Operation of a wind turbine during start-up to reduce limit cycles

A control system, comprising:

• an input/out interface;
• and
• one or more processors configured to perform an operation for operating a wind turbine system during start-up, the operation, comprising:
• a) setting a nominal cut-in value of a first operational parameter and a connection cut-in value of a second operational parameter of the wind turbine;
• b) monitoring the first operational parameter;
• c) initiating start-up of the wind turbine when the monitored first operational parameter is higher than the nominal cut-in value;
• d) monitoring the second operational parameter;
• e) detecting a cut-in transition if the value of the second operational parameter is not reaching the connection cut-in value within a start-up time period or the first operational parameter falls below the nominal cut-in value;
• f) detecting a cut-in limit cycle of the wind turbine if more than a threshold number of counted cut-in transitions has been detected, and if a cut-in limit cycle is detected, increase the nominal cut-in value;
• and
• g) repeating steps b)-f) until the second operational parameter reaches the connection cut-in value.

A wind turbine system, comprising:

• a tower;
• a nacelle disposed on the tower;
• a rotor extending from the nacelle and having a plurality of blades disposed at a distal end of the rotor;
• and
• a control system for operating a wind turbine system during start-up, the control system configured to perform an operation, comprising:
• a) setting a nominal cut-in value of a first operational parameter and a connection cut-in value of a second operational parameter of the wind turbine;
• b) monitoring the first operational parameter;
• c) initiating start-up of the wind turbine when the monitored first operational parameter is higher than the nominal cut-in value;
• d) monitoring the second operational parameter;
• e) detecting a cut-in transition if the value of the second operational parameter is not reaching the connection cut-in value within a start-up time period or the first operational parameter falls below the nominal cut-in value;
• f) detecting a cut-in limit cycle of the wind turbine if more than a threshold number of counted cut-in transitions has been detected, and if a cut-in limit cycle is detected, increase the nominal cut-in value;
• and
• g) repeating steps b)-f) until the second operational parameter reaches the connection cut-in value.

A computer program product comprising software code adapted to control a wind turbine system when executed on a data processing system, the computer program product being adapted to perform an operation, comprising:

• a) setting a nominal cut-in value of a first operational parameter and a connection cut-in value of a second operational parameter of the wind turbine;
• b) monitoring the first operational parameter;
• c) initiating start-up of the wind turbine when the monitored first operational parameter is higher than the nominal cut-in value;
• d) monitoring the second operational parameter;
• e) detecting a cut-in transition if the value of the second operational parameter is not reaching the connection cut-in value within a start-up time period or the first operational parameter falls below the nominal cut-in value;
• f) detecting a cut-in limit cycle of the wind turbine if more than a threshold number of counted cut-in transitions has been detected, and if a cut-in limit cycle is detected, increase the nominal cut-in value;
• and
• g) repeating steps b)-f) until the second operational parameter reaches the connection cut-in value.