L-2017-074, Redacted - St. Lucie, Unit 1, Updated Final Safety Analysis Report, Amendment No. 28, Chapter 8, Electric Power
Text
ELECTRIC POWER CHAPTER 8 LIST OF FIGURES FIGURE TITLE 8.1-1 State of Florida Electric System Map 8.2-1 Indian River Transmission Line Crossing Plan and Profile 8.2-2 Switchyard One Line Diagram 8.2-3a 2014 Grid Stability Analysis Case 1 8.2-3b 2014 Grid Stability Analysis Case 1 8.2-4a & 4b 2014 Grid Stability Analysis Case 2 8.2-5a & 5b 2014 Grid Stability Analysis Case 3 8.2-6a & 6b 2014 Grid Stability Analysis Case 4 8.2-7a & 7b 2014 Grid Stability Analysis Case 5 8.2-8a & 8b 2014 Grid Stability Analysis Case 6 8.2-9a & 9b 2014 Grid Stability Analysis Case 7 8.2-10a & 10b 2014 Grid Stability Analysis Case 8 8.3-1 Main One Line Wiring Diagram 8.3-1a Combined Main & Auxiliary One Line Diagram 8.3-2 Auxiliary One Line Diagram 8.3-3a 480V Misc., 125 V DC and Vital AC One Line Diagram Sheet 1 8.3-3b 480V Misc., 125 V DC and Vital AC One Line Diagram Sheet 2 8.3-4 Emergency Diesel Generator 1A/1B Load List 8.3-5 Typical Diesel Generator Automatic Starting Logic 8.3-6a Schematic Diagram Diesel Generator 1A - Start Circuit 8.3-6a1 Schematic Diagram Diesel - Generator 1A Start Solenoid 8.3-6b Schematic Diagram Diesel Generator 1A - Lock out Relay 8.3-6c Schematic Diagram Diesel Generator 1A Breaker 8.3-6d Schematic Diagram Diesel Generator 1B - Start Circuit 8.3-6d1 Schematic Diagram Diesel Generator 1B - Start CKTS 8.3-6e Schematic Diagram Diesel Generator 1B Lockout Relay 8.3-6f Schematic Diagram Diesel Generator 1B Breaker 8.3-6g Schematic Diagram 4160 V SWGR 1A3 Load Shedding Relays
UNIT 1 8-iv Amendment No. 27 (04/15)
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8.2.2.3 Transient Stability The transient stability study for 1975 was carried out to study system results for the following contingencies:
Case I Loss of largest supply to the grid (loss of St. Lucie Unit #1, 820 mw).
Case II Removal of the largest load from the grid (loss of Ringling load, 645 MW).
In response to the 1996 UFSAR review project and recommendations of various NRC Information Notices, a dynamic stability analysis was performed in 1998 (see PSL-ENG-SENS-98-056). This analysis assessed the response of the transmission system to the loss of the largest generator, the loss of largest load and the loss of most critical transmission circuit. The 1998 analysis has been updated with information for 2014; this analysis is summarized below.
PROCEDURE:
Contingencies were selected to conform with the USNRC Standard Review Plan (SRP), Section 8.2.III.1.f. Several cases were analyzed for each of the single event outages specified in the SRP. The most up to date transmission model representin g the 2014 summer peak load conditions was used. Additional non-firm transfers were modeled in the 2014 summer peak load case to bring the total Florida import level up to the transfer limit of 3700 MW. This represents the most conservative scenario.
The Power Technologies Inc. (PTI) dynamic simulation software (PSS/E, Rev. 32) was used to simulate the outage events. The simulation results were analyzed for any signs of instability, protective relay action or load shedding. The figures accompanying the simulation results, Figures
8.2-3a through 8.2-10b for cases 1 through 8 respectively, show the St. Lucie and FPL transmission system response to the contingency events modeled. Each Case figure is divided into parts which show voltage magnitude, machine angle, bus frequency and line flows.
Power flow analysis of the post transient condition for each case was done using the PTI load flow program (PSS/E, Rev. 32
). This analysis was used to assess whether the event causes any voltage or line loading violations.
