Studies On State Estimation For Networked Systems Under Data Transmission Strategies

Relying on the advanced information technology,the digital oilfield construction has been a future development trend which aims to realize the comprehensive perception of oil-field dynamics,the prediction of oilfield changes,the continuous optimization of oilfield management and the scientific assistance of oilfield decision-making.The real-time mon-itoring of the oilfield ground multi-node production system is an important part of digital oilfield,which is of great significance for oilfield safety production.The real-time state monitoring issue can be described as the state estimation issue for the networked system-s.The estimation problem is one of the research hotspots in the signal processing,which aims to estimate the true states of the system through the measurement information.In gen-eral,the measurements collected by a large number of sensors are transmitted through the communication networks,which may lead to data collisions and congestions due to the in-herent constraints of the network bandwidth.Furthermore,the network-induced phenomena may occur,which will affect the estimation performance of the system.Taking the commu-nication bandwidth limitation as the breakthrough point,this paper is devoted to the state estimation for classical networked systems under several data transmission strategies.The main research content of this paper is divided into three parts.The first part aims to design state estimation methods that can tolerate the influences from the network-induced phenomena under the case that they do occur.By using the Lyapunov theory and the lin-ear matrix inequality technique,effective estimator design methods are given.The second part aims to introduce several data transmission strategies to reduce the occurrence proba-bility of the network-induced phenomena.The purpose of this part is to establish suitable mathematical models to describe the data transmission strategies,and further deal with the state estimation problems for the networked systems under several data transmission strate-gies.Similarly,based on Lyapunov theory and linear matrix inequality technique,feasible estimators are designed.Based on the theoretical results proposed in the second part,the third part combines the encoding-decoding strategy with the free-water dehydrating system of the combined station and further puts forward a state estimation scheme,which realizes the combination of theory and application.Specifically,the research content of this paper includes the following aspects:In the first part,the state estimation problems are discussed for the networked systems based on the incomplete information of the measurements.Specifically,the H_∞state estima-tion problem is firstly investigated in Chapter 2 for a class of artificial neural networks subject to missing measurements with uncertain missing probabilities.Furthermore,the passivity-guaranteed state estimator is designed for a class of delayed artificial neural networks with only partial neurons’information.In the second part,the state estimation problems are discussed for the networked sys-tems under several data transmission strategies.In Chapter 3,the exponentially ultimately bounded estimator design problem is studied for a class of Markovian jumping systems under the Round-Robin protocol.Then,considering the influence of the stochastic communication protocol,the H_∞state estimation problem is dealt with in Chapter 4 for a kind of systems with randomly occurring time-delays.At last,in Chapter 5,for a class of nonlinear systems with sector-bounded constraints,the exponentially ultimately bounded estimator is designed under the encoding-decoding strategy.Based on the theoretical results proposed in the second part,the third part aims to discuss the state estimation problem for the free-water dehydrating system of the combined station under the encoding-decoding strategy.The exploratory attempt of the estimation method based on the encoding-decoding strategy in engineering application not only broadens the solution of the estimation problem for linear system with general form under communica-tion constraints,but also provides a new theoretical guidance for engineering practice.