Energy-loss Analysis of Thermal Power Unit Based on Multifactor Disturbance Theory

Abstract

A new energy-loss analysis based on multifactor disturbance theory was studied in this paper. Due to the strong coupling characteristic of steam turbine system, the disturbance factors were decoupled and categorized. The main steam pressure, main steam temperature, reheat steam temperature and exhaust steam pressure were categorized as the large independent disturbance factors, while the terminal temperature differences (TTDs) of the regenerative heaters were categorized as small independent disturbance factors. The single-factor calculation method for energy-loss of heater TTDs neglected the interaction between each heater, thus all heater should be considered as a whole system when calculating the energy-loss of TTDs changes. The energy-loss of large independent disturbance was calculated based on global variable condition calculation method. Through calculating the energy-loss caused by the classified disturbance factors, the relative errors between the theoretical value and operation value were -3.00% for100%THA (turbine heat acceptance), -9.75 for 75%THA and 16.47% for 50%THA. The relative errors meet the requirements of the onsite guidance.