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Protection Relays

MiCOM P54x
Differential Protection

With comprehensive distance and aided

DEF protection.
Design evolution K
Schneider Electric announces a major
evolution, with the P54x line differential
protection now incorporating the proven
technology of the sub-cycle distance
MiCOM P443, merged as one single Intelligent
Electronic Device (IED).

Customer Benefits
The new P54x evolution combines current
differential, five zone sub-cycle distance
• Reduced spares holding
protection and a phase segregated aided
• Harmonized scheme drawings
directional earth fault protection, providing the
and panels wiring
complete solution for any type of fault on the
• Minimum training requirements
power system.
• Reduced time to commission
This relay becomes the standard in all HV, EHV
and UHV line protection applications, duplicated
where dual redundant main protection is
demanded.
The enhanced functionality and versatility of
The P54x is the ideal working in either a two or three ended scheme,
cost-benefit choice to combined with the ease of adaptation as the
protect HV, EHV and power and communication systems expand and
change in complexity, make the P54x a truly
UHV lines or cables.
future-proof relay.
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Protection Relays MiCOM P54x

New features • GPS synchronizing caters for differences between

the transmit and receive path message routing,
• The evolution of P54x relays provides an excellent
as typically found in SONET (synchronous digital
cost-effective solution for line protection. The optional
hierarchy) multiplexed applications. The proven“ping-
five zones of sub-cycle distance protection can work
pong” time alignment method, and optional GPS
as independent parallel protection to the differential.
synchronism using the P594 for the common time
Alternatively, each zone can be set to work as
base, are carried forward into all new P543-P546
backup in case of communication failure.
models.
• Phase segregated aided directional earth fault DEF
• The new P54x relays deliver a comprehensive
(67N) can also be configured as main protection to
implementation of IEC61850, the international
provide high resistance ground fault detection.
standard for Ethernet-based communication in
The innovative “Virtual Current Polarizing” feature
substations. IEC61850 enables integration of all
even ensures correct operation when the fault
protection, control, measurement and monitoring
generates negligible zero or negative sequence
functions within a substation.
voltages.
The IEC61850 implementation in MiCOM relays
• The relay provides two independent tele-protection allows interoperability with other vendors’ IEDs
schemes each using a separate communication and systems, and easy integration with the PACiS
channel. The distance and DEF functions are substation control systems.
therefore flexible in configuration, to operate in
• P543 and P545 now facilitate in-zone transformer
shared channel logic or in discrete modes.
feeder applications
If differential protection is not used, ON-OFF
• All models support ABC and ACB phase rotation
teleprotection can be enhanced by using
• A new easy to use Human Machine Interface (HMI)
InterMiCOM64 digital signaling.
includes ten Programmable User Function Keys
• Differential current transformer supervision provides with associated Tri-Color LEDs. Typical control,
stability of the differential protection in case of failure maintenance, and commissioning options are
on any CT wire in the differential zone. The relay initiated from simple key presses, rather than the
will detect which one of the local or remote current need to navigate a menu.
transformers has failed, making it easy for the user to
identify the affected CT circuit.
Zone 3

Zone P (fwd)

Zone 2
Ia Ib Zone 1
Differential
current
| I diff | Directional
Ic (forward)
Zone P
(Reverse)
Trip
Zone 4
Percentage
bias k2 Offset Reverse Z3
Percentage
bias k1
Restrain Quadrilateral characteristics
I S1

I S2 Bias current
| I bias |
| I diff | = | I a + I b + I c | Zone 3
(without offset)

| I bias | = 0.5 ( |I a| + | I b| + | I c |) Zone 2

Zone 3
Zone P (reverse offset)
The relay operates when Directional
(reverse) Zone 1

I bias < I S2
© 2010 Schneider Electric - All rights reserved

(1) For
I diff > k1 I bias + I S1
Directional
(2) For I bias > I S2 (forward)

I diff > k2 I bias – (k2 – k1) I S2 + I S1

Zone P
(reverse)

Biased current differential protection

Zone 4

MiCOM characteristics

Schneider Electric 35 rue Joseph Monier CS30323 92506 Rueil-Malmaison Cedex, France Tel: +33 (0) 1 41 29 70 00 Fax: +33 (0) 1 46 99 71 00 www.schneider-electric.com

EnergyAutomation-DS-P54D-1317-EN 10-2010