A new measuring method and characteristic of HVDC insulator voltage distribution

A new voltage distribution measuring method on the basis of electrostatic faradism theory is introduced. A specially designed instrument, made up of a micro-rolling-motor detector, a single-chip microcomputer unit and a speaker system, is analyzed. The detector can convert the distributed voltages of HVDC insulators to ac signals to be dealt with by the single-chip microcomputer unit. Characteristics of voltage distribution and some influencing factors are also studied. Three-dimensional voltage distribution curves showed that contamination, air humidity, space charge and the applied voltage polarity have different effects on the voltage distribution. Moreover, the voltage distribution shows a dynamic process, which is greatly different from these factors in the ac case. The current flowing into each insulator is also measured