Research On Parameter Estimation Of Modular High Temperature Gas-cooled Reactor Nuclear Power Plant Model

As a new type of advanced nuclear power plant with the features of Generation Ⅳ nuclear energy system, HTR-PM is based on High Temperature Gas-cooled Reactor-Pebbled Bed Module reactor type, and it is a mainstream reactor type of "The next generation of nuclear power" in the international field of nuclear power. The mode of HTR-PM is "Dual-Modules with One-Turbine(DMOT)" which brings many challenges to the operation optimization, so the application of model-based control and optimization technology will be necessary. Since the accuracy of the model seriously affect the dynamic optimization effect, it is important to use parameter estimation technology to make sure that the model is consistent with the true plant. Based on the analysis results of verification and mismatch simulation, this thesis focus on parameter estimation methods and parameter estimability of HTR-PM steady model and dynamic model.The main research work of the thesis is listed as follows:1. Model simulation, verification and mismatch scenario analysis of HTR-PM are completed. Firstly, both nested sequential method and simultaneous method are applied to the simulation of HTR-PM, the result show that simultaneous method can greatly improve the simulation speed; Then, model verification is applied with the data measured from semi-physical simulation platform of HTR-PM; Finally, mismatch simulation of steady and dynamic parameters are analyzed.2. Analysis methods of parameter estimability in both linear and nonlinear systems are studied, and multi-loads parameter estimation are proposed for steady model of HTR-PM. The definition of parameter estimability and the sufficient conditions for parameter estimation problem are stated. Some methods to improve the estimability of parameters are verified with examples.3. Parameter estimabiliy for dynamic model of HTR-PM under different excitation signals are researched. Firstly, Parameter estimabiliy of a first-order linear system under different input signals are analyzed. Then, multi-parameters estimation proposition for dynamic model of HTR-PM under different excitation signals are established, the solving results show that a good design of excitation signal can not only make the parameters of dynamic model be estimated, but also accelerate the solving speed of the parameter estimation problems; Finally, qualitative and quantitative verification methods are used to verify the modified model of HTR-PM.Finally, a summary of this thesis is given and future research prospect is discussed.