An on-line measurement method for cable insulation resistance in a GPT's neutral point directly grounded system

摘要

The paper presents a new DC bridge method for on-line measurement of XLPE cable insulation resistance in the case of GPT's neutral point directly grounded. The influence factors that may bring errors are discussed and the ways to reduce errors are given. A lower voltage simulating test is done and the measuring results of the test show that the method is suitable for measurement of insulation resistance of cable.