Time domain distance protection method and system for new energy transmission line

The invention discloses a time domain distance protection method and system for a new energy transmission line, and the method comprises the steps: building a metal grounding fault model according to a pi-type line, building a fault position function in a time domain range, accumulating the absolute values of the molecular denominators of the fault position function of each sampling interval through employing the equal ratio theorem, and carrying out the accumulation of the absolute values of the molecular denominators of the fault position function; obtaining a fault position correction function; when the power grid breaks down, the fault position is calculated through the fault position correction function, and corresponding protection action is carried out; the method is not influenced by the denominator zero crossing point of the fault position function, numerical calculation near the denominator zero crossing point is stable, and the internal fault can be accurately identified at different fault position