Overview

The E9-GEN is a dedicated generator or generator-transformer block protection and control IED; the relay provides complex protection, control and monitoring functions for generator/step-up transformer blocks. It is a member of the DGEN (former product type: DTRV) product type in the EuroProt+ product family. The EuroProt+ family complex protection in respect of hardware and software is a modular device. Because of the modular architecture, the modules are assembled and configured according to the user’s requirements; from that point on, the software determines the functions.

The DGEN (former product type: DTRV) type is especially designed for protection and control applications of power transformers and generators including generator-transformer blocks. Additionally the DGEN (former product type: DTRV) product type includes variety of versatile protection functions to meet the user’s the most demanding requirements.

Application

The E9-GEN is designed to be the main protection and control IED for synchronous power generators or entire generator blocks including the step-up transformer. The relay is member of the DGEN (former product type: DTRV) product type in the EuroProt+ product family.

The E9-GEN relay includes variety of versatile protection functions along with the main differential protection, such as overcurrent, over-/undervoltage, frequency protections. The device contains several functions especially made for generator applications as well, e.g. thermal-based negative sequence overcurrent protection, voltage dependent overcurrent, inadvertent energizing protections, loss of excitation, 100% stator earth fault protection, rotor earth fault protection etc. It can be applied as a back-up protection relay for downstream equipment (e.g. feeders, cables etc.).

The E9-GEN generator(block) protection relay can support the double breaker terminals such as breaker and a half, or ring bus topologies. Synchro-check is also available.

The IED includes wide range of control and supervisory functions which provide full control and user defined interlocking schemes for the primary switchgear at the substation.

THE SCOPE OF APPLICATION

• Generator differential protection or block differential protection with two ends
• In case of block differential protection:
• Automatic phase shift and turns ratio compensation of the step-up transformer
• 2nd and 5th harmonics restraint for transformer inrush and overexcitation detection
• Protections specifically made for generator applications
• Voltage dependent overcurrent protections
• Interturn fault protection for larger generators (current or voltage based, depending on the winding)
• Loss of excitation protection
• Pole slipping (out-of-step) protection
• Rotor earth fault protection for isolated/ungrounded or middle-grounded rotors
• Different kinds of 95% earth fault protections:
• Residual overcurrent (can be sensitive depending on the CT)
• Residual overvoltage
• Restricted earth fault
• 100% Stator earth fault protections:
• 3rd harmonic undervoltage
• 3rd harmonic differential overvoltage by measuring the residual voltage in the neutral and the terminal point (two operation modes if generator CB is present)
• Restricted earth-fault protection
• The implemented protection functions provide back-up protection for downstream equipment (e.g. feeders, cables etc.).
• Independent trip logic and circuit supervision for each trip circuit (circuit breaker, excitation, turbine valve etc.)
• Support for the double breaker terminals such as breaker and a half, or ring bus topologies
• Supervision of current and voltage transformers
• Programmable interlocking schemes
• Optional external unit:
• Remote I/O unit (RIO)
• Optional transducer I/Os (RTD/mA)

Protection & control functions

The E9-GEN configuration measures three phase currents from both sides of the generator (or the neutral side of the generator and the HV side of the step-up transformer), the residual current(s), three phase voltages of the generator, residual voltage(s). The main protection functions are the generator (block) differential protection, overcurrent, voltage dependent overcurrent, frequency, loss of excitation and earth-fault protection functions. The additional protection functions are available to provide the necessary complexity according to the generator´s protection needs as well as back-up protections for downstream equipment (e.g. feeders, cables etc.). 

Documentation