The REL670 Line distance protection is a line distance protection device for power systems, a product of ABB. Here's how:

Functional characteristics

REL670 Line distance protectionProtection function

Distance protection: with five-stage distance protection function for phase-to-phase fault and phase-to-ground fault, measurement and setting are completely independent, optional quadrilateral and ohm circle impedance characteristics, can cooperate with the existing distance protection communication scheme of any power system network, can provide high sensitivity protection, low requirements for remote communication.

REL670 Line distance protectionOvercurrent protection: including general overcurrent protection, negative sequence overcurrent protection, thermal overload protection, etc. Universal overcurrent protection provides additional backup protection; Negative sequence overcurrent protection is used to detect asymmetrical faults in various grounded or ungrounded systems with high sensitivity, and can be used as backup protection for most faults or main protection for ground faults and asymmetrical faults. Thermal overload protection when the line passes the load, jump off the line to avoid the development of more serious faults.

REL670 Line distance protection Other protection: Integrated zero sequence overcurrent protection function, can detect and remove high resistance ground fault; With over excitation protection, voltage differential protection, voltage loss check, underfrequency protection and other functions, respectively, for power transformer or generator overexcitation, voltage differential monitoring, network voltage loss, network underfrequency and other situations.

REL670 Line distance protection Control function: It can provide protection for double-circuit lines, multi-circuit parallel lines and series compensation lines, and can protect and control multiple objects, such as realizing the protection and control of a line and a transformer. It has a powerful interlocking function, and adopts the reservation function to realize the interlocking of intervals and stations. The control is based on the principle of selection before operation, ensuring the reliability of operation and avoiding human error.

REL670 Line distance protection Monitoring and communication functions: comply with IEC 61850 communication standards, support GOOSE horizontal communication, use parallel redundancy protocol (PRP) to improve the reliability of the communication system, and realize zero second recovery in the case of communication failure. The device's integrated human machine interface (HMI) provides a quick view of line operation and system parameters, with shortcuts to relevant important data, and built-in fault and event logging provides important data for post-fault analysis and accident recovery operations.

Usage method

Installation: The REL670 is installed in a suitable position, usually in the protective panel cabinet of the substation. Ensure that the installation position meets the equipment requirements and has good ventilation, moisture-proof and anti-interference conditions. Electrical connection according to the instructions, including the connection of current transformer, voltage transformer and control cable, pay attention to the correctness and firmness of the connection.

Configuration: Access the configuration menu of the device through the dedicated configuration tool or human-machine interface. According to the actual parameters and operation requirements of the power system, set the protection value, such as the impedance value of each section of the distance protection, the time value, the current value of the overcurrent protection, the time value. You also need to set communication parameters, such as IP addresses and communication protocols, to implement communication and data exchange with other devices. In addition, you can set the control functions, such as locking logic and operation permissions, based on the actual application scenario.

Operation and maintenance: After the device is put into operation, real-time monitoring of its operating status, through the man-machine interface or background monitoring system to view a variety of measurement data, protection status information. Verify and maintain the device regularly to check whether the hardware is normal and whether the software version needs to be updated to ensure the performance and reliability of the device. After the failure of the power system, check the fault record and event record of the device in time, analyze the fault cause, and provide the basis for fault handling and system recovery.