Prediction And Optimal Control Of Link Quality Of Wireless Sensor Networks For Smart Grid Communication

The smart grid is built on a high-speed two-way communication network.Through advanced sensing technology,control methods,and decision support,the grid can be operated reliably,safely,economically,and efficiently.Wireless sensor networks can provide low-cost,easily expandable basic information channels for smart grids.However,wireless links are susceptible to interference from environmental factors,which affects the reliability of data communications.Through predicting and controlling link quality,and adjusting the signal transmission power,the reliability of wireless communication can be effectively improved.Therefore,the prediction and optimal control of link quality has become one of the hotspots in the field of smart grid wireless communication networks.The main reason why it is difficult to predict and control its reliability is the nonlinearity and randomness of wireless link.To overcome this difficulty,based on the analysis of wireless communication link characteristics in smart grid,a wireless link quality confidence interval prediction algorithm and a fuzzy PID control algorithm are proposed in this thesis,so as to optimize the transmission power of nodes.The main work of this thesis is as follows:(1)Taking the reliability demand of the smart grid for the communication network as the control target,the characteristics of the wireless sensor network communication service quality in the smart grid,the factors affecting the reliability of the wireless sensor network link,and the mathematics of the wireless sensor network link are analyzed.(2)Combined with the mathematical model of the wireless sensor network link of the smart grid,the coupling components of the link quality index and the quality of the wireless communication link are analyzed.A structure of the confidence interval prediction algorithm for the reliability of the wireless communication link is proposed.Introducing the wavelet decomposition algorithm,the stationary part and the noise part of the signal noise ratio characterizing link quality,a link quality confidence interval prediction algorithm based on LSTM neural network is proposed,which verifies the effectiveness and superiority of the proposed algorithm.(3)According to the prediction result of the reliability confidence interval of the wireless communication link,based on the fuzzy PID control algorithm,the reliabilityoptimization control of the communication link of the smart grid wireless sensor network is studied.And through simulation tests,the stability and reliability of the optimized control results proposed in this thesis are verified.The simulation examples of the application in the smart grid show that the wireless link quality confidence interval prediction algorithm and fuzzy PID control algorithm proposed in this thesis can optimize and adjust the node transmit power and ensure the reliability of the smart grid wireless communication link.