Control for improved thermal performance of a steam turbine at partial load

A system that is part of a combined cycle power plant having at least one gas turbine, at least one heat recovery steam generator, and at least one steam turbine, the computer system comprising:

• memory that stores data;
• and
• a processor that executes instructions, at least some of the instructions being in the form of a method for controlling at least a portion of the combined cycle power plant, the method comprising the steps of:
• developing an actual operating curve of a steam characteristic of the at least one heat recovery steam generator versus an amount of steam provided to the at least one steam turbine from the at least one heat recovery steam generator, the actual operating curve being stored as data in the memory;
• determining the steam characteristic of the at least one heat recovery steam generator at a point in time during operation of the combined cycle power plant;
• and
• providing an amount of the steam from the at least one heat recovery steam generator to the at least one steam turbine depending upon the determined steam characteristic of the at least one heat recovery steam generator at the point in time.

A computer program product, comprising:

• a computer-readable computer program code for controlling at least a portion of a combined cycle power plant having at least one gas turbine, at least one heat recovery steam generator, and at least one steam turbine;
• and
• instructions for causing a computer to implement a method for controlling at least a portion of the combined cycle power plant, the method further comprising the steps of:
• developing an actual operating curve of a steam characteristic of the at least one heat recovery steam generator versus an amount of steam provided to the at least one steam turbine from the at least one heat recovery steam generator;
• determining the steam characteristic of the at least one heat recovery steam generator at a point in time during operation of the combined cycle power plant;
• and
• providing an amount of the steam from the at least one heat recovery steam generator to the at least one steam turbine depending upon the determined steam characteristic of the at least one heat recovery steam generator at the point in time.