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Critical Need for Communications Protection in a Deregulated Power Market. 1999 IEEE/PES Ernest M. Duckworth Jr., P.E., Senior Member IEEE & John S. Duckworth, P.E. Introduction. A very effective power system operation alone will not be enough as we move into the 21st Century
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Critical Need for Communications Protection in a Deregulated Power Market 1999 IEEE/PES Ernest M. Duckworth Jr., P.E., Senior Member IEEE & John S. Duckworth, P.E.
Introduction A very effective power system operation alone will not be enough as we move into the 21st Century In a deregulated power market, the successful power company will have a very reliable wire-line communication network when fiber is not cost effective. The single most important key to success in this new age will be our ability to communicate error free and without interruption over wire-line, which still represents a large majority of the present entrance facilities.
Reliable Wire-Line CommunicationInto High Voltage Locations • Follow ANSI/IEEE Std. 487-1992 • Know the fault characteristics, grid resistance, X/R ratio, etc. • Cooperate and coordinate the protection of leased lines • Practice Personnel Safety • Go to Training
Definitions& acronyms used in Electrical Protection • High Voltage Interface (HVI) > The separation of wire-line communications conducting paths with the use of magnetic or optical isolation • Ground Potential Rise (GPR) > A voltage that develops on a grounding system from current flowing through the impedance of that ground • Ground Grid or Ground Mat > The grounding system built under a substation or power plant in which all metallic equipment and plant are bonded • Remote Ground > The distant end of a communications circuit that is at a different ground reference point with respect to the near end
Why do High Voltage Locations Require Isolation? • Ground Potential Rise (GPR)-Average of one per 100 miles of power cable plant • Standard Gas Tube, MOV, SAD, Carbon Block, or any other shunting device does not work • High Voltage Interface (HVI) must be a part of the Facility Entrance • Personnel Safety & Equipment Protection cannot be obtained without an HVI
When is an HVI Required? • GPR exceeds 1000V-Peak-Asymmetrical • Regardless of the GPR if circuit reliability (Class A Service) is a requirement • Ultimately when the responsible design Engineer perceives its placement as necessary for the protection of personnel and equipment
Where is an HVI Physically Located? • Within the boundary of the ground grid or ground mat • Where the station cables will have the shortest lengths • Where it can be maintained properly and sheltered from the elements
How is an HVI Placed? • Follow IEEE Std. 487-1992, Guide for the Protection of Wire-Line Communication Facilities Serving Electric Power Stations • Conceptually visualize the HVI as having two sides • High Voltage Side is the hot side or front side and it connects to wire-line pairs that leave the high voltage location (HVL). Must be in nonmetallic (PVC) conduit with floating shield • Low Voltage Side is the cold side or back side and it connects to wire-line pairs that must stay within the HVL. Must be in metallic (steel) conduit with shield grounded • Never place hot side pairs closer than 5 inches from any ground • Never place cold side pairs closer than 5 inches from hot side pairs • Never work on an HVI without standing on an 18kV rubber blanket and wearing rubber gloves
Conclusions • The three examples listed in the paper were actual cases of lost revenue from not isolating wire-line communications services • In a deregulated power market, costs will be the control like never before and the loss of communications will mean disaster • Don’t gamble with the possible loss of real time information by not properly isolating your wire-line communications. It is just not worth it • Electric Companies properly utilizing isolation equipment on their wire-line communication facilities will be prepared to compete head-on in the new age of a deregulated power market • Are you ready now? Are you trained? Do you have the right tools? • A good number are and do! • A good number aren’t and don’t! Which one are you?
References, Training & ToolsinMastering Electrical Protection • IEEE Std. 487, IEEE Std. 367, U S WEST Reference Publication “Special High Voltage Protection” #77321,June 1998, and Bell Practice 876-310-100 • Protection Technologies Inc training in Electrical Protection by William (Bill) Petersen. Two day engineering and installation seminars. Call 801-561-5464 • Web Site: http://gpr-expert.com • Expert system software: GPR-Expert by Expert Systems Inc., 703-440-1455 • Richard Knight-Engineering Manager Positron Industries, 505-298-5400, Lewis (Lew) Stone-Technical Specialist, 303-871-8656
THANKS FOR BEING HERETODAY Ernest M. Duckworth Jr., P.E. VP-Power Products Division Positron Industries Inc. 962 Coronado Drive Sedalia, CO 80135 PH: 303-688-5800 Fax: 303-688-5551 duckyern@email.msn.com John S. Duckworth, P.E., CEO Expert Systems Programs and Consulting (703) 440-1455 jack@gpr-expert.com