Turbine Hydraulic Control Systems Modeling And Parameter Identification

The DEH system is important and essential for the safe, steady and economical operation of steam turbine. Through identifying the DEH system, we can monitor the operational state and the changes of Unit and predict the performance of DEH system, thus providing important reference for the mid- and long-term steady analysis of electric network and the controlling of the frequency. Therefore the establishment of the model of DEH system and the identification of its parameters are significant for the steady analysis of the electric network.Two parameter identification methods, the correlation method and the least square method, are researched in this paper. In the mean while, we apply them to the establishment of DEH model and its parameter identification of the power plant. The correlation method is the one that computes the frequency response of the components of DEH by utilizing the input and output data, and then calculates the transfer function of the DEH system by using Levy method. The least square method is a classical identification method which is so concise and used so widely that it can be used without much statistic and mathematical knowledge. First, we analyze the precision of the identification procedure in different sampling frequencies and in different input signals through simulation. Then we take these two identification methods into the practical test after ascertaining the appropriate input signal and sampling frequency. By pretreatment of the real data, satisfactory results about the identification are achieved.At present, most studies on parameter identification in China are still limited in research of the simulation and identification methods. In this paper, we have already applied the identification method to practice. Through programming parameter identification software much money is saved and good results are achieved. Although the identification results still have some difference between a computed or measured value and a true or theoretically correct value in practice, the identification in practice achieves its goal in the whole identification process. It has a bright prospect in application.In the end. systemic analyses and summarization on the identification are made in this paper. It also puts forth improvement in the identification in future.