Transformer Protection System

​

The T35 is designed to provide basic transformer protection functions for variety of transformer applications. It uses multiple current inputs to provide primary protection and backup protection of transformers, including differential, phase and ground overcurrent. The relay can be configured to accept up to 6 sets of current inputs to provide proper differential restraint for applications with three-winding transformers with windings configured in dual-breaker arrangements.

 

Key Benefits

​

• Secure high-speed transformer differential protection in a cost-effective package

• Improved security for transformer energization and inrush

• Application flexibility for transformers with up to 6 sets of CTs

• Robust network security enabling Critical Infrastructure Protection

• Advanced IEC 61850 Ed. 1 and Ed. 2 certified implementation, complete settings via SCL files and flexible process bus support (IEC 61850-9-2LE, IEC 61869 or IEC 61850-9-2 Hardfiber) ensures interoperability, device managing optimization and reduced cost of ownership

• Routable GOOSE (R-GOOSE) enables GOOSE messages going beyond the substation, which enables wide area protection and control applications

• Advance Cyber security features “CyberSentryTM” that helps meet modern industry requirements

• Application flexibility with multiple I/O options including high density I/O, programmable logic, modularity, and specific customization

• An integrated large, full color display, provides real-time visualization and control of the protected bay, via a bay mimic as well as annunciator functionality and graphical visualization of phasors

​

Applications

​

• Combined protection for transformer and small bus zone, including breaker-and-a-half and ring bus diameters

• Stand-alone or component in automated substation control system

• Applicable for transformers with windings in a ring bus or breaker-and-a-half configuration

​

Key Benefits

​

• Percent restrained and unrestrained differential protection with inter-turn fault detection

• 2nd harmonic inrush inhibit and, and independent harmonic detection element

• TOC elements for backup protection

• Transducer I/Os (RTD & dcmA)

• FlexElements

• FlexCurves

​

Protection & Control

​

The T35 transformer protection system is a three-phase transformer relay designed to protect power transformers with up to six windings/restraints. The T35 provides for automatic or user-definable magnitude reference winding selection for CT ratio matching. The T35 performs automatic phase shift compensation for all types of transformer winding connections. The T35 algorithm allows the user to enable removal of the zero-sequence current even for delta-connected transformer windings, facilitating transformers with a variety of grounding configurations. As part of the Universal Relay (UR) Family, the T35 provides a cost-effective solution and superior protection and control.

​

Functional Block Diagram

​

​

​

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

​

​

Monitoring & Diagnostic

​

Key Features

​

• Metering - current, voltage, power, energy, frequency, temperature

• Oscillography – analog and digital parameters at 64 samples/cycle

• Event Recorder - 1024 time tagged events with 0.5ms scan of digital inputs

• Data Logger - 16 channels with sampling rate up to 1 sample/cycle

• Setting for security audit trails for tracking changes to T35 configurations

​

​

​

Monitoring & Diagnostic

​

The T35 includes high accuracy metering and recording for all AC signals. Voltage, current, and power metering are built into the relay as a standard feature. Current and voltage parameters are available as total RMS magnitude, and as fundamental frequency magnitude and angle.

​

​

​

​

Advanced Automation

​

The T35 incorporates advanced automation features including powerful FlexLogic™ programmable logic, communication, and SCADA capabilities that far surpass what is found in the average transformer relay. The T35 integrates seamlessly with other UR relays for complete system protection.

​

​

​

​

​

​

​

Communication

​

Key Features

​

Complete IEC 61850 Process Bus solution providing resource optimization and minimizing total P & C life cycle costs

• Three independent 100Mbps Ethernet ports enable purpose specific LAN support that eliminates latency effect of heavy traffic protocols on mission critical communication services

• Embedded IEEE 1588 time-synch protocol support eliminates dedicated IRIG-B wiring requirements for IEDs

• Direct I/O secures high-speed exchange of binary data between URs

• Increase network availability by reducing failover time to zero through IEC62439-3 PRP, HSR or dual HSR support

​

Advanced Communications

​

The T35 provides advanced communications technologies for remote data and engineering access, making it easy and flexible to use and integrate into new and existing infrastructures. Direct support for fiber optic Ethernet provides high-bandwidth communications allowing for low-latency controls and high-speed file transfers of relay fault and event record information. The available three independent and redundant Ethernet options provide the means to create fault tolerant communication architectures in an easy, cost-effective manner. 

The T35 supports the most popular industry standard protocols enabling easy, direct integration into DCS and SCADA systems.

​

• IEC 61850-9-2LE/IEC 61869 networked or IEC61850-9-2 Hardfiber process bus support

• DNP 3.0 (serial & TCP/IP)

• Ethernet Global Data (EGD)

• IEC 60870-5-103 and IEC 60870-5-104

• Modbus RTU, Modbus TCP/IP

• HTTP, TFTP, SFTP and MMS file transfer

• Redundant SNTP and IEEE 1588 for time synchronization

• PRP as per IEC 62439-3

• Supports Routable GOOSE (R-GOOSE)

​

Interoperability with Embedded IEC 61850

​

Use the T35 with integrated IEC 61850 to lower costs associated with power transformer protection, control and automation. GE’s leadership in IEC 61850 comes from thousands of installed devices and follows on years of development experience with UCA 2.0.

​

​

​

​

Software & Security

​

Cyber Security - CyberSentry™ UR (FW v7.4xx)

​

CyberSentry enables UR devices to deliver full cyber security features that help customers to comply with NERC CIP and NITIR 7628 cyber security requirements through supporting the following core features:

Secure FW upgrade

​

UR FW files v7.9 and up now include a hash code that allows for authentication prior to being used for upgrading UR devices.

​

Password Complexity

Supporting up to 20 alpha- numeric or special characters, UR passwords exceed NERC CIP requirements for password complexity. Individual passwords per role are available.

​

AAA Server Support (Radius)

Enables integration with centrally managed authentication and accounting of all user activities and uses modern industry best practices and standards that meet and exceed NERC CIP requirements for authentication and password management.

​

Role Based Access Control (RBAC)

Efficiently administrate users and roles within UR devices. The new and advanced access functions allow users to configure up to five roles for up to eight configurable users with independent passwords. The standard “Remote Authentication Dial In User Service” (Radius) is used for authentication. 

​

Event Recorder (Syslog for SEM)

Capture all cyber security related events within a SOE element (login, logout, invalid password attempts, remote/local access, user in session, settings change, FW update, etc), and then serve and classify data by security level using standard Syslog data format. This enables UR devices integration with established SEM (Security Event Management) systems.

​

EnerVista™ Software

​

The EnerVista™ suite is an industry-leading set of software programs that simplifies every aspect of using the T35 relay. The EnerVista™ suite provides all the tools to monitor the status of the protected asset, maintain the relay, and integrate information measured by the T35 into DCS or SCADA monitoring systems. Convenient COMTRADE and Sequence of Events viewers are an integral part of the UR setup software included with every UR relay, to carry out postmortem event analysis and ensure proper protection system operation.