Indoor Gas Source Location Based On Extended Set-membership Filter

With the continuous progress of industry,gas has been widely used in various fields of industrial applications,has become one of the materials that can not be replaced.However,the danger caused by gas leakage seriously affects people's life and living environment.In this paper,the indoor gas diffusion as the background,using the set-membership filter algorithm to research the gas source location.At last,a feasible area has been get to contain the real location,solving the current use of traditional point estimation algorithm in the gas source location deficiencies.The main work in this paper is outlined as follows.(1)Firstly,the paper discusses the purpose and significance of the research about the gas source location.Introducing the difference between stochastic state estimation and the set-membership filter,shows the advantages of the set-membership filter.The reason why the ellipsoid is used as a feasible set is given,and several commonly algorithms based on ellipsoid set-membership filter are introduced briefly.(2)Secondly,this paper brief discusses the commonly used gas diffusion model.The basis of the selected gas turbulence diffusion model is given.And the extended set-membership filter is introduced into the field of gas source location.Since the set-membership filter requires not only the initial position but also the initial set,nonlinear least squares method is introduced into the gas source pre-positioning and calculating the initial ellipsoid.Accelerating the convergence rate of the set and ensuring the real gas source location is included in the feasible area to improve the credibility.(3)Thirdly,as the gas diffusion is affected by the wind,the information of the wind field is critical to the location of the gas source,and the reality of the wind speed and wind direction measurement is often inaccurate.This paper considers the gas source location algorithm without wind speed and direction.Wind speed and direction can be regarded as the sum of fixed value and random quantities caused by turbulence.The gas diffusion model without wind speed and direction measurement has been established.The extended set-membership filter is used to locating the gas source.(4)Finally,as the gas storage is generally in a limited space,the process of gas diffusion will be blocked by the obstacles.At this moment,the sensors detect the concentration of the gas divided into two parts.One is gas source spreads to the sensors directly.The other is the gas bounded by the obstacles.So,the loss coefficient is introduced to establish the gas diffusion model against one wall and two walls.Simulate and analyze in the Matlab.In addition,the value of the loss coefficient is random,so the loss coefficient is watched as a state variable to improve the robustness of the model.Simulated and compared in the Matlab.