Electric transmission line interphase fault full-component voltage protection method

The invention discloses an electric transmission line interphase fault full-component voltage protection method. The method realizes electric transmission line interphase short circuit fault full-component voltage protection by utilizing the along-the-line voltage drop distribution characteristic, eliminates the influence of the operating method of the system, transition resistance and load current on the protection action performance, and is suitable for protecting the whole fault process of the electric transmission line interphase fault, wherein the along-the-line voltage drop distribution characteristic is as follows: when the fault occurs in a protection area, the along-the-line voltage drop amplitude from a protection mounting position to an interphase short circuit fault point is less than the voltage drop amplitude from the protection mounting position to a protection setting range; and when the fault occurs outside the protection area, the along-the-line voltage drop amplitude from a protection mounting position to the interphase short circuit fault point is more than the voltage drop amplitude from the protection mounting position to the protection setting range.