Pitch control of wind turbine blades in a standby mode

A computer program downloadable from a communications network and/or stored on a machine readable storage medium comprising program code instructions for implementing an operation of a wind turbine generator (WTG) comprising a pitch control system, the operation comprising:

• a) operating the WTG in a normal mode while the WTG is connected to an external grid;
• b) controlling the pitch angle of the blades using a normal pitch control mode while the WTG is operating in the normal mode;
• c) detecting a grid loss;
• d) operating the WTG in a standby mode during the grid loss;
• and
• e) controlling the pitch angle of the blades in dependence on a monitored speed parameter of the WTG using a standby pitch control mode different to the normal pitch control mode while the WTG is operating in the standby mode, wherein the standby pitch control mode is less responsive than the normal pitch control mode such that the power consumption of the pitch control system is reduced when the WTG is operating in the standby mode.

A controller, comprising:

• an I/O interface configured to be coupled to a wind turbine generator (WTG) comprising a pitch control system;
• one or more processors which, when programmed with instructions, are configured to perform an operation comprising:
• a) operating the WTG in a normal mode while the WTG is connected to an external grid;
• b) controlling the pitch angle of the blades using a normal pitch control mode while the WTG is operating in the normal mode;
• c) detecting a grid loss;
• d) operating the WTG in a standby mode during the grid loss;
• and
• e) controlling the pitch angle of the blades in dependence on a monitored speed parameter of the WTG using a standby pitch control mode different to the normal pitch control mode while the WTG is operating in the standby mode, wherein the standby pitch control mode is less responsive than the normal pitch control mode such that the power consumption of the pitch control system is reduced when the WTG is operating in the standby mode.