ABB REF615 feeder protection relay

ABB REF615 feeder protection relay

Product overview

Positioning and Function: REF615 is a specialized feeder protection relay designed for feeder protection, measurement, and monitoring in public substations and industrial power systems. It follows the IEC 61850 standard and supports multiple communication protocols. It can serve as the main protection for overhead lines and cable feeders, as well as backup protection.

Adaptation scenario: According to the pre configuration, it is suitable for the protection of overhead lines and cable feeders in isolated neutral points, resistance grounding, compensation, and solid grounding networks. After specific application settings are given, it can be directly put into use.

Standard configuration

Four configuration types: standard configuration A, B, C, D, supporting different combinations of protection functions, such as configuration A and B supporting directional ground fault protection, and configuration C and D supporting non directional ground fault protection.

Functional differences: Different configurations have differences in the stage settings and directionality of protection functions such as overcurrent, ground fault, and negative sequence overcurrent, as well as varying degrees of support for control, monitoring, and measurement functions.

Protection function

Core protection functions: including three-phase non directional overcurrent (low setting, high setting, instantaneous stage), directional and non directional grounding faults (low setting, high setting, instantaneous stage), negative sequence overcurrent, phase discontinuity, thermal overload, circuit breaker fault protection, three-phase surge detection, arc protection, etc.

Arc protection: Equipped with three optical detection channels through optional hardware and software, it is used for arc fault protection of circuit breakers, busbars, and cable rooms in metal enclosed indoor switchgear, quickly tripping to improve personnel safety and limit equipment damage.

Application scenarios

Grounding system adaptation: Directional grounding fault protection is mainly used for isolated or compensated networks, while non directional grounding fault protection is suitable for direct or low impedance grounding networks.

Substation protection application: In substations, different configurations can be used for overcurrent and ground fault protection of incoming and outgoing feeders, and system protection is achieved through the combination and interlocking of protection functions.

Control and Measurement

Control function: Provides circuit breaker control, including basic interlock and extended interlock, supports automatic reclosing of circuit breakers, and interlock schemes can be configured through the signal matrix tool of PCM600.

Measurement function: Continuously measure phase current, symmetrical component of current, residual current, and if directional grounding fault protection is included, measure residual voltage to calculate maximum demand, thermal overload, and phase imbalance values. The measured values can be accessed locally or remotely.

Fault recording and monitoring

Disturbance recorder: With up to 12 analog and 64 binary signal channels, it can set trigger conditions, record waveforms or trends, and store them in non-volatile memory for fault analysis.

Event log: stores 50 timestamp event codes, non-volatile memory retains data in case of loss of auxiliary power supply for analysis before and after faults.

Circuit breaker monitoring: Monitor the spring charging time, SF6 gas pressure, travel time, and inactivity time of the circuit breaker, and provide operational historical data for preventive maintenance scheduling.

Communication and Interface

Communication protocol: Supports IEC 61850 (including GOOSE messages) and Modbus ®， IEC 61850 supports horizontal communication, Modbus supports RTU, ASCII, and TCP modes, and supports SNTP and IRIG-B time synchronization.

Interface types: including 100BASE-TX RJ45, 100BASE-FX LC fiber optic, and RS-485 interfaces to meet different communication needs.

Technical Parameter

Physical characteristics: Width 177mm, height 177mm (4U), depth 155mm, weight 3.5kg, protection level front panel IP54, top IP40, back IP20.

Power supply: There are various types of auxiliary power supplies with a wide voltage range, low power consumption, and the ability to withstand power interruptions.

Input/output: Current input supports multiple rated values, voltage input can be configured, binary input and output contacts can be freely configured, and I/O expansion modules are supported.

Environmental adaptability: Operating temperature -25 ℃~+55 ℃, storage temperature -40 ℃~+85 ℃, adaptable to various environmental conditions, passed EMC, insulation, and mechanical tests.

Display and installation

Display options: Provide small-sized and large-sized LCD displays, with large-sized displays reducing menu scrolling and improving information overview.

Installation method: Supports various installation methods such as flush installation, semi flush installation, wall mounted installation, 19 inch rack installation, etc. It can be installed at a tilt of 25 ° and is equipped with a test switch.

Working principle

Signal acquisition and processing: Collect current and voltage signals in the power system through devices such as phase current transformers, residual current transformers, and voltage transformers. Process the collected analog signals, such as filtering, amplification, etc., convert them into digital signals for analysis and calculation, obtain electrical quantity information such as phase current, current symmetry component, residual current, residual voltage, etc., and provide data support for subsequent protection and measurement functions.

Protection function action logic

Overcurrent protection: Real time monitoring of current signals. When the current exceeds the preset overcurrent protection value, according to the set time curve (timed or inverse time limit), the protection action is triggered after reaching the corresponding time, such as issuing a trip command to cut off the circuit breaker and protect the equipment from overload current damage.

Grounding fault protection: For directional grounding fault protection, the fault direction and current magnitude are calculated using phase current and residual voltage, and action is taken when the fault direction and current exceed the set values; Non directional grounding fault protection is mainly judged based on the magnitude of residual current, and if it exceeds the set value, the protection will be triggered.

Other protections: Negative sequence overcurrent protection monitors negative sequence current and activates when it exceeds the threshold; Phase discontinuity protection detects the relationship between phase currents to determine faults; Thermal overload protection simulates the heating process of equipment, calculates heat accumulation based on current and time, and starts protection when the set temperature is reached; Three phase inrush current detection identifies inrush current by analyzing the proportion of current harmonics, and takes action when it exceeds the set value; Arc protection uses light detection channels to monitor arc light, combined with current to determine faults, and quickly trips when conditions are met.

Control and monitoring mechanism

Circuit breaker control: The opening and closing operation of the circuit breaker is controlled by internal logic and external input signals, with basic interlocking and extended interlocking functions to prevent misoperation and ensure safe and reliable operation.

Monitoring function: Continuously monitor the status of circuit breakers, such as spring charging time, SF6 gas pressure, etc; Monitor the integrity of the trip circuit, detect open circuits and control voltages; Self monitor its own hardware and software, issue alerts in case of malfunctions, and take corresponding measures.

Communication and Interaction: Supports communication protocols such as IEC 61850 and Modbus for data exchange with other devices. Upload the collected electrical quantity data, event records, fault information, etc. to the monitoring system, receive control instructions and configuration parameters issued by the monitoring system, and achieve remote monitoring and configuration. Support time synchronization function to ensure the accuracy of event recording and data collection, facilitating fault analysis and system operation management.