Functional block diagram of the DTRV/T3R relay
General presentation
The DTRV/T3R relay is an intelligent electronic device (IED) for protection and control dedicated to three-winding transformers, fitted with an automatic voltage regulator; this relay offers complex protection, control and monitoring functions for three-winding power transformers. The DTRV/T3R also integrates a tap changer controller for the voltage regulation of power transformers equipped with a motor-driven on-load tap changer (OLTC). This device belongs to the DTRV product family within the PROTECTA range. In both hardware and software terms, this range is based on a modular architecture.
The DTRV relays are specially designed for the protection and control of power transformers. In addition, the DTRV family integrates a wealth of versatile protection functions to meet the most demanding user requirements.
A voltage regulator can be integrated in the same device together with the protection functions, or provided as a stand-alone IED. Voltage regulation can be performed automatically or, in manual mode, substation staff can set the network voltage according to particular requirements. The intelligent voltage control function can manage up to 4 transformers in parallel, based on minimum circulating current or on the master-slave principle.
Thanks to its built-in control, measurement and monitoring functions, the IED can also be used as a bay control unit.
The EuroCAP configuration software, available free of charge, provides a user-friendly and flexible application for protection, control and measurement functions, allowing the use of fully customisable devices.
General features
- Native intelligent electronic device (IED) compliant with the IEC 61850 standard, Edition 2 compatible
- Scalable hardware adapting to different applications
- Rack width of 84TE or 42TE (height: 3U)
- The predefined factory configuration can be customised to the user’s specifications with the powerful EuroCAP tool
- Flexible protection and control functionalities to meet specific user requirements
- Advanced HMI functionalities via a colour touch screen and a built-in web server, extended measurement, control and monitoring functions
- User-configurable LCD displays, able to show single line diagrams (SLD) with switchgear position indication and control, as well as measurement values and several types of controllable objects.
- Various protection setting groups available
- Enhanced circuit breaker monitoring and control
- High-capacity disturbance recorder (DRE) and event logging (data stored in non-volatile memory):
- DRE supporting up to 32 analogue signal channels and 64 digital signal channels.
- The event recorder can store more than 10,000 events.
- Several mounting methods: rack-mounted; flush-mounted; semi-flush-mounted; wall-mounted; wall-mounted with terminals; flush-mounted with IP54-rated cover.
- Wide range of communication protocols
- Ethernet communication: IEC 61850; IEC 60870-5-104; DNP3.0 TCP; Modbus TCP
- Serial communication: DNP3.0; IEC 60870-5-101/103; MODBUS, SPA
- The PROTECTA range can handle several communication protocols simultaneously.
- Built-in self-monitoring function to detect internal hardware or software errors.
- Various time sources available: NTP server; minute pulse; legacy protocol master; IRIG-B000 or IRIG-B12X
Applications
The DTRV/T3R relay is designed to act as the main intelligent electronic device (IED) for protection and control of three-winding power transformers. The device also integrates a voltage regulator. This relay belongs to the DTRV family within the PROTECTA range.
The DTRV/T3R IED offers a varied range of versatile protection functions in addition to the transformer differential protection, such as three-phase, Io and I² overcurrent protection, thermal overload protection, restricted earth fault (REF) or earth differential protection against earth faults (low or high impedance option), etc.
The multiple three-phase and residual overcurrent functions implemented allow separate protection of the two transformer windings. In addition, several voltage-based protection functions are available for the voltage-controlled side of the transformer, from the three-phase voltage measurement. It can be used as a back-up protection relay for downstream equipment (for example feeders and cables).
The DTRV/T3R transformer protection relay supports two-circuit-breaker schemes on each side of the transformer, such as breaker-and-a-half or ring bus topologies.
Automatic compensation of the phase shift and transformation ratio for all types of transformer winding connections.
The relay integrates a wide range of control and supervision functions, providing full control and user-defined interlocking schemes for the switchgear of the transformer substation.
Field of application
- Protection and control device for three-winding transformers, including a main transformer differential protection and several additional protection functions; voltage control is integrated in the relay.
- The protection functions implemented provide back-up protection for downstream equipment (for example distribution lines, cables, etc.).
- Protection for all types of power transformers.
- Single-phase/three-phase tripping and support for two-circuit-breaker schemes, such as breaker-and-a-half or ring bus topologies
- Three-phase transformer differential protection:
- Automatic compensation of the phase shift and transformation ratio of the transformer.
- 2nd and 5th harmonic restraint for inrush current and transformer overexcitation detection
- A residual current elimination function is available if the transformer has a neutral earthing inside the protected zone, on one of its secondaries.
- Sensitive and restricted earth fault (REF) protection against single-phase faults
- Several voltage-based protection functions are available thanks to the three-phase voltage measurement.
- Current transformer (CT) current unbalance detection
- Voltage regulation with automatic tap changer controller:
- For up to 4 transformers in parallel, based on minimum circulating current or on the master-slave principle,
- Tap changer position read through RTD, mA or binary inputs
- Binary input coding types: binary, BCD, Gray.
- Programmable interlocking schemes
- Optional units:
- 28-input / 5-output tap changer transcoder (TRCS)
- Remote I/O unit (RIO)
- Transducer I/O (RTD/mA)
- Underimpedance protection
Protection and control functions
The DTRV/T3R device measures the three phase currents as well as the residual current (image of the zero sequence current) on both sides of a three-phase three-winding transformer, as well as the three phase voltages. In addition to the current- and voltage-based functions, these measurements allow the directionality of the residual overcurrent function to be extended.
Voltage control is integrated in the same device, as are the main transformer differential protection and the restricted earth fault protection against earth faults.
The main functions of the relay are the transformer differential protection and the restricted earth fault protection against earth faults. The additional protection functions can provide back-up protection for downstream equipment (for example distribution lines and cables).
Click on the link to download the general documentation : Please contact our Sales Department
Technical sheet : NC_DTRV
Operation manual : DTRV_T3R_FDE20GJ0791405A1
Click on the link to access the technical documentation to attach to your order : DOCACOM_PROTECTA
