DEVELOPMENT OF A TORQUE LIMITING DEVICE TO PROVIDE A MEASURE AGAINST GRID BLACKOUT IN GAS TURBINE POWER GENERATING PLANTS

摘要

Gas turbine power generating plants are generally equipped with shear pins to protect the turbine shaft from excessive torque caused by grid blackout, etc. As a substitute for the shear pins, a torque limiting device has been developed. This torque limiting device is an application of the wet process multi-plate clutch. When the generator is subjected to excessive torque, the device slips instantly and protects the turbine shaft. Moreover, if the excessive torque is dissipated, the device connects automatically. Employing this device, it becomes easily possible to take an automatic measure against grid blackout without performing special operations such as parts exchange, and thus the effect of a blackout can be limited to a minimum. As a result of test demonstrations, it has been clearly shown that this torque limiting device can be applied to an aero-derivative gas turbine in addition to an industrial one.