Ultra-high voltage double-circuit-on-same-tower double-circuit line grounding fault relay protection method based on six-sequence component method

The invention discloses an ultra-high voltage double-circuit-on-same-tower double-circuit line grounding fault relay protection method based on a six-sequence component method. The ultra-high voltagedouble-circuit-on-same-tower double-circuit line grounding fault relay protection method comprises the steps of: precisely describing physical characteristics of ultra-high voltage double-circuit-on-same-tower double-circuit lines by adopting distribution parameters and the six-sequence component method; calculating the voltage drop amplitude from an ultra-high voltage double-circuit-on-same-towerdouble-circuit line protection installation position to a grounding fault point; directly calculating a fault impedance amplitude value by utilizing a hyperbolic tangent function relationship betweena fault distance from the ultra-high voltage double-circuit-on-same-tower double-circuit line protection installation position to the grounding fault point and the voltage drop amplitude value; and forming a relay protection c