ANALYSIS RESULTS:
Loss of the Largest St. Lucie Unit Load Case 1: The largest local power source within the Florida Interconnected power system is the St. Lucie #2 generator, which is modeled with a gross output of 1052 MW. The sudden trip of St. Lucie #2 is modeled in case 1. A St. Lucie #2 auxiliary load of 50 MW and 31 MVAR is left connected to the St. Lucie 230 kV bus.
System response is stable and no voltage or thermal limits are reached. Post-contingency voltage at the St. Lucie switchyard is 240.6 kV. The frequency briefly dips to 59.92 Hz and settles at 59.99 hertz. This response is consistent with observed response of the grid. The decline in machine angles is due to the slight decline in overall grid frequency. Machine angles are calculated relative to a fixed 60 hertz source with this simulation software. No transmission overloads, generator reactive overloads or voltage problems are caused by this
outage. Case 2: St. Lucie #2 is assumed to be off line with its capacity replaced by increased generation at the Martin, Manatee and Sanford power plants. The sudden trip of St. Lucie #1 (1032 MW) is modeled in case 2. A total St. Lucie auxiliary load of 100 MW and 62 MVAR is left connected to the St. Lucie 230 kV bus.
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System response is stable and no voltage or thermal limits are reached. The St. Lucie 230 kV bus voltage drops from 104.2% (of 230 kV) to 10 3.5% (231.8 kV). The frequency briefly dips to 59.94 Hz and settles at 59.99 Hz. This response is consistent with observed response of the grid. No transmission overloads, generator reactive overloads or voltage problems are caused by this event.
Loss of the Most Critical Transmission Circuit Case 3: One of the St. Lucie-Midway 230 kV lines are faulted and tripped in case 3. A three phase fault at the St. Lucie end of this circuit is disconnected after a total fault duration of 0.067 seconds (normal fault clearing time). The same system response would occur for an outage of the other circuits as the St. Lucie-Midway 230 kV circuits have nearly identical impedances.
System response is stable and no voltage or thermal limits are reached. Post-contingency voltage at the St. Lucie Switchyard is 240.0 kV. The loads for the remaining lines are well within their 1111 MVA ratings. No transmission overloads, generator reactive overloads or voltage problems are caused by this outag
- e.
Case 4: The Midway 500/230 kV autotransformer is faulted and tripped in case 4. A three phase fault on the 230 kV side is disconnected after a total fault duration of 0.067 seconds (normal fault clearing time). The Midway 500/230 autotransformer could be regarded as the most critical transmission circuit affecting the St. Lucie Plant.
System response is stable and no voltage or thermal limits are reached. Post-contingency voltage at the St. Lucie Switchyard is 238.2 kV. No transmission overloads, generator reactive overloads or voltage problems are caused by this outage.
Case 5: The Duval-Thalmann 500 kV circuit is faulted and tripped in case 5. A three phase fault is modeled on the Duval side. The fault is disconnected after a total fault duration of 0
.0 67 seconds (normal fault clearing time). The Duval-Thalmann 500 kV circuit could be regarded as the most critical transmission circuit affecting the Florida transmission system as this contingency frequently sets the Georgia to Florida transfer limit.
System response is stable and no voltage or thermal limits are reached. Post-contingency voltage at the St. Lucie Switchyard is 240.5 kV. No transmission overloads, generator reactive overloads or voltage problems are caused by this outage.
Loss of the Largest Transmission System Load Case 6: The Midway-Ranch 230 kV circuit is faulted and tripped in case 6, which causes the loss of a total of 210 MW of load. Although not the largest FPL system load loss following a single contingency, it is the largest load loss, for a single-contingency event, with the greatest impact on the St. Lucie Plant.
The System response is stable and no voltage or thermal limits are reached. Post-contingency voltage at the St. Lucie Switchyard is 240.9 kV.
UNIT 1 8.2-6 Amendment No. 27 (04/15)
Case 7: The Nobhill station is isolated by tripping the Andytown-Nobhill and Conservation-Nobhill 230 kV circuits.
This disconnects five distribution stations with a total load of 3 34 MW. This is the largest amount of load which can be interrupted by the outage of a single transmission system element.
