Grid searching method in spherical coordinate for PD location in a substation

Partial Discharge(PD) can be located by using algorithms based on Time Difference of Arriving signals (TDOA). A novel grid searching method in spherical coordinate system is proposed to further foster its strengthens in raise angle location, which is theoretically analyzed that grid searching method can locate angle of PD with higher resolution than distance, and circumvent its weakness in high computational cost. In this paper, the detailed location process of this novel algorithm is described and simulations are carried out to verify effectiveness of proposed method. The principle of accurate angular positioning is introduced in detail, and the simulation of different delay errors and grid division is carried out. It is found that the positioning accuracy decreases with the increase of delay error. Compared with cartesian coordinate system, the angular orientation in spherical coordinate system is more accurate and the calculation quantity is lower. The optimal grid partition parameters are given. Application example in a substation also shows the high reliability in angle location and practicability