ML19322B954
| ML19322B954 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 05/18/1967 |
| From: | Ferguson R US ATOMIC ENERGY COMMISSION (AEC) |
| To: | US ATOMIC ENERGY COMMISSION (AEC) |
| References | |
| NUDOCS 7912191040 | |
| Download: ML19322B954 (5) | |
Text
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UNITED STATES GOVERNMENT Memorandum To
- Files DATE: L'Y !
THRU:
on Ge case, Director, RS FRObi : R. L. Fergdson, Engineering & Components 3 ranch, RS tk. k 't 9 7
SUBJECT:
OCCIEE NUC'M STATION UNITS 1, 2 and 3 ELECTRICAL SYSTEMS - DOCKET NOS. 50-269; 270 and 2e7 J
To date, the electrical system,3f the Oconee Nuclear Station has been described in the PSAR, including amendments 1, 2 and 3 This description has been supplemented by meetind with Mr. C. '411e (Duke Power Co. ) on 7
May 8, 1967 The Oconee electrial system has been evaluated against the requirements of auxiliary electrical power systems for nuclear power plants presentel in the following documents:
1.
General Criteria Nos 24 and 39 2.
PWR Supplementary Criteria - Section 8 - kalliary Electrical Power System 3
Preliminary Guide for the evaluation of kuiliary Electrical Power System - Issue 2, October 6,1966 1
4.
IEEE Proposed Standard - A niliary Electrical Power System for D: clear Power Plants - March 15, 1967 This evaluation has been made to determine tne adequacy of both the subject system and presently documented requirements.
The subject electrical system ccmplies with the intent of the four documents listed above, subject to the following:
1.
The instrumentation, controls and protection system of the nydro turbines at Keovee and the gas turbines at Lee have not been presented in suffi-cient detail to permit an unqualified approval. The applicant has expressed his intent to lesign these systems such that the requirements for peaking sertice vill not interfere with the requirements for standby power service. However, these systems have not yet been developed in sufficient detail to assure this intent has been met.
2.
Special
- N strative controls have not yet teen developed for the following:
(1) The =aintenance of the 13 3 kv underground transmission line, the 23017 overhead transmission line from Keovee to Oconee.
E Buy U.S. Savings Bonds Regularly on the Payroll Savings Plan 3912191099
Files (2) The operation and maintenance of the gas turbines at the Lee plant and the 100 kv overhead line from the Lee plant to Oconee, when the Lee plant gas turbines are used as a standby source for Oconee.
One of the transmissicn lines frem the standby units for the nuclear station is an overhead transmissions line, therefore, abnormal weather conditions nay cause complete dependence on the single underground transmission line for electrical power. Also, the applicant proposes that one nuclear unit be ccncidered as a standby source for the other to further evaluate these two cases.
I have requested additional information from Mr. Wylie via telecen, May 12, 1967 His pre 14*e/ ansvers were received via telecon, May 16, 1967 1.
The number of attempts and number of failures of (a) Cutback of an on-line power plant from full power to 15%;
(b) Startup of hydro units on supervisory control; (c) Startup of gas turbines on supervisory control.
2.
Outage rates of underground and overhead cables.
The infor=ation presented in discussions with Mr. Wylie on May 8, 1967, is sumcarized below:
1.
Trans=ission Lines (a) All 230 kv lines allow power to flow either from the plant or to the plert.
(b) The 100 kv overhead line vill be continuously energized.
The 13 8 kv underground line vill be energized at anytime that at least one hydro unit is running. Therefore, the 13.8 kv underground line and 100 kv overhead line vill be continuously =onitored for auxiliary while they are energized.
2.
Keovee Hydro Station (a) Nomally used as peaking plant, expected to be operated for several hours each week day.
(b) Can pick up the safety feature load from black-start in 23 seconds.
4 (c) If tripped off line at full power due to system disturbance, it can pick up full load in 7 seconds. Tine is shorter if load at time of trip is less.
s Files -
(d) Any foreign =ateri 1 that can pass throu6h racks at water inlet ec= pass through the water Steel.
