9-4 D30 Line Distance Protection System GE Multilin9.1 DISTANCE ELEMENTS 9 THEORY OF OPERATION9The ground elements are polarized from either zero-sequence or negative-sequence current as per user-settings to maxi-mize performance in non-homogenous systems. The polarizing current is additionally shifted by the user-selectable non-homogeneity correction angle.f) REVERSE QUADRILATERAL REACTANCE CHARACTERISTIC FOR NON-DIRECTIONAL APPLICATIONSThe reverse quadrilateral reactance characteristic is achieved by checking the angle between:AB phase element: (IA – I B) ZREV – (VA – VB) and (I A – IB) Z REVBC phase element: (I B – I C) Z REV – (VB – VC) and (I B – IC ) Z REVCA phase element: (I C – I A) Z REV – (VC – VA) and (IC – I A) Z REVA ground element: I A Z + I_0 K0 Z REV + IG K0M Z REV – VA and (j I_0 or j I_2A) ej(180 + )B ground element: I B Z + I_0 K0 Z REV + IG K0M Z REV – VB and (j I_0 or j I_2B) ej(180 + )C ground element: I C Z + I_0 K0 ZREV + I G K0M ZREV – V C and (j I_0 or j I_2C) e j(180 + )The ground elements are polarized from either zero-sequence or negative-sequence current as per user-settings to maxi-mize performance in non-homogenous systems. The polarizing current is additionally shifted by the user-selectable non-homogeneity correction angle.g) DIRECTIONAL CHARACTERISTICThe directional characteristic is achieved by checking the angle between:AB phase element: (IA – I B) ZD and (VA – VB)_1MBC phase element: (I B – I C) Z D and (VB – VC)_1MCA phase element: (I C – I A) Z D and (VC – VA)_1MA ground element: I_0 Z D and VA_1MI A_2 Z D and VA_1MB ground element: I_0 Z D and VB_1MI B_2 Z D and VB_1MC ground element: I_0 Z D and VC_1MI C_2 ZD and VC _1MThe characteristic and limit angles of the directional comparator are adjustable independently from the mho and reactancecomparators. The directional characteristic improves directional integrity of the distance functions.h) RIGHT BLINDERThe right blinder characteristic is achieved by checking the angle between the following signals:AB phase element: (IA – I B) ZR – (VA – VB) and (IA – IB) ZRBC phase element: (I B – I C) Z R – (VB – VC) and (IB – I C) Z RCA phase element: (I C – I A) Z R – (VC – VA) and (I C – IA) Z RA ground element: I A ZR + I_0 K0 ZR + I G K0M ZR – VA and I A Z R + I_0 K0 Z R + IG K0M Z RB ground element: I B ZR + I_0 K0 ZR + I G K0M ZR – VB and I B Z R + I_0 K0 ZR + IG K0M Z RC ground element: I C Z R + I_0 K0 Z R + I G K0M Z R – VC and I C ZR + I_0 K0 ZR + I G K0M ZRThe blinders apply to the Quad characteristic only.i) LEFT BLINDERThe left blinder characteristic is achieved by checking the angle between the following signals:AB phase element: (IA – I B) ZL – (VA – VB) and (IA – I B) ZLBC phase element: (I B – I C) Z L – (VB – VC ) and (I B – I C) Z LCA phase element: (I C – I A) Z L – (VC – VA) and (I C – IA) ZLA ground element: I A ZL + I_0 K0 ZL + IG K0M Z L – VA and IA Z L + I_0 K0 ZL + IG K0M Z LB ground element: I B ZL + I_0 K0 ZL + IG K0M Z L – VB and I B Z L + I_0 K0 ZL + I G K0M ZLC ground element: I C Z L + I_0 K0 Z L + I G K0M ZL – VC and IC Z L + I_0 K0 Z L + I G K0M ZLThe blinders apply to the Quad characteristic only.