System response is stable and no voltage or thermal limits are reached. Post-contingency voltage at the St. Lucie Switchyard is 241.0 kV. No t ransmission overloads, generator reactive overloads or voltage problems are caused by this outage.
Loss of the Largest Single FPL System Generation Unit Case 8: The largest power source within the Florida interconnected power systems is the Sanford combined-cycle Unit 5. The loss of Sanford Unit 5 represents a total loss of 1063 MW of generation capacity.
The System response is stable and no voltage or thermal limits are reached. Post-contingency voltage at the St. Lucie Switchyard is 240.2 kV.
CONCLUSION:
The transmission system and St. Lucie response is stable for all of the contingency events simulated.
None of the outage events modeled cause transmission voltage or line loadings to exceed ratings.
8.2.2.4 Response to Generic Letter 2006-02 Generic Letter (GL) 2006-02, "Grid Reliability and the Impact on Plant Risk and the Operability of Offsite Power," was issued to determine if compliance is being maintained with NRC requirements governing electric power sources and associated personnel training. The GL requested information in four areas: (1) use of protocols between the nuclear power plant (NPP) and the transmission system operator (TSO), independent system operator (ISO), or reliability coordinator/authority (RC/RA) and the use of transmission load flow analysis tools (analysis tools) by TSOs to assist NPPs in monitoring grid conditions to determine the operability of offsite power systems under plant technical specifications (TSs); (2) use of NPP/TSO protocols and analysis tools by TSOs to assist NPPs in monitoring grid conditions for consideration in maintenance risk assessments; (3) offsite power restoration procedures in accordance with Section 2 of NRC Regulatory Guide (RG) 1.155, "Station Blackout;" and (4) losses of offsite power caused by grid failures at a frequency equal to or greater than once in 20 site-years in accordance with RG 1.155.
FPL provided response to GL 2006-02 in letter L-2006-073. The response included, in part, discussion of the formal interface agreement between St. Lucie and the FPL Transmission System Operator (TSO) as well as the associated implementing procedures, the TSO contingency analysis program, related operator and Work Control personnel training, offsite power operability declarations and entry into applicable Technical Specification action statements upon notification of potential degraded grid conditions, consideration of potential grid degradation/instability in the performance of risk assessments required by 10 CFR 50.65(a)(4), and compliance with GDC 17, Electric Power Systems.
UNIT 1 8.2-7 Amendment No. 27 (04/15)
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REFER TO DRAWING 8770-G-417 AMENDMENT NO. 19 (10/02) FLORIDA POWER & LIGHT COMPANY ST. LUCIE PLANT UNIT 1 SWITCHYARD ONE-LINE DIAGRAM FIGURE 8.2-2 Amendment No. 2 7 (04/15) FLORIDA POWER & LIGHT COMPANY 20 14 GRID STABILITY ANALYSIS CASE 1 Amendment No. 2 7 (04/15) FLORIDA POWER & LIGHT COMPANY 20 14 GRID STABILITY ANALYSIS CASE 1
Amendment No. 2 7 (04/15) FLORIDA POWER & LIGHT COMPANY 20 14 GRID STABILITY ANALYSI S CASE 2 Amendment No. 2 7 (04/15) FLORIDA POWER & LIGHT COMPANY 20 14 GRID STABILITY ANALYSIS CASE 2
Amendment No. 2 7 (04/15) FLORIDA POWER & LIGHT COMPANY 20 14 GRID STABILITY ANALYSIS CASE 3 Amendment No. 2 7 (04/15) FLORIDA POWER & LIGHT COMPANY 20 14 GRID STABILITY ANALYSIS CASE 3
Amendment No. 2 7 (04/15) FLORIDA POWER & LIGHT COMPANY 20 14 GRID STABILITY ANALYSIS CASE 4 Amendment No. 2 7 (04/15) FLORIDA POWER & LIGHT COMPANY 20 14 GRID STABILITY ANALYSIS CASE 4
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In addition, in each Class 1E 480V Bus (1A2 and 1B2) utilizes two undervoltage definite time delay relays in a 2-out-of-2 coincident logic scheme. These relays are also interlocked with a engineered safeguards features actuation signal (ESFAS) to ensure adequate starting voltages during accident conditions. The relays are set to actuate at no less than 415 volts (86.5% of 480 volts) with a time
delay of 8 +/- 1 seconds. This setpoint is equivalent to 3850 volts (92.5% of 4160 volts) on the 4160 volt
busses under accident conditions with all the normal and all the ESFAS initiated loads operating.
