SCADA Delivers Rapid Response
Control and Data Acquisition
System, is used by ESB Networks
to monitor and control over 100
substations, both at 38kV and
100kV level. The primary role of the
system is rapid response to fault
isolation and restoration of supply
to customers. Faults and unsafe
conditions can be isolated and
supply may be restored through
alternative routing within a matter
of minutes.
The system plays a crucial role
in assisting Network Technicians
in fault hunting and isolation by
providing details of the type of
fault, outlet and network
presectionalising. It is also linked
into the Operations Management
System (OMS), which provides
outage and restoration times
information to the Customer Call
Centre.
How does SCADA work?
The SCADA system requires data
to be collected from substation
equipment and its transmission
over a telecommunications circuit
to computers in Wilton and
Leopardstown Distribution
Control Centres (DCC). The
computers analyse and translate
the data received into an on-screen
visual representation of the
substations, enabling the Control
Room Operators in the
Distribution Control Centres to
interpret and make operational
decisions. This may require direct
operation of equipment or the
dispatch of Network Technicians
to investigate the fault and carry
out repairs.
The two Distribution Control
Centres provide 24/7 monitoring,
operation and control of the 110kV
and 38kV networks assigned to
them. Leopardstown DCC controls
and operates substations north of a
line from Dublin to Castlebar.
Wilton DCC is responsible for the
balance of the networks south of
this line. Apart from
communications with Supervisors
and Network Technicians involved
in the control and operation of the
medium voltage networks, over
125,000 operation instructions are
issued every year from the DCC's
directly to plant and equipment in
these stations
Telecommunications
Infrastructure
The telecommunications
infrastructure is a key component
of the SCADA system. It must be
reliable, secure and enable control
and monitoring data to be passed
to and from substations to the
DCC's. The geographical location
of each substation and the local
communications system in general
dictate the type and mix of
communications media used. The
media used includes poling radio,
private wire, fibre optic and pilot
cables. Communication via
satellite is also being used for a
number of substations and
windfarms where the provision of
poling radio or landlines is too
expensive.
VHF Poling radio is the most
common type used by ESB
Networks. The SCADA data is
transmitted to and from the
station via 'Hi-Sites' which then
relay the signals to the Control
Centres via the internal ESB
microwave network.
SCADA has many benefits
including:
- Immediate access to power system status.
- Fast and easy monitoring of power system security .
- Direct preventive actions and restoration even during disturbance situations.
- Extensive reporting and archiving capabilities including export and restoration of archived data.
- Information for post-fault analysis.
