用接地电位三次样条插值函数测试接地电阻

New Method for Testing Grounding Resistance via Its Cubic Spline Function

为了克服大型地网接地电阻测量时长距离布线的困难和消除线路互感干扰,提出了一种“利用接地电位的三次样条插值函数测试接地电阻的新方法”。该方法通过近距离测试接地网周围的电位分布变化,利用三次样条插值函数拟合出接地电位的分布曲线,通过接地电位和接地电流计算确定接地电阻。该法测量地网接地电阻时不需要远距离布置电流极,克服了地理条件对长距离布线的限制,消除了长距离布置测试线路引起的互感干扰,而且可以实现在线测量。实测结果表明该测量方法正确,而且使用方便。

In order to overcome the difficulty of long distance leading wire and the interference from the wire, a new method for measuring the grounding resistance of the grounding grid by the cubic spline function of the electric potential distrihution is proposed. This innovative method need measure the changes of electric potential distribution near the grounding grid to simulate the electric potential distribution curve by the cubic spline function. The amount of grounding resistance is calculated by means of the grounded electric voltage determined by this curve and the grounding electric current. It needs not pot a current-electrode far from the grounding grid and lead wire between the current-electrode and the large grounding grid in testing the grounding resistance. This approach can overcome the geographic constraints and remove the interference from the wire. The grounding resistance can be measured although the grounding grid is simultaneously used in power system. The experimental results show that this method can used to correctly and conveniently measure the grounding resistance.