For sustained degraded voltages concurrent with or without a safeguard signal, all the above
undervoltage schemes will initiate automatic disconnection from the offsite sources, load shedding
diesel generator starting and load sequencing. These systems will be bypassed 0.2 seconds after
diesel generator breaker closing and automatically reinstated following breaker tripping.
c)Compliance With PSB-1 NRC Staff Positions - Evaluation
St. Lucie 1 has been license d as not requiring full compliance with the requirement s of PSB-1, dated July 1981.
The evaluation below reflects the degree of compliance of the existing system.i.NRC Staff Position 1
- Second Level of Undervoltage or Overvoltage Protection with a Time Delay Each position is eval uated against St. Lucie Plant degraded grid undervoltage protection system.
Position B.1.a)The selection of voltage and time setpoints shall be determined from an analysis of the voltage requirements of the safety related loads at all onsite system distribution levels; 1)The setpoints of not less than 3831 volts (92.1
% of 4160) with a time delay of 18 + 2 seconds for non-accident conditions, and not less than 415 volts (86.5% of 480 volts) with a time delay 8
+/- 1 seconds for accident conditions will protect the Class 1E equipment including relays, contactors , and other components whose functional performance would be inadequate because of undervoltage. These setpoints were derived on the basis of the auxiliary system analysis which met criteria of providing acceptable voltage for all the
Class 1E equipment required to perform safety functions.
B.1.b)Two separate time delays shall be selected for the second level of undervoltage
protection based on the following conditions
- 1)The first ti me delay should be of a duration that established the existence of a
sustained degraded voltage condition (i.e., something longer than a motor
starting transient). Following this delay, an alarm in the control room should
alert the operator to the degraded condition. The subsequent occurrence of a
safety injection actuation signal (SIAS) should immediately separate the Class
1E distribution system from the offsite power system.
8.3-5a Amendment No. 17 (10/99) 2)The second time delay should b e of a limited duration such that the permanently connected Class 1E loads will not be damaged. Following this delay, if the operator has failed to restore adequate voltages, the Class 1E distribution system should be automatically separated from the offsite power system. Bases and justification must be provided in support of the actual delay chosen.
A voltage level has been established, which, when reached, will be alarmed in the control room. This level has been chosen as the 4160 volt bus voltage corresponding to a full power operation with a minimum predicted sustained grid voltage of 230 kV. This voltage level has been found to be safe to operate with, but since it represents an excursion from normal operational practices it was established as an appropriate alarm level. The time delay for that setpoint has been chosen to assure that starting of the largest motor in the 4160 volt system will not result in an inadvertent actuation of the protective relays. A SIAS signal concurrent with the alarm will not, by itself , result in a system separation from the offsite power, EDG start, etc.
A separate voltage setpoint has been derived to perform that function, and it is based on the minimum allowable voltage of the Class 1E equipment required to mitigate the accident.
This setpoint has been chosen to be no lower than the minimum allowable
voltage for any equipment as reflected at the 480 volt Class 1E bus with a time delay such as not to interfere with the accident scenario emergency diesel
generator loading.
B.1.c)The voltage sensors shall be designed to satisfy the following applicable requirements derived from IEEE Std. 279-1971, "Criteria for Protection Systems for Nuclear Power Generating Stations";
1)Clas s 1E equipment shall be utilized and shall be physically located at and electrically connected to the Class 1E switchgear.
All the individual components of the undervoltage/degraded voltage protective relaying are Class 1E and are located within Class 1E switchgear.
2)An independent scheme shall be provided for each division of the Class 1E power system.
An independent protective relaying scheme is provided for each division of the Class 1E power system.
3)The undervoltage protection shall include coincidence logic on a per bus basis
to preclude spurious trips of the offsite power source.
The protective scheme includes coincident logic therefore assuring that no spurious actuation of individual relay will result in a spurious trip of the offsite
power source.
