Combined-cycle steam turbine and system having novel cooling flow configuration

A single-shaft combined-cycle turbine comprising:

• a gas turbine;
• a steam turbine including:
• a high-pressure section;
• an intermediate-pressure section adjacent the high-pressure section;
• and
• a low-pressure section adjacent the intermediate-pressure section, the low-pressure section having a plurality of stages, a first of the plurality of stages located furthest from the intermediate-pressure section and a second of the plurality of stages located adjacent and between the first and a third of the plurality of stages;
• a turbine shaft disposed within and between both the gas turbine and the steam turbine;
• and
• a cooling steam flow inlet adjacent the third of the plurality of stages of the low-pressure section.

A steam turbine comprising:

• a high-pressure section;
• an intermediate-pressure section adjacent the high-pressure section;
• and
• a low-pressure section adjacent the intermediate-pressure section, the low-pressure section having a plurality of stages, a first of the plurality of stages located furthest from the intermediate-pressure section and a second of the plurality of stages located adjacent and between the first and a third of the plurality of stages;
• and
• a cooling steam flow inlet adjacent the third of the plurality of stages of the low-pressure section.