To solve some practical problems existing in fault diagnosis of substation grounding grid

such as time-consuming modeling

heavy workload in field test

etc

basing on Tellegen theorem and least square method

a visual fault diagnosis of grounding grid platform is developed.The automatic generation of grounding grid network topology is realized

the measured port resistance between two grounding down lines is transfered automatically to diagnosis software by RS-232 serial communication interface

and the condition of grounding grid is determined by the incremental resistance of each branch conductor in output interface.The diagnosis platform greatly improve the efficiency of the grounding grid fault diagnosis

and has good engineering practicability.