8.3-5aa Amendment No. 12, (12/93) 4)The voltage sensors shall automatically initiate the disconnection of offsite power sources whenever the voltage setpoint and time delay limits (cited in
Item 1.b.2 above) have been exceeded.
Once the voltage setpoints and time delay limits are exceeded, the offsite power source will be disconnected without a need for meeting any other conditions.
5)Capability for test and calibrat ion during power operation shall be provided.
The protective scheme implemented allows for testing and calibration during
power operations.
- 6) Annunciations must be provided in the control room for any bypasses
incorporated in the design.
Relay test is annunciated in the control room. There are no other bypasses incorporated in the design.
B.1.d)The Technical Specifications shall include limiting conditions for operation, surveillance requirements, trip setpoints with minimum and maximum limits, and allowable values for the second-level voltage protection monitors and associated time delay devices.
1)The Technical Specifications include requirements undervoltage/degraded grid voltage systems, which include trip setpoints surveillance requirements and limiting conditions for operation. Trip setpoints are included as limit only to allow flexibility in choice of more conservative values.
8.3-5b Amendment No. 17 (10/99)
B.2)The Class 1E bus load shedding scheme should automatically prevent shedding during sequencing of the emergency loads to the bus. The load shedding feature should, however, be reinstated upon completion of the load sequencing action. The technical
specifications must include a test requirement to demonstrate the operability of the
automatic bypass and reinstatement features of least once per 18 months during
shutdown.In the event an adequate basis can be provided for retaining the load shed feature during the above transient conditions, the setpoint value in the Technical Specifications
for the first level of undervoltage protection (loss of offsite power) must specify a value
having maximum and minimum limits. The basis for the setpoints and limits selected must be documented.
The load-shed featur e is bypassed once the onsite sources are supplying the Class 1E buses. This bypassing occurs 0.2 seconds after the diesel generator breakers close
and is auto-reinstated following breaker tripping. This bypasssing/reinstating is
accomplished by utilizing close/trip signals from the diesel generator output breakers.
B.3)The voltage levels at the safety-related buses should be optimized for the maximum
and minimum load conditions that are expected throughout the anticipated range of
voltage variations of the offsite power sources by appropriate adjustment of the voltage
tap settings of the intervening transformers. The tap settings selected should be based
on an analysis of the voltage at the terminals of the Class 1E loads. The analyses
performed to determine minimum operating voltages should typically consider
maximum unit steady state and transient loads for events such as a unit trip, loss-of-
coolant accident, startup or shutdown; with the offsite power supply (grid) at minimum
anticipated voltage and only the offsite source being considered available. Maximum
voltages should be analyzed with the offsite power supply (grid) at maximum expected
voltage concurrent with minimum unit load (i.e., cold shutdown, refueling). A separate
set of the above analyses should be performed for each available connection to the
offsite power supply.
The system analysis was performed for both normal and accident operational loading coupled with minimum transmission system voltages with the auxiliary system
supplied via the start-up transformer. Further, minimal loading and maximum expected
transmission system voltage were analyzed as to the impact on the equipment and
found not to exceed the allowable limits. Similarity, system was analyzed, when
powered via the auxiliary transformer, with a maximum and minimum allowable main
generator output voltages. In all of the cases analyzed, system performance was such
as to assure performance of the safety functions of the Class 1E equipment without
exposure to unacceptably low/high voltages.
B.4)The analytical techniques and assumptions used in the voltage analyses cited in Item 3 above must be verified by actual measurement. The verification and test should be
performed prior to initial full-power reactor operation on all sources of offsite power by:
8.3-5c Amendment No. 17 (10/99) a)loading the station distribution buses, including all Class 1E buses down to the 120/208 volt level, to at least 30%;
b)recording the existing grid and Class 1E bus voltages and bus loading down to the 120/208 volt level at steady state conditions and during the starting of both a large Class 1E and non-Class 1E motor (not concurrently);
Note: To minimize the number of instrumented locations, (record ers) during the motor starting transient tests, the bus voltages and loading need only be recorded on that string of buses which previously showed the lowest analyzed voltages from Item 3 above.
c)using the analytical techniques and assumptions of the previous voltage analyses cited in Item 3 above, and the measured existing grid voltage and bus loading conditions recorded during conduct of the test, calculate new set of voltages for all the Class 1E buses down to the 120/208 volt level; d)compare the analytical derived voltage values against the test results.
