Power generation: Advanced monitoring, control boost performance
Pittsburgh, PA; Wickliffe, OH —Advanced systems from major automation companies are providing critical monitoring and control capabilities for two power plants using new generation technologies. The installations include Emerson Process Management 's Ovation control system being implemented at China's first 1,000 MW ultra-supercritical power generation units and an ABB distributed control system being applied at a Kentucky power station using circulating fluidized bed (CFB) technology to burn coal and alternative fuels.
The Ovation expert control system from Emerson is helping two new power plant units in China synchronize to the power grid eight months ahead of schedule. Emerson won the $7 million contract to automate the four-unit, 4,000-MW, coal-fired facility in April 2005. The plant, owned by Huaneng Power International Inc., is the first 1,000-MW-per-unit power plant in China and the first in the country to use ultra-supercritical technologies.
Unit 1 successfully completed its 168-hr performance test in fall 2006 to become China's first 1,000-MW ultra-supercritical unit in commercial operation. Unit 2 synchronized to the power grid a few weeks later and completed its 168-hr performance test on Dec. 30, 2006. It is estimated that about 11 billion kWh of electricity will be generated by these two ultra-supercritical units annually. Start-up of Units 3 and 4 (Phase 2 of the project) is slated for 2008.
Emerson's Power & Water Solutions industry center designed the control strategy, and coordinated and supervised the engineering and installation of the Ovation control system, which includes a number of advanced technologies and is a key component of Emerson's PlantWeb digital plant architecture. The system monitors and controls the data acquisition system, modulating control system, sequence control system, furnace safeguard supervisory system, and electrical control system for all major plant components, including the boiler, turbine, generator, and other plant processes.
"We found the Ovation system to be reliable, user-friendly, and efficient—factors that contributed to our ability to put the plant into commercial operation eight months ahead of schedule," said Wu Hechun, a supervisor in Huaneng Power International's instrument and control division. Ovation was designed and built for the power generation industry, notes Emerson.
Ultra-supercritical plants use new advanced clean coal technology that allows operation at elevated steam temperatures and pressures, points out Emerson, adding that such technologies are expected to become more prevalent in China because they can boost the efficiency of coal-based electricity generation by more than 50%, while maintaining environmental performance. Yuhuan Units 1 and 2 are said to be the cleanest, most efficient, and most advanced ultra-supercritical units in the world. The plant's thermal efficiency is more than 45%. (Sub-critical plant thermal efficiency is typically 30-38%.) The system has a fuel conversion rate of less than 288.5 grams/kWh (0.64 lb/kWh).
In separate power generation system news , ABB is providing a distributed control system for East Kentucky Power Cooperative's (EKPC) H.L. Spurlock station in Marysville, KY, which uses CFB technology to burn coal and alternative fuels. The DCS, says ABB, has the capacity to provide quick response to the unique and dynamic nature of CFB applications. The system will monitor and control the station's three existing units, two conventional coal-fired and one CFB. It will also handle the Spurlock Unit 4 currently under construction, which will also use CFB technology. Unit 4 will increase the power station's output by 278 MW to nearly 1,400 MW to meet growing electricity demand in the area. The new unit is scheduled for start-up and commissioning in April 2008.
The two CFB units can burn several million tires a year and 150,000 tons of biomass such as sawdust and other wood products while maintaining low emissions. The units can remove 98% of the sulfur dioxide while producing 80% less nitrogen oxide than conventional coal-fired power generation.
ABB installed DCSs at EKPC's two other coal-fired stations, controls at one of its combustion turbine sites, and a grid dispatch system at its Winchester, KY, headquarters. EKPC is a not-for-profit co-op that provides wholesale electricity to 16 distribution cooperatives, generating power through plants located in Mason, Pulaski, and Clark counties in the state.
—Control Engineering Daily News Desk
Edited by Jeanine Katzel , senior editor