Asia Power Week 2017

Sessions Speakers Exhibitors Products Press Releases Floor Plan Buzz

Design and Application of Combined Cycle Steam Turbines for High Efficiency and Flexibility (Room Nile 2)

Single shaft applications typically yield the best life cycle evaluation, especially for projects with single gas turbine (GT) and power outputs greater than 150 MW. With the continuous growth in size in heavy duty gas turbines, technology evolution, and the attractive economics of large power plants, we see a market preference for Single Shaft Applications that are fully integrated by the GT OEM. Single Shaft configurations are usually less expensive, particularly at higher output. Steam turbines become a critical component in the integration of the power island train. The steam turbine manages the modifications necessary to integrate the clutch, finalize the rotor dynamic solution, and take into consideration operability requirements in these applications. Modern utility networks require unique combined cycle (CC) solutions to respond to load fluctuations associated with renewable energy sources and power demand throughout the day, while maintaining high efficiency. This paper will review some of the unique steam turbine (ST) system solutions to meet the specific demands of SS CC plants for high flexibility and high efficiency markets, these topics include; First, the application of a clutch between the steam turbine and generator, to increase the range of operating modes for the plant, such as allowing the gas turbine (GT) to operate in simple cycle (SC) mode, to enhanced start up capability, to enabling duct firing for fast power ramps to meet load fluctuations. And second, other design considerations like compactness of design, exhaust configurations, accessories modularization, and constructability features to expand the value to customers.