With good correlation between the analytical results and the test results, the test verification requirement will be met. That is, the validity of the mathematical model used in performance of the analyses of Item 3 will have been established; therefore, the validity of the results of the analyses is also established. In general, the test results should not be more than 3% lower than the analytical results; however, the difference between the two when subtracted from the voltage levels determined in the original analyses should never be less than the Class 1E equipment rated voltages.
The analytical techniques used in the St. Lucie Unit 1 analysis were not specifically verified, as required by the NRC, since the position was developed and formalized after St. Lucie Unit 1 was operational. However, same
techniques were used in the system analysis and verified to provide good
correlation by actual test on St. Lucie Unit 2.
Conclusion Based on the above Undervoltage/Degraded Grid Voltage Detection System meets the
intent of PSB-1.
All of the staff's requirements and design bases criteria have been met. The voltage
and time delay trip settings will protect the Class 1E equipment from sustained
degraded voltages from the offsite sources during accident and non-accident
conditions.
8.3-5ca Amendment No. 12, (12/93)
Bypassing the load-shed feature by using a close signal from the dies el generator breaker to prevent an adverse interaction when the onsite sources are supplying the Class 1E buses. The load-shed feature is auto-reinstated following diesel generator breaker tripping. Thus, NRC Staff
Position 2 is met.
The existing Techn ical Specifications include tests which have been reviewed and found to meet the requirements of NRC Staff Position 3.
Analysis of station electric system voltages was performed under steady-state conditions with the full plant running load and minimum design switchyard voltage supplying the onsite system
through the startup transformers. The results of this analysis demonstrates that, as well as
also shown in the analysis of the Unit Auxiliary Transformer, all voltages on the Class 1E systems remain above minimum acceptable design conditions.
The worst case starting transient was also analyzed for the most limiting conditions (the 1A system with the 1AB bus connected, since it is the most heavily loaded with all normal plant
running loads on the buses) when the startup transformer is supplying the system and offsite
switchyard voltage is at the design minimum of 235 kV.
8.3.1.1.5 120/208 Volt System Power is supplied for normal lighting and other plant loads requiring an unregulated power supply by the
120/208 volt system. This system consist of distribution panels and transformers fed from 480 volt
MCCs.Some of the 120
/208 volt panels feed safety related loads such as engineered safety features process mo n i toring instrumentation. In all such cases, the stepdown transformer is fed from an emergency MCC and a Class 1E power panel. Safety related loads, as well as some non-safety related loads are connected to these panels.
The 120/208 volt 3 phase 4 wire system has a solid neutral ground.
8.3.1.1.6 Instrument Power Supply System Four redundant 120 volt ac single phase instrument power buses (1MA, 1MB, 1MC and 1MD) provide power to essential instrumentation and control loads under all operating conditions. Each bus is
supplied separately from an inverter connected to one of the two Class 1E 125 volt dc buses described
in Section 8.3.2.1. The instrument power supply system one line diagram is shown on Figure 8.3-3A.
To permit maintenance of any inverter without disabling the corresponding instrument bus, two maintenance bypass buses (1A and 1B) fed from Isolimiters 1A and 1B, respectively, are provided.
Instrument buses can be connected to the bypass busses by individual "make before break" transfer
switches. Breaker interlocks prevent simultaneous connection of more than one instrument bus to a
maintenance bypass bus. Each of the four redundant measurement channels of the nuclear
instrumentation and reactor protective systems equipment described in Section 7.2 is supplied from a
separate bus of 8.3-5d Amendment No. 17, (10/99)
- 3) The generator is capable of starting , accelerating and supplying the above loads in their proper sequence without exceeding 20 percent voltage drop at its terminals.
4)The diesel generator is capable of starting, accelerating and running the largest motor
(600 HP nameplate) at any time after the automatic loading sequence is over , assuming that the motor had failed to start automatically.
