A METHOD OF OPERATING A TURBINE AND A GAS TURBINE

摘要

The invention provides a gas turbine having a housing and a rotor, at least part of which is mounted in the housing, for rotation about an axis of rotation. An electromagnetic thrust bearing supports the rotor. A counterbalancing chamber is positioned adjacent a downstream end of the rotor into which a high pressure gas can be fed to counterbalance axial loading on the rotor and hence reduce the loading on the bearing. A pressure balancing seal is provided for inhibiting leakage of gas from the counterbalancing chamber. The seal includes two relatively displaceable seal components, one of which is fixed to the rotor thereby permitting the relative spacing between the seal components to be controlled by the electromagnetic bearing.