The Study Of Cathode Protection Mathematics Model And Auxiliary Anode Optimization On Grounding Grids

The substation grounding grids is an important equipment in ground working, lightning and protecting, it is also an important part to maintain the safe operation of the power system. The grounding body is always buried in the ground, its subterranean and uneasy to detect of corrosion make hidden danger of power system. Cathode protection is an effective way among so many antiseptic measures to protect grounding grid. This paper will research the grounding grid anode cathode protection mathematics model and optimization as follow:First of all, establish the cathode protection mathematics model. Combined with the characteristics of grounding grids in cathode protection system, put forward reasonable assumptions, the equations describing the corrosion potential in the field should be satisfied and the boundary conditions; method grid potential distribution analytic solution and numerical solution were compared and analyzed, and the finite element numerical method for solving the model.Secondly, establish the auxiliary anode and the potential distribution of grounding system performance model. Through the experimental platform, in accordance with the mouth shape, X shape,□× shape, rice shaped and snake laying auxiliary anode, studied the relationship between the anode and the way of laying grounding surface, drew all kinds of installation of the cathode, anode the best access points, cathode protection mathematics model is adopted to explore the ground area and auxiliary anode parameters such as position, voltage, number of potential and current density distribution and ground grounding grids relationship; presents a regression based on vector similarity and support vector machine(S-SVR) integrated forecast method is applied to the surface potential distribution condition and the grounding grid model.Then, design the auxiliary anode optimization scheme. Based on the numerical calculation of the potential and current distribution, using ANSOFT and MATLAB software package, after establishing auxiliary anode and the grounding surface potential distribution mathematical model, put the uniform distribution of the protection potential as the optimization objective, building the auxiliary anode optimization; through genetic algorithm; the best protection of grounding grid scheme with known specifications was worked out.Finally, analysis the grounding system of cathode protection effect of simulation experiment and engineering example. The experiment platform is set up to verify the cathode protection system; Verified actual protection engineering in two transformer substations of WeiNan. The results show that the design of the auxiliary anode cathode protection model and optimization provide a theoretical reference for the design of guidance and daily maintenance and management of the grounding grid design.