APPLICATION NOTES
10. NEW ADDITIONAL FUNCTIONS – VERSION C5.X (MODEL 0360J) 282
1.2 MiCOM distance relay
MiCOM relays are a range of products from AREVA T&D. Using advanced numerical technology, MiCOM relays include devices designed for application to a wide range of power system plant such as motors, generators, feeders, overhead lines and cables.
Each relay is designed around a common hardware and software platform in order to achieve a high degree of commonality between products. One such product in the range is the series of distance relays. The relay series has been designed to cater for the protection of a wide range of overhead lines and underground cables from distribution to transmission voltage levels.
The relay also includes a comprehensive range of non-protection features to aid with power system diagnosis and fault analysis. All these features can be accessed remotely from one of the relays remote serial communications options.
P44x/EN AP/F65 Application Notes
Page 10/286 MiCOM P441/P442 & P444
1.2.1 Protection Features
The distance relays offer a comprehensive range of protection functions, for application to many overhead line and underground cable circuits. There are 3 separate models available, the P441, P442 and P444. The P442 and P444 models can provide single and three pole tripping. The P441 model provides three pole tripping only. The protection features of each model are summarised below:
• 21G/21P: Phase and earth fault distance protection, each with up to 5 independent zones of protection (6 zones from version C5.0, model 36J). Standard and customised signalling schemes are available to give fast fault clearance for the whole of the protected line or cable.
• 50/51: Instantaneous and time delayed overcurrent protection - Four elements are available, with independent directional control for the 1st and 2nd element. The 3rd element can be used for SOFT/TOR logic. The fourth element can be configured for stub bus protection in 1½ circuit breaker arrangements.
• 50N/51N: Instantaneous and time delayed neutral overcurrent protection. Two elements are available (four elements from version C1.0, model 020G or 020H).
• 67N: Directional earth fault protection (DEF) - This can be configured for channel aided protection, plus two elements are available for backup DEF.
• 32N: Maximum of Residual Power Protection - Zero sequence Power Protection This element provides protection for high resistance faults, eliminated without communication channel.
• 27: Undervoltage Protection - Two stage, configurable as either phase to phase or phase to neutral measuring. Stage 1 may be selected as either IDMT or DT and stage 2 is DT only.
• 49: (Since version C2.X) Thermal overload Protection - with dual time constant. This element provides separate alarm and trip thresholds.
• 59: Overvoltage Protection - Two stages, configurable as either phase to phase or phase to neutral measuring. Stage 1 may be selected as either IDMT or DT and stage 2 is DT only.
• 67/46: Directional or non-directional negative sequence overcurrent protection - This element can provide backup protection for many unbalanced fault conditions.
• 50/27: Switch on to fault (SOTF) protection - These settings enhance the protection applied for manual circuit breaker closure.
• 50/27:Trip on reclose (TOR) protection - These settings enhance the protection applied on autoreclosure of the circuit breaker.
• 78 – 68: Power swing blocking - Selective blocking of distance protection zones ensures stability during the power swings experienced on sub-transmission and transmission systems (stable swing or Out of Step condition = loss of synchronism).
From version C1.0, the relay can differentiate between a stable power swing and a loss of synchronism (out of steps).
• VTS: Voltage transformer supervision (VTS). - To detect VT fuse failures. This prevents maloperation of voltage dependent protection on AC voltage input failure.
• CTS: Current transformer supervision - To raise an alarm should one or more of the connections from the phase CTs become faulty.
• 46 BC: Broken conductor detection - To detect network faults such as open circuits, where a conductor may be broken but not in contact with another conductor or the earth.
• 50 BF: Circuit breaker failure protection - Generally set to backtrip upstream circuit breakers, should the circuit breaker at the protected terminal fail to trip. Two stages are provided.
Application Notes P44x/EN AP/F65
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1.2.2 Non-Protection Features
The P441, P442 and P444 relays have the following non-protection features:
• 79/25: Autoreclosure with Check synchronism - This permits up to 4 reclose shots, with voltage synchronism, differential voltage, live line/dead bus, and dead bus/live line interlocking available. Check synchronism is optional.
• Measurements - Selected measurement values polled at the line/cable terminal, available for display on the relay or accessed from the serial communications facility.
• Fault/Event/Disturbance Records - Available from the serial communications or on the relay display (fault and event records only).
• Distance to fault locator - Reading in km, miles or % of line length.
• Four Setting Groups - Independent setting groups to cater for alternative power system arrangements or customer specific applications.
• Remote Serial Communications - To allow remote access to the relays. The following communications protocols are supported: Courier, MODBUS, IEC60870-5/103 and DNP3 (UCA2 soon available).
• Continuous Self Monitoring - Power on diagnostics and self checking routines to provide maximum relay reliability and availability.
• Circuit Breaker State Monitoring - Provides indication of any discrepancy between circuit breaker auxiliary contacts.
• Circuit Breaker Control - Opening and closing of the circuit breaker can be achieved either locally via the user interface / opto inputs, or remotely via serial communications.
• Circuit Breaker Condition Monitoring - Provides records / alarm outputs regarding the number of CB operations, sum of the interrupted current and the breaker operating time.
• Commissioning Test Facilities.
1.2.3 Additional Features for the P441 Relay Model
• 8 Logic Inputs - For monitoring of the circuit breaker and other plant status.
• 14 Output relay contacts - For tripping, alarming, status indication and remote control.
1.2.4 Additional Features for the P442 Relay Model
• Single pole tripping and autoreclose.
• Real Time Clock Synchronisation - Time synchronisation is possible from the relay IRIG-B input. (IRIG-B must be specified as an option at time of order).
• Fibre optic converter for IEC60870-5/103 communication (optional).
• Second rear port in COURIER Protocol (KBus/RS232/RS485)
• 16 Logic Inputs - For monitoring of the circuit breaker and other plant status.
• 21 Output relay contacts - For tripping, alarming, status indication and remote control.
P44x/EN AP/F65 Application Notes
Page 12/286 MiCOM P441/P442 & P444
1.2.5 Additional Features for the P444 Relay Model
• Single pole tripping and autoreclose.
• Real Time Clock Synchronisation - Time synchronisation is possible from the relay IRIG-B input. (IRIG-B must be specified as an option at time of order).
• Fibre optic converter for IEC60870-5/103 communication (optional).
• Second rear port in COURIER Protocol (KBus/RS232/RS485)
• 24 Logic Inputs - For monitoring of the circuit breaker and other plant status.
• 32 Output relay contacts - For tripping, alarming, status indication and remote control.
1.3 Remark
The PSL screen copy extracted from S1, uses the different types of model P44x (07, 09…).
(See the DDB equivalent table with the different model number).
Example: check synch OK (model 07) = DDB204 check synch OK (model 09) = DDB236
• It is recommended to check in the DDB table, the reference number of each cell, included in the chapter P44x/EN GC/E33 (“Relay menu Data base”)
• Version C2.x uses the model 030 G / 030 H / 030 J
Application Notes P44x/EN AP/F65
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