8.3-6a Amendment 15, (1/97) 5)The diesel generator sets are capable of reaching full speed and voltage within 10 seconds after receiving a signal to start.
6)The speed of the diesel generator set will not exceed 103 percent of nominal speed (900 rpm) during recovery from transients caused by disconnection of the largest single
load. The engine trip set points is 1031 rpm. (114.5% nominal) 7)The recovery of the diesel generator from transients will be within 10 percent of nominal
voltage and 2 percent of nominal frequency within 40 percent of each load sequence
time interval. The recovery from transients was verified during preoperational testing.
8)Predicted loads were verified during preoperational testing.
Each diesel generator consists of two diesel engines mounted in tandem with a 3500 kw generator coupled directly between the engines.
Each engine in each diesel generator set has a self-contained cooling system which consists of a forced circulation cooling water system which cools the engine directly and an air cooled radiator
system which removes the heat from the cooling water. The cooling water pump and radiator fan are driven directly from the engine crankshaft. After starting, the diesel generator set cooling system requires no external source of power and does not depend on any plant cooling system.
The engine of each diesel generator set has a self-contained lube oil system consisting of a lube oil sump located at the base of the engine, a lube oil pump, piping, and a heat exchanger. The lube oil heat exchanger is served by the diesel generator set cooling water system. No external source of power or
other plant system is required for the diesel generator set lube oil system.
Design data for the diesel generator sets are given in Table 8.3-3.
- b. Starting System Each diesel generator set has an independent air starting system. Each diesel generator is provided with two sets of two air receivers. Each set of air receivers has a sufficient air charge for starting a cold
diesel generator set five times. Each diesel generator set is also provided with two air compressors, one
of which is driven by a separate diesel engine , the other is driven electrically. These compressors
provide charging air to the two sets of air receivers. The diesel generator sets are started by the air starting systems 8.3-7 Amendment 18, (04/01)
If the diesel is started as a result of a SIAS or loss of offsite power, all but two diesel generator lockout signals are overriden. Those which remain functional are engine overspeed and generator differential.
Overriding all but two of the lockout signals reduces the probability of spuriously tripping a diesel
generator when it may be required to shut down the plant or mitigate the consequences of an accident.
The rationale for retaining the engine overspeed and generator differential lockouts is in mitigating the probability of seriously dam aging a diesel should one of these adverse conditions occur. The lockouts may permit a repair and return to serv ic e during an accident or loss of offsite power condition. The two trips that are not overriden are commonly used in power plant application and have histories of highly
reliable operation. The reliability of the two lockouts discussed above warrants maintaining their
protective capability during both normal and accident conditions.
By means of potential and current transformer test blocks and a test position of the diesel generator circuit breakers the capability is provided to periodically test the protective relaying components and the
system as a whole.
Figures 8.3-6b and e show the diesel generator lockout relays.
- f. Instrumentatio n All power supply sources for the diesel generator instrumentation and control system are in accordance with the redundancy criteria discussed in Section 8.3.1.2.
The following parameters are monitored and indicated either locally or in the control room:
Control Room Local 1)generator voltage
- 2)4 kV bus voltage
- 3)generator current
- 4)generator watts
- 5)generator watt-hours
- 6)generator frequency
- 7)generator reactive power
- 8)generator field voltage
- 9)generator field current
- 10)diesel generator elapsed
- running time 11)generator breaker position
- 8.3-10 Amendment 18, (04/01)
The Kerite 600 volt power cables are insulated with a high temperature kerite insulation (HTK) andcovered with black heavy duty flame resistant (FR) jackets. The Kerite 600 volt control cables are insulated with kerite flame resistant insulation and covered with heavy duty flame resistant (FR) jackets. New instrumentation cables are 600 volt rather than 300 volt cable originally used. The Kerite 600 volt instrumentation cables are insulated with kerite flame resistant insulation, polymer layer, mylar oraluminum mylar and glass mylar core tapes, with flame resistant (FR) jacket. Kerite insulation maintains the dry/wet/alternately wet and dry properties of crosslinked polyethylene cable while offering greatly enhanced fire retardancy capability. These cables are Post-LOCA qualified.The Okonite 600 volt low voltage power, control and instrumentation cables are insulated with X-Olene FNR (XLP) insulation and covered with a flame resistant Okolon (Hypalon) jackets. The Okonite 300 volt instrumentation cables are insulated with X-Olene FNR (XLP) insulation and covered with flame resistant Okolon (Nypalon) jackets. Okonite insulation maintains the dry/wet/alternately wet and dry properties of crosslinked polyethylene cable while offering enhanced fire retardancy capability. These cables are Post-LOCA qualified.
