经验包络法在小电流接地电力电缆在线故障测距中的应用.

The location of the fault is required to be detected in the case of UPS when single - phase - to - earth fault occurs. Aiming at the requirement, a method of online power cable fault location in neutral point ineffectively grounded power system based on EE was proposed. Under the condition that the parameters of cable were unknown, the velocity of traveling wave in cable was measured by the use of switching overvoltage wave which was generated when the closing occurred. When single - phase - to - earth fault happened, EE was used to find the mutations moments of instantaneous frequency. Then the location of power cable fault was determined by one - terminal fault location method. Finally, the digital simulation of an example was made to verify the effectiveness and practicability of this method. [ABSTRACT FROM AUTHOR]