Method for managing a gas turbine assembly at low speed and corresponding gas turbine assembly

• Main Authors: Colley, Stephen, Smith, Michael
• Format: Patent
• Language: English
• Published: 15.10.2019
• Subjects: AIR INTAKES FOR JET-PROPULSION PLANTS; BLASTING; COMBUSTION ENGINES; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS; ENGINE PLANTS IN GENERAL; GAS-TURBINE PLANTS; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; LIGHTING; MACHINES OR ENGINES IN GENERAL; MECHANICAL ENGINEERING; NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAMTURBINES; STEAM ENGINES; WEAPONS

A method manages a gas turbine assembly during start up or shut down, the gas turbine assembly including a twin shaft gas turbine having an input shaft and an output shaft and a speed sensor for measuring a speed of the output shaft, the gas turbine assembly further having a rotor mounted on said output shaft and provided with at least a dry gas seal for preventing leakage of a process gas. The method includes monitoring the speed of the output shaft, and in parallel, reducing or increasing the speed of the input shaft after the monitored speed of the output shaft has remained above zero and below a predefined slow roll speed limit for a predefined acceptable time.