Overview
The “Transformer differential protection” function detects ground faults and multiphase short-circuits in transformers, reactors, short lines, as wells as
generators and motors. It is appropriate for block protection for generator-transformer blocks, transformer-reactor combinations or transformer-neutral reactors.
For more detailed information on “Transformer differential protection” function, refer to SIPROTEC 5 devices, V8.30 & higher manuals.
To see other supported functions, click here.
Structure/Embedding of the Function
Setting Parameters
Setting parameters for Transformer differential protection
| Addr. | Parameter | C | Setting Options | Default Setting |
| General | ||||
| _:2311:186 | General:Protection Mode | Transformer Current node |
Transformer | |
| _:2311:100 | General:Meas. gnd. current side 1 | no yes |
no | |
| _:2311:101 | General:Meas. gnd. current side 2 | no yes |
no | |
| _:2311:102 | General:Meas. gnd. current side 3 | no yes |
no | |
| _:2311:103 | General:Meas. gnd. current side 4 | no yes |
no | |
| _:2311:104 | General:Meas. gnd. current side 5 | no yes |
no | |
| _:2311:181 | General:Meas. gnd. curr. autosides | no with CT 1ph with CT 3ph |
no | |
| _:2311:182 | General:Meas. gnd. curr. comp.side | no yes |
no | |
| _:2311:191 | General:Reference side is | not assigned Side 1 Side 2 Side 3 Side 4 Side 5 |
not assigned | |
| _:2311:151 | General:MU-ID Side 1 Mp3ph 1 |
0 to 100 | 0 | |
| _:2311:152 | General:MU-ID Side 1 Mp3ph 2 |
0 to 100 | 0 | |
| _:2311:153 | General:MU-ID Side 1 Mp3ph 3 |
0 to 100 | 0 | |
| _:2311:154 | General:MU-ID Side 1 Mp3ph 4 |
0 to 100 | 0 | |
| _:2311:155 | General:MU-ID Side 1 Mp1ph | 0 to 100 | 0 | |
| _:2311:156 | General:MU-ID Side 2 Mp3ph 1 |
0 to 100 | 0 | |
| _:2311:157 | General:MU-ID Side 2 Mp3ph 2 |
0 to 100 | 0 | |
| _:2311:158 | General:MU-ID Side 2 Mp3ph 3 |
0 to 100 | 0 | |
| _:2311:159 | General:MU-ID Side 2 Mp3ph 4 |
0 to 100 | 0 | |
| _:2311:160 | General:MU-ID Side 2 Mp1ph | 0 to 100 | 0 | |
| _:2311:161 | General:MU-ID Side 3 Mp3ph 1 |
0 to 100 | 0 | |
| _:2311:162 | General:MU-ID Side 3 Mp3ph 2 |
0 to 100 | 0 | |
| _:2311:163 | General:MU-ID Side 3 Mp3ph 3 |
0 to 100 | 0 | |
| _:2311:164 | General:MU-ID Side 3 Mp3ph 4 |
0 to 100 | 0 | |
| _:2311:165 | General:MU-ID Side 3 Mp1ph | 0 to 100 | 0 | |
| _:2311:166 | General:MU-ID Side 4 Mp3ph 1 |
0 to 100 | 0 | |
| _:2311:167 | General:MU-ID Side 4 Mp3ph 2 |
0 to 100 | 0 | |
| _:2311:168 | General:MU-ID Side 4 Mp3ph 3 |
0 to 100 | 0 | |
| _:2311:169 | General:MU-ID Side 4 Mp3ph 4 |
0 to 100 | 0 | |
| _:2311:170 | General:MU-ID Side 4 Mp1ph | 0 to 100 | 0 | |
| _:2311:171 | General:MU-ID Side 5 Mp3ph 1 |
0 to 100 | 0 | |
| _:2311:172 | General:MU-ID Side 5 Mp3ph 2 |
0 to 100 | 0 | |
| _:2311:173 | General:MU-ID Side 5 Mp3ph 3 |
0 to 100 | 0 | |
| _:2311:174 | General:MU-ID Side 5 Mp3ph 4 |
0 to 100 | 0 | |
| _:2311:175 | General:MU-ID Side 5 Mp1ph | 0 to 100 | 0 | |
| _:2311:185 | General:MU-ID Mp1ph | 0 to 100 | 0 | |
| _:2311:187 | General:Use tap-changer position | no yes |
yes | |
| General | ||||
| _:11041:1 | I-DIFF:Mode | off on test |
off | |
| _:11041:2 | I-DIFF:Operate & flt.rec. blocked | no yes |
no | |
| _:11041:6 | I-DIFF:Operate delay | 0.00 s to 60.00 s | 0.00 s | |
| Operate curve | ||||
| _:11041:3 | I-DIFF:Threshold | 0.05 I/IrObj to 2.00 I/IrObj | 0.20 I/IrObj | |
| _:11041:100 | I-DIFF:Slope 1 | 0.00 to 0.80 | 0.30 | |
| _:11041:101 | I-DIFF:Intersection 1 Irest | 0.00 I/IrObj to 5.00 I/IrObj | 0.67 I/IrObj | |
| _:11041:102 | I-DIFF:Slope 2 | 0.25 to 0.95 | 0.70 | |
| _:11041:103 | I-DIFF:Intersection 2 Irest | 1.00 I/IrObj to 20.00 I/IrObj | 2.50 I/IrObj | |
| Starting detection | ||||
| _:11041:106 | I-DIFF:Starting detection | no yes |
no | |
| _:11041:107 | I-DIFF:Thresh. startup detection | 0.1 I/IrObj to 2.0 I/IrObj | 0.1 I/IrObj | |
| _:11041:108 | I-DIFF:Factor increasing char. | 1.0 to 5.0 | 2.0 | |
| _:11041:109 | I-DIFF:Max. perm. Start. time | 0.1 s to 180.0 s | 5.0 s | |
| DC offset detection | ||||
| _:11041:110 | I-DIFF:Factor increasing char. DC | 1.0 to 5.0 | 2.3 | |
