Nonlinear Control Design Of Power System Based On Sum Of Square Method

The power system,as a vital resource for the national economy and the people's livelihood,has become the source of the nerve center and power of the contemporary society and economic operation.People also put forward higher requirements for the sustainable,safe,efficient and stable operation of the power system.With the development of science and technology,the structure and composition of modern power system are diverse and complex.How to effectively improve the stability of power system has become the research focus of researchers.In recent years,with the construction of clean energy grid and so on,Modern power systems urgently require advanced control methods to effectively enhance the stability and robustness of the power system,as well as to improve the transient performance of the power system.Aiming at the single machine infinite power system,we design the excitation controller by sum of square method and policy iteration technology,and study the stability of power system under uncertain disturbance signal.The main contributions are as follows:Chapter one mainly introduces the significance of the stable operation of power system and the preparatory knowledge of excitation control and sum of square method,and briefly introduces the research status of power system and sum of square method,as well as the main work of this paper.In chapter two,the mathematical model of the synchronous generator and the basic definition and theorem of sum of square are introduced in detail.Chapter three takes the single machine infinite power system as the research object,the state feedback excitation controller and output feedback excitation controller are designed to achieve local stability under the condition of no interference signal.Among them,we expand the interior point method to solve bilinear problems in the design process iteratively.At the same time,we use the optimization target?to ensure that every iteration maximizes the system attraction area.In the fourth chapter,the H_? optimal excitation controller is designed for a single machine infinite power system with uncertain interference items.First of all,through the principle of Taylor was launched,and considering the infinite items,and then through the strategy of iterative design of H_?optimal excitation controller.The chapter five is the summary of this article,and the problems that need to be solved in the power system and the sum of square method are put forward.