the turbine to a predetermined setpoint, monitoring the operation of the turbine to determine when it has returned to steady-state and then measuring the values of the operating parameters at the new gate-blade operating point and storing those values in memory;
• computing for each gate-blade operating point a corresponding power generation efficiency value and storing that value in memory;
• comparing each power generation efficiency value with previously computed values which have been stored in the memory to identify a peak efficiency value and thereby define the optimal blade-to-gate positional relationship for said gross headwater level/power generation level operating condition;
• and, upon defining said optimal relationship, returning the turbine to on-cam operation.

In a system for testing a hydro-powered Kaplan-type turbine having movable blades and movable gates and which is controlled by a governor and an electronic 3D cam in response to measured values of particular operating parameters, including gross headwater level and power generation level, the improvement comprising:

• an index test apparatus for automatically determining an optimal blade-to-gate positional relationship providing peak generating efficiency for a gross headwater level/power generation level operating condition, said index test apparatus comprising:
• analog-to-digital converting means for converting measured analog values of the operating parameters to digital values;
• memory means for storing both predetermined and measured values of the operating paramtters;
• and
• microprocessor means for controlling the automatic detemination of the optimal blade-to-gate positonal relationships for said turbine, said microprocessor having a program for collecting measurements of the on-cam values of the operating parameters and storing said values in memory;
• evaluating the measured data to determine whether the turbine is operating at steady-state;
• when steady-state operation is achieved, comparing measured values of the operating parameters with previously measured and stored values to locate unique on-cam operating points;
• upon locating a unique on-cam operating point, making a series of incremental off-cam variations in the pitch of the blades of the turbine in both flatter blade angle and steeper blade angle directions;
• after making each incremental variation in the blade pitch, allowing the governor to reposition the gates so as to return the power generation level of the turbine to a predetermined setpoint, monitoring the operation of the turbine to determine when it has returned to steady-state and then measuring the values of the operating parameters at the new gate-blade operating point and storing those values in memory;
• computing for each gate-blade operating point a corresponding power generation efficiency value and storing that value in memory;
• comparing each power generation efficiency value with previously computed values which have been stored in the memory to identify a peak efficiency value and thereby define the optimal blade-to-gate positional relationship for said gross headwater level/power generation level operating condition;
• and, upon defining said optimal relationship, returning he turbine to on-cam operation.