Study On Frequency-Domain Data Fusion Of Dynamic Thermal Performance Computation

Currently, the fast development of power industry accelerates the development of national economy. And it also set higher requirements to the on-line performance monitoring system. However, the load is changing with time when the units in the electric power system, it means the load of steam turbine is changing at any moment when it running. Thus, taking advantage of the real-time efficiency appears to be particularly important.The relative internal efficiency is computed by thermal balance equation in the real-time monitoring system existed. However, the extracted steam flux is not satisfying the heat balance equation because of the effect of regenerator and pipes'volume in the progress of load change. Dynamic computation error of extracted steam flux, result in error of extracted steam flux of each stage. So, we need to find a dynamic algorithm to calculate the extracted steam flux in order to obtain an accurate extracted steam flux.I have done these works below based on the idea above:First, in-depth analysis of the progress of the reheat unit load change, we knew the error reason and source of relative internal efficiency, that is the error bring about by heat balance equation computing.Secondly, I have constructed the mode of reheat turbine in consideration of regenerator system, compiled MATLAB procedures for extracted steam flux computing. Obtain the complementary frequency property of two signals of extracted steam flux through analyzing.Finally, have designed a complementary filter based on data fusion, and use it to compute the dynamic extracted steam flux, and then to compute relative internal efficiency, compare it with that efficiency compute by thermal balance equation, made a conclusion that the method based on data fusion is much better than that based on heat balance equation.This thesis focused on the research to obtain a dynamic algorithm based on data fusion to calculate the extracted steam flux, and validated by simulation experiments. This method can be used to solve those problems that errors existed in the dynamic progress of computing the extracted steam flux based on thermal balance equation, and has great significance in project using.