Gas Turbine Series

The objective for this course is to present the main features of the Gas Turbine Combined Cycle, as employed for “Power Generation”, and “Co-Generation” (process steam of gas to industry). The most common types of configurations are presented along with an examination of typical steam turbine arrangements. Operation and control of the combined unit is also discussed in some detail, with the exception of the HRSG which is demonstrated in course 2509.

Upon completion of this course and associated workbook, the participant should understand and be able to apply the following concepts:

• Awareness of the large amount of heat contained in the exhaust gas
• Recovery of exhaust heat through the HRSG (Heat Recovery Steam Generator)
• The advantage of dual pressure and triple pressure HRSG’s
• Applications of HP steam, IP steam, and LP steam
• Feedwater heating by the economizer
• Final exit gas temperature to the stack
• Effect of gas turbine load reduction on exhaust gas temperature
• Control of air (and gas) flow by inlet guide vanes in order to control exhaust gas temperature
• The use of auxiliary burners to increase gas temperature at the HRSG inlet
• Typical configurations of combined cycle units
• The use of the HRSG gas by-pass
• The use of HRSG steam by-pass to the condenser
• Steam turbine sliding pressure operation, accompanying load changes on the gas turbines
• The use of back pressure turbines to provide steam for process use
• The need for auxiliary boilers where process steam is supplied
• The use of condensing steam turbines with steam extraction for process
• Typical steam turbine arrangements for combined cycle units
• Condenser arrangements
• Re-heat steam turbines for combined cycles
• Steam turbine support systems
• Condenser operation and CW systems
• Gland steam system operation
• Start-up and operation of the combined cycle unit
• Control of pressure raising in the HRSG
• Control of steam temperature at the steam turbine inlet