Alstom MiCOM P545 - Page 445

Application Notes P54x/EN AP/La4
MiCOM P543, P544, P545 & P546
(AP) 6-1
AP
CONTENTS
(AP) 6-
1. INTRODUCTION 7
1.1 Protection of overhead line, cable, and hybrid circuits 7
2. APPLICATION OF INDIVIDUAL PROTECTION FUNCTIONS 9
2.1 Differential protection 9
2.1.1 Setting of the phase differential characteristic 9
2.1.2 Relay sensitivity under heavy load conditions 10
2.1.3 CT ratio correction (all models) 11
2.1.4 Transformers in zone applications (P543 & P545 models) 11
2.1.4.1 CT ratio correction 12
2.1.4.2 Phase correction and zero sequence current filtering 12
2.1.4.3 High set differential setting 13
2.1.5 Mesh corner and 1½ breaker switched substations 13
2.1.6 Small tapped loads (tee feeds) 13
2.2 Optional distance protection 14
2.3 Distance protection and aided DEF (Distance option only) 14
2.3.1 Simple and advanced setting mode (Distance option only) 14
2.3.2 Line parameters settings (Distance option only) 14
2.3.3 Residual compensation for earth/ground faults (Distance option only) 14
2.3.4 Mutual compensation for parallel lines (Distance option only) 14
2.3.5 Selection of distance operating characteristic (Distance option only) 15
2.3.5.1 Phase characteristic (Distance option only) 15
2.3.5.2 Ground characteristic (Distance option only) 16
2.3.6 Zone reaches - recommended settings (Distance option only) 16
2.3.7 Quadrilateral phase resistive reaches (Distance option only) 17
2.3.8 Quadrilateral ground resistive reaches and tilting (Distance option only) 18
2.3.9 Phase fault zone settings (Distance option only) 20
2.3.10 Distance directional principle and setup (Distance option only) 20
2.3.11 Delta directional - selection of RCA (Distance option only) 20
2.3.12 Distance setup - filtering, load blinding and polarizing (Distance option only) 21
2.3.12.1 Digital filtering (Distance option only) 21
2.3.12.2 CVTs with passive suppression of ferroresonance (Distance option only) 21
2.3.12.3 CVTs with active suppression of ferroresonance (Distance option only) 21
2.3.13 Load blinding (load avoidance) (Distance option only) 21
2.3.13.1 Recommended polarizing settings (Distance option only) 22
2.3.14 Distance elements basic scheme setting (Distance option only) 22
2.3.15 Power swing alarming and blocking (Distance option only) 23
2.3.16 Out of step protection (Distance option only) 24
2.3.17 Critical stability angle (Distance option only) 24