Methods and systems for controlling turbine powered system to reduce startup time

A power plant comprising:

• a turbine;
• a heat recovery system;
• a bypass stack;
• an exhaust duct including a damper configured to selectively direct the flow of exhaust from the turbine to the heat recovery system or to the bypass stack;
• and
• a processing system, including at least one processor, the processing system being configured to at least:
• before flame out during fired shutdown of the turbine, control the damper to move from a first position directing turbine exhaust to enter the heat recovery system to a second position to allow the turbine exhaust to enter the bypass stack and block the turbine exhaust to the heat recovery system;
• while the position of the damper is maintained in the second position to prevent gas and/or vapor to enter the heat recovery system, perform fired shutdown of the turbine;
• in response to request to start the turbine, determine whether a damper sealing air pressure is continuously maintained from when the damper was moved from the first position to the second position and until the request to start the turbine is received;
• upon determining that the damper sealing air pressure was continuously maintained from when the damper was moved from the first position to the second position and until the request to start the turbine is received, generate air flow in the exhaust duct for a predetermined period of time while the position of the damper is maintained in the second position and start the turbine without performing a purge sequence for the heat recovery system;
• upon determining that the damper sealing air pressure was not continuously maintained from when the damper was moved from the first position to the second position and until the request to start the turbine is received, start the turbine after generating air flow in the exhaust duct for the predetermined period of time while the position of the damper is maintained in the second position and after performing the purge sequence for the heat recovery system while the position of the damper is maintained in the first position;
• and
• after starting the turbine, control the damper to move from the second position to the first position to allow the turbine exhaust to enter the heat recovery system and to block the turbine exhaust to the bypass stack.