Relays are compact devices that are connected throughout the power system to detect intolerable or unwanted conditions within an assigned area. Presently there are options of more than one technology providing relays for the same application. Some of them are very relevant whereas few are not the right choice.
We are dealing with AREVA make relays both Numerical and electromechanical. We can also change existing electromechanical realys to Numerical relay with a minimum shut down period keeping the diamension of the panel same.
Technically, most relays are small systems within themselves.Protective relays or systems are not required to function during normal power system operation, but must be mediately available to handle intolerable system conditions and avoid serious outages and damage. Thus, the true operating life of these relays can be on the order of a few seconds, even though they are connected in a system for many years. In practice, the relays operate far more during testing and maintenance than in response to adverse service conditions.
Nonetheless, protective relaying is a highly specialized technology requiring an indepth understanding of the power system as a whole. Modern relaying systems are highly reliable and provide accurate protection .
The decision to select a right technology is becoming increasingly evident nowadays. Electromechanical relays are still a very popular choice when it comes to providing simple protection requirement and there is no plans of going in for communication systems.
Pl contact us before selecting any kind of relays of AREVA make
As explained above Numerical relays with communication facility is far superior to any other relay without communication facility. Relays without communication hence can not be claimed as numerical relay.
Numerical technology implies sampling of the relay inputs, then A→D conversion into number format. These numbers are then used by mathematical algorithms, which generate the relay operating characteristics. Numerical relays are strongly dependent on algorithm (software statements) for its operation and due to extremely powerful processor, relays can perform variety of complex protection function.
The MICOM P111 relays are suitable for all the application where over current and/or earth-fault protection are required. Thanks to its favorable"price vs technical features" ratio, P111 can because both in medium voltage and in low voltage applications (specifically where communication facilities are required)
MiCOM P9xx voltage and frequency management relays provide an integrated solution for secure and efficient operation of the power system.Their versatility of application and the association of protection functions with automation, control and measurement functions, provide an optimal and innovative solution for ensuring power system stability, as well as maintenance reduction.The enhanced techniques employed, designed to operate under non-linear abnormalities and sub oscillations, eliminate the risk of unwanted operation.
MiCOM P145 feeder management relay provides an integrated solution for the complete protection,control and monitoring of overhead lines and underground cables from distribution to transmission voltage levels.With a wide range of protection functions and relay flexibility, it is suitable for application on varied network requirements from solidly grounded systems to the more specialized Petersen coil grounded system requirements.A customizable user interface and programmable graphical scheme logic provides simple and flexible application. The integrated user function keys and tri-color programmable LEDS provide a cost effective solution for full feeder scheme applications.
Stability and thermal limits, voltage collapse and loop flows are usual constraints that system planners and operators have to deal with. With today’s stretched systems with minimal reserve, cascading events such as the loss of generator units or transmission lines, can easily lead to severe power swings, voltage collapses,possible loss of synchronize and under frequency load shedding. Use the advanced phosphor measurement unit as part of a wide area monitoring and control system, to assess key metrics in or between critical areas in the power system. High Speed data transfers of key system parameters complemented with advanced visualization tools at the Control Centre, enhances the system operator decision capability. Anticipate impending system failures such as angular instability by monitoring bus angles between key generating areas. Monitor impending voltage instability problems by monitoring high VAR flows in the network associated with fast declines in voltage magnitudes in areas.