| Inrush blocking | ||||
| _:11041:115 | I-DIFF:Blocking with 2. harmonic | no yes |
yes | |
| _:11041:116 | I-DIFF:2nd harmonic content | 10% to45% | 15 % | |
| _:11041:117 | I-DIFF:Crossblock. time 2nd har. | 0.00 s to 200.00 s; ∞ | 0.00 s | |
| _:11041:118 | I-DIFF:Blocking with CWA | no yes |
yes | |
| Overexcit. blocking | ||||
| _:11041:121 | I-DIFF:Blocking with 3rd harm. | no yes |
no | |
| _:11041:122 | I-DIFF:3rd harmonics content | 10 % to 80 % | 30 % | |
| _:11041:123 | I-DIFF:Crossblock. time 3rd har. | 0.00 s to 200.00 s; ∞ | 0.00 s | |
| _:11041:124 | I-DIFF:Blocking with 5th harm. | no yes |
no | |
| _:11041:125 | I-DIFF:5th harmonics content | 10 % to 80 % | 30 % | |
| _:11041:126 | I-DIFF:Crossblock. time 5th har. | 0.00 s to 200.00 s; ∞ | 0.00 s | |
| _:11041:127 | I-DIFF:Limit Idiff 3., 5. harmonics | 0.5 I/IrObj to 20.0 I/IrObj | 1.5 I/IrObj | |
| Ext. fault detection | ||||
| _:11041:128 | I-DIFF:Threshold add-on stabiliz. | 1.00 I/IrObj to 20.00 I/IrObj | 2.00 I/IrObj | |
| _:11041:129 | I-DIFF:Time of add-on stabiliz. | 0.00 s to 5.00 s; ∞ | 0.30 s | |
| _:11041:130 | I-DIFF:Crossblk. time add-on st. | 0.00 s to 2.00 s; ∞ | 0.30 s | |
| I-DIFF fast | ||||
| _:11071:1 | I-DIFF fast:Mode | off on test |
off | |
| _:11071:3 | I-DIFF fast:Threshold | 0.5 I/IrObj to 35.0 I/IrObj | 7.5 I/IrObj | |
| _:11071:6 | I-DIFF fast:Operate delay | 0.00 s to 60.00 s | 0.00 s | |
| _:11071:100 | I-DIFF fast:Operate & flt.rec. blocked | no yes |
no | |
| I-DIFF unrestr | ||||
| _:18002:1 | I-DIFF unrestr:Mode | off on test |
off | |
| _:18002:3 | I-DIFF unrestr:Threshold | 0.5 I/IrObj to 35.0 I/IrObj | 10.0 I/IrObj | |
| _:18002:6 | I-DIFF unrestr:Operate delay | 0.00 s to 60.00 s | 0.00 s | |
| _:18002:100 | I-DIFF unrestr:Operate & flt.rec. blocked | no yes |
no | |
Logic Diagrams & highlights
Basic Principle of Differential Protection Using the Example of 2 Sides
Current Stabilization
Principle Current Course in External Short Circuit and Temporary Current Transformer Saturation on One Side
Typical Inrush Current Curve
Logic Diagram of the Transformer Differential Protection Function
Operate Curve of the Transformer Differential Protection Function
Connection and Basic Structure for the Example of a Two-Winding Transformer Yd5
Absolute-Value Correction
Tap-Changer Adaptation
Vector-Group Correction
Vector-Group Adaptation with the Example of Yd5 without Accounting for the Absolute-Value Adaptation
Vector-Group Adaptation with the Example of Yd5
Vector-Group Adaptation for the Example of YNd5
Example of Ground Fault Outside of the Grounding Transformer within the Protection Range with Current Distribution
Auto Transformer with Grounded Neutral Point
Auto Transformer Bank with Current Transformer in the Neutral-Point Feed
Currents calculation
Pickup Characteristic of the Differential Protection
Inrush Current with Pronounced Flat Areas
Logic Inrush-Current Detection
Behavior under Different Fault Conditions
Increasing the Characteristic Curve after DC Detection
Logic DC Detection
Logic Startup Detection
Characteristic Curve Increase at Startup
Trip Logic of I-DIFF
Instantaneous-Value Method calculation
Characteristic Curve of I-DIFF Fast
Curve Plot for Primary Currents in the Event of an External Short Circuit with Transformer Saturation
Curve Plot for the Differential Current and Restraint Current irest · 0.8 in the Event of an External Short Circuit with Transformer Saturation
Logic of the Differential Protection Function I-DIFF Fast
High-current faults
I-DIFF Unrestrained Characteristic Curve
Logic of the I-DIFF Unrestrained Differential Protection Function
Overall Trip Logic
Matching factor calculation
Rated voltage in case of using a transformer with tap changers
Vector group numeral
Correction value to account for the tap changer
Setting Slope 1 with Tap Changer
Part of the Harmonic in Case of Overexcitation
Transformer Inrush Currents, Typical Data
Connection of a Three-Winding Transformer with Several Measuring Points
Connection of an Auto-Transformer Bank with Stabilizing Winding and Several Measuring points
