变电站内水平多层土壤参数反演

发布时间：2018-03-21 05:28

本文选题：接地网　切入点：水平多层土壤　出处：《中国电机工程学报》2014年33期 　论文类型：期刊论文

【摘要】：接地网是变电站的重要组成,起到保障变电站设备安全运行和工作人员安全的作用。IEEE Std80-2000指出,变电站内水平多层土壤的参数分布特性对接地网的接地性能有很大影响。视在电阻率是直接反映水平多层土壤参数的电学指标,因此基于Wenner法建立水平多层土壤的视在电阻率模型是研究其参数特性的重要手段。基于点电流源在水平多层土壤中满足的泊松方程和边界条件,建立了广义积分形式的视在电阻率计算公式;结合Prony展开式和Lipschitz积分得出了有限项求和形式的视在电阻率复镜像表达式。利用视在电阻率测量值和计算值间的均方根误差函数建立了水平多层土壤参数反演模型。采用改进粒子群算法(improved particle swarm optimization,IPSO)拟合不同电极间距离d情况下视在电阻率;优化过程结束后,最小适应度函数对应的粒子被作为最优土壤参数输出。通过与已发表论文中水平两层和三层土壤参数模型对比,验证了所提算法在反演水平多层土壤参数时是有效、可行的。此外,由于测量的视在电阻率是在d10t(d为电极间距,t为电极入地深度)假设下进行简化得出的,所以提出剔除d1 m时无效的视在电阻率测量值的方法来提高水平多层土壤参数估计的精度,该方法也能够对采用Wenner法的视在电阻率现场测量提出指导意见。
[Abstract]:Grounding grid is an important component of substation, which plays an important role in ensuring the safe operation of substation equipment and the safety of staff. IEEE Std80-2000 points out that, The distribution characteristics of horizontal multi-layer soil parameters in substations have a great influence on the grounding performance of ground grids. Apparent resistivity is an electrical index that directly reflects the horizontal multi-layer soil parameters. Therefore, the establishment of apparent resistivity model of horizontal multi-layer soil based on Wenner method is an important means to study its parameter characteristics, based on Poisson equation and boundary conditions satisfied by point current source in horizontal multi-layer soil. A formula for calculating apparent resistivity in the form of generalized integral is established. Combined with Prony expansion and Lipschitz integral, the complex mirror expression of apparent resistivity in the form of finite term summation is obtained. The inversion model of horizontal multi-layer soil parameters is established by using the root mean square error function between apparent resistivity measurements and calculated values. Using improved particle swarm optimization (PSO) algorithm to fit apparent resistivity at different electrode distances (d); At the end of the optimization process, the particles corresponding to the minimum fitness function are output as the optimal soil parameters. It is verified that the proposed algorithm is effective and feasible in retrieving the horizontal multilayer soil parameters. In addition, the apparent resistivity is simplified under the assumption that the electrode spacing is 10 t / d and the electrode depth is at the ground depth. Therefore, a method of eliminating invalid apparent resistivity measurements at d 1 m is proposed to improve the accuracy of the estimation of horizontal multilayer soil parameters. This method can also provide guidance for the field measurement of apparent resistivity using Wenner method.
【作者单位】：输配电装备及系统安全与新技术国家重点实验室(重庆大学);国网浙江省电力公司电力科学研究院;
【基金】：国家自然科学基金项目(51477013) 国家重点基础研究发展计划项目(973项目)(2011CB209401)~~
【分类号】：TM63

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