Abstract
With further adjustment of economic structure and increase of electricity consumption of the third industry, the peak-valley load difference has been increasing in these years in Shanghai Electric Power Network, and has reached 40% of the total load in 2002. This peak-valley difference has great negative affects on security and dispatching operation of the electric power network. In order to solve this problem, some of large capacity units have to be in two-shift operation. Cyclical thermal stress in unit components was caused due to the unit's starting up, shutting down and changing duty frequently, which led to fatigue life of the material and shorten service life of the unit. Based on this point, a kind of monitor system for the 300MW unit was developed to monitor the operational process and display the calculated temperature, stress and low cycle fatigue life expenditure in real time. The system could recall the temperature, stress values and relative curves for any past time, and help operators to analyze the operation processes of the unit. An example of startup process of a unit was presented to analyze the unsuitable operation. the improving operation was given. As a result, 12 tons oil and 140 minutes of startup time could be saved. The improving startup operation process showed great economic efficiency.