(e) Bearing cooling water is taken frcs separate inlet.
Unit can run without cooling vater for more than 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />.
(f) Hydro plant is started by opening vicket gates.
These are powered by hydraulic accumulators.
Stored hydraulic energy is sufficient for three full opening and closing cycles.
Battery power is required to control the hydraulic governer, to polarice the generator's field. There =ay be a problem in main-taining hydraulic power for governcr vnile chasing a system transient.
(See Northeast Blackout report.)
(g) Protection system on hydro plant will be limited to only those parsmeters that vill prevent generation of power, such as, generatcr insulation treakdown or loss of field.
3 Switching (a) Nor:::al switching of auxiliary pcVer from station generator to 230 kv lines will be 4 cycles.
(b) If sync-check ralaying prevents transfer, switchin6 vill occur when volta 6e decays to 25% (approx 1=ately 30 cycles).
(c) About 1 minute is required for the =ctor-driven switching of the 13 8 kv underground line frem one hydro 6enerator to another.
(d) Mr. 'Jylie did not kncy of any failure of a bus transfer at Duke Power Co.
4.
Instrunents and Controla (a) Cos::=unication line between Keevee and Oconee vill te separate from the power lines.
(b) I:etails of instruments, controls and protective system are not yet developed. All critical parameters of Keovee vill be alarmed in Oconee's tvc control rocms.
Scme infor=ation till be presented to the operr.tcr continuously and sc=e vill be available on donnM.
Control of the hydro units for standby pcwer vill be capable from either control roCn.
Files 5 Maintenance (a) Special administrative controls vill be required for the maintenance of the 13 8 kv underground line, the 230 kv overhead line from Keovee and the 100 hv overhead line from Lee.
(b) When the hydro plants are down for mainte-a"ce, a 30 mv gas turbine driven generator can be started and connected to Oconce via the 100 kv overhead line. The scheduled maintenance on the hydro units vill be done in good veather and at off peak times. Unscheduled maintenance was not discussed. The gas turbine Senerator units can accept a step load of all engineered safety features.
(c) Special *inistrative controls vill be required for the operation of the gas turbines at Lee as a Standby Pcver Source for Oconee.
6.
Standby Transformers (c) These vill be enerci cd and monitored continuously.
(b) They will be able to withstand a 50% overload for 15 minutes. They vill be provided with short circuit but not overload protection.
Therefore, such overloads vill not trip out the transformers.
Two specific require =cnts cf the guide documents are not net. They cre:
The nor=al power for the engineered safety features requires automatic bus transfer during an unscheduled plant shutdown, and, engineered safety feature loads are =1xed with nocessential loads on the same bus.
I believe these tvc requirenents should be valved for the application teccuse:
1.
When the standby power is from the hydro units via the 230 kv overhead line, all essentici and nonessential leads can be carried.
2.
When the standby power is from the hydro units or gas tu-bines at Lee via the 13 8 kv or 100 kv line, all connected loads on two or three essential buses can te car."_ed.
Attachment:
Ivaluation Sheet ec: Edson G. Cace, Oir., RS C. G. Lon6
- 7. A. Moore D. F. Sullivan 3.Gri=es R. L. Ferguson 4
EVALUATION W m "
OCONES NUCLEAR PCWER STATION DOCKET NT. 50-269, 270 AND 287 AUXILIARY ELECTRICAL POWER STATION Item Remarks Reliability Component quality Adequate Arrangement Single failure Component Protection Storms, lightning, vind, cnow or ice Adequate Floods Forest fires Earthquakes Accident forces Accident environment Capacity and Availability Nomal power cource Adequate Standby power source Protection, Instrumentation Intent appears adequate.
System and Controls is not described in sufficient detail to fully evaluate -indepen-dence of peaking and standby service requirements.
d Test Program Appears adequate, however, continuous monitoring aspects of the electrical system are not described.
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