The demands from external
stakeholders for greater
transmission system
reliability are growing louder. Regulatory agencies and Congress are now pushing for significant
additional investment in infrastructure, especially
transformative technologies that will make the national network of
transmission lines smarter, more robust and secure. Many of these
ideas for improved reliability are captured by the term 'smart grid'.
As a major
supplier of transmission switches, we have observed first hand the rapidly
growing interest and need for more intelligent sectionalizing. In
response to that interest, SEECO made the decision in 1995 to begin
development of a suite of new products that would complement and support
the automation of transmission switches. Particular emphasis was
placed on products that would facilitate the rapid identification and
isolation of faults and the restoration of service. Today,
SEECO is the industry leader in transmission sectionalizing
automation. No other company has the resume of successful
installs, the breadth of project experience or the integrated suite of products
necessary to deliver successful transmission automation.
SEECO partners with many
utilities to deliver automation solutions specific to their own unique
automation objectives. Solutions are always customer and application
specific. Several automation applications that we have found to be
common to many utilities include:
Distributed Control
(Independent, Automatic Sectionalizing)
The above list is not exclusive
and many other applications are possible. If you do not see your
application in the above list, please contact SEECO to discuss your
specific automation objectives.
The operational and financial
benefits of investing in transmission automation can be significant, and may include one or more
of the following depending on your
specific application:
Reduced outage
duration - problem isolation and service restoration can be accomplished
in seconds rather than hours or days
Cost effective -
payback on capital investment can be as fast as a single incident
Rapid
implementation - a 'solution' installed in weeks, not months
Brand independent
- can be applied to any brand or configuration of group operated switch
without limitation
Seamless integration - a complete
automation solution from a single source that eliminates compatibility and
coordination issues caused by sourcing from multiple suppliers
Secure - where
control of the switch is independent and automatic (distributed control), the
local control system cannot be compromised or
hacked; distributed control is not dependent on IT, communication or network resources.
SEECO's automation products can be
easily integrated into any existing supervisory control system or operated
stand alone (distributed control), providing independent automatic operation of switches under a
range of customer defined 'event' or threshold parameters. SEECO
automation products include the following devices:
Transmission class
motor operators - The most basic building block for transmission
automation, this device will operate any brand or configuration of group
operated switch and will fit seamless into any supervisory control system
for remote operation and control. Operators can be supplied with or
without a customer specified RTU and communication device.
For applications
where real time line information is required by supervisory control
systems and personnel or where control of the switch is distributed for
independent automatic sectionalizing, the following devices can be
supplied along with the motor operator for a complete automation package:
Current and
voltage sensors - Monitoring insulators which interrogate the line and
generate real time current and voltage wave forms (output signals).
For supervisory control systems, the output information can be transmitted
as RMS values through an RTU.
For distributed control of the switch, the current and voltage output
signals are used by a local control logic device that processes the information
and acts to open or close the switch.
Local control
devices - SEECO's CVD and ASB
control logic devices provide local processing of output signals from line
sensors or traditional oil-filled instrument transformers.
These devices compare real time current and/or voltage output signals to
stored 'threshold' parameters to determine if an 'event' has occurred.
Depending on your application, an event can be fault current of a
specified amplitude and duration, continuous gain or loss of potential for
a specified time, a combination of the above or other conditions.
Local processing
of line sensor output signals enables substantially faster recognition of
an event because raw analog data streams do not have to be transmitted to
a central SCADA processor. Indication is near-instantaneous with the
event because only the event status is transmitted.
For supervisory
control applications, the local control logic device provides dry contact
indication through an RTU that a valid event has occurred. Operation
and control of the associated switch remains with the supervisory control
system.
For distributed
control applications, the device will open and/or close one or more
switches automatically upon recognition of an event. Individual
switches may be opened and closed multiple times (if so configured) to
effect the required sectionalizing result. If an RTU is present, the
device will also provide dry contact indication of the event, lock out
status of the switch and phase identity.
Remote
input/output module - SEECO's IOM communication device transmits status and control
signals between logically paired IED devices using RF, optical fiber or
RS485. In transmission automation applications, the IOM facilitates
the coordination of multiple switches within a given geographical area.
For distributed
control applications, switch open/closed status and line potential status
at various sectionalizing points are transmitted to a single (master)
local control logic device, which coordinates the operation at each point.
For supervisory control
applications, the IOM is used to transmit status and control signals between multiple
sectionalizing points and a single RTU and communication device; operation
and control of all sectionalizing switches is initiated only by the
supervisory control system through the single RTU. The use of less expensive remote I/O
devices eliminates the need for more costly RTU and communication devices
at each sectionalizing point.
More Information
For more detailed information on
SEECO automation products, please use the following hyperlinks to view the
appropriate product pages:
