Line protection

AQ 250 and AQ 300 series offer a complete solution to transmission and sub-transmission line protection in any voltage level. They include line differential and full scheme distance protection functions.

Line differential protection

In AQ 250 series, the AQ-F255 Feeder and line differential protection devices offer a modular protection and control solution for line differential protection applications that require a large I/O capacity. Communication between the master node and sub-node devices is performed over a smart process bus and it is easy to set. The process bus transfers both standard and user-defined data, and it automatically synchronizes the line differential protection settings from the master node device to the sub-node device. The process bus handles the compensation for delays in communication, which means that no external time synchronization is needed.

Distance protection

Power systems are evolving with the integration of distributed generation, often based on renewable energy sources. This leads to varying load conditions and changing fault current contributions, which can make conventional distance protection more difficult to set correctly and less accurate during operation.

With line segment-based distance protection, protection schemes are easier to adapt and can be set more accurately to match the actual protected line by using the real values of each segment instead of averaged values. This improves resistive reach and fault location accuracy, especially in mixed networks.

_{“Line segment-based differential protection” by Arcteq Relays (https://youtu.be/EUlZ_a_rcIg)}