Digital protection

Protection of busbars and transformers

Figure 1 - Busbar differential protection operating principle

Figure 2 - High impedance differential protection operating principle

Figure 3 - Operating principle of medium-impedance differential protection

Figure 4 - Schematic diagram of Areva-TD&#039;s static, medium-impedance DIFB busbar differential protection measurement system.

Figure 5 - Characteristic curves for DIFB medium-impedance differential protection

Figure 6 - Operating principle of a circuit-breaker failure controller

Figure 7 - Operating principle of directional busbar protection

Figure 8 - Ground-bar protection operating principle

Figure 9 - Unlocking protection system for two-busbar substations and coupling

Figure 10 - Unlocking protection system for ring stations

Figure 11 - Buchholz relay operating principle

Figure 12 - Transformer differential protection (without auxiliary transformers)

Figure 13 - Earth-tank protection

Figure 14 - Comparison of distance protection with electronic (left) and digital (right) static technology.

Figure 15 - Communication diagram according to IEC 61850

Figure 16 - Areva-TD&#039;s PXLN digital protection flowchart (figure given for information only)

Figure 17 - Areva MICOM digital protection architecture

Figure 18 - Triggering characteristic of digital line differential protection

Figure 19 - Example of differential busbar protection in decentralized architecture (source Siemens)

Figure 20 - Example of the front panel of a recent digital protection system