8.3-12a Am. 4-7/86
PAGES 8.3-19 AND 8.3-20 HAVE BEEN INTENTIONALLY DELETED
8.3-19 Am. 7-7/88
During the reliability tests conducted by the manufacturer to demonstrate the confidence level to perform the diesel function, i.e., the 300 start test, periodic maintenance functions were performed. To insure an in situ confidence level equivalent to that demonstrated by the manufacturer, these functions will be
performed on site. The frequency of maintenance functions will be consistent with the schedule followed
by the manufacturer during the shop tests.
Preoperational testing was performed to verify that all components, automatic and manual controls, and sequences of the integrated emergency power system functioned as required by the plant safety
analysis.A switch is provided for testing each of the 4.16 kV emergency buses (1A3 and 1B3) load shed relays (27X-1, 27X-2, etc.). Each switch, which has a spring return to normal operation, has three positions -
lamp test, normal, and relay test. The "lamp test" position is used to verify that the lamp is working.
Turning the test switch to the "relay test" position bypasses the undervoltage trip actuating relay
contacts (disconnecting them from the actuating circuit) and connects them to the test lamp circuit.
Similar arrangement is provided to test the 480 V load center degraded voltage relays. Schematics for
this system are provided - see Figures 8.3-6g, 6h and 6i.
A separate test circuit is provided for the 4.16 kV emergency busses (1A3 and 1B3) loss of/degraded voltage detection relays (see Figures 8.3-17 and 8.3-17a). A six (6) position selector switch and a test pushbutton allows individual testing of each of the relays and their associated timers.
Periodic testing of the system after plant start-up, will be performed as described in the plant Technical Specifications.
The diesel generators will be inspected in accordance with a licensee-controlled maintenance program. This program will require inspection in accordance with procedures prepared in conjunction with the manufacturer's recommendations for this class of standby service. Changes to the maintenance program will be controlled under 10CFR50.59.
8.3-34 Amendment No.18, (04/01)
groups A and B are each capable of supplying the minimum dc power requirements to safely shut down the plant and/or mitigate the consequences of a LOCA.
Load group A is served by dc bus 1A and load group B by dc bus 1B. Load group AB is served by dc bus 1AB which is normally tied to either (but never both) dc bus 1A or 1B corresponding to the manner
in which the 4.16kV and 480 V AB busses are connected to their respective A or B busses. There are
two breakers in series in each tie which are key interlocked to prevent the 1AB bus from being simultaneously connected to both the 1A and 1B busses. The dc loads served by each bus are given in
Table 8.3-4. To prevent the simultaneous and inadvertent opening of the breakers (72-2-A and 72-2B)
from both station batteries (1A and 1B respectively) to their 125 volt dc busses, an auxiliary switch for
remote position monitoring is provided. The resultant annunciators will alarm in the control room upon
opening of the battery bus breakers.
The 125 volt dc busses will be supplied by battery chargers 1A and 1AA for train "A" and 1B and 1BB for train "B". Each charger has a 300 amp capacity and will operate continuously. The load in these chargers will be equally distributed by means of a load sharing device.
Each charger is sized to carry normal dc load and to recharge a battery from 1.75 volts per cell. The worst loading condition on the battery chargers occurs during post LOCA condition with loss of off-site
power. After the initial 40 second battery operation, each battery charger is sufficient to recharge its
battery within a 1/2 hour period. Two 125 volt dc battery chargers operate on each of the busses. A fifth 125 volt dc battery charger on the AB bus provides a backup for the four operating 125 volt dc chargers.
Each of the two 125 v lead-calcium type station safety batteries is rated at 2400 ampere/hr at an 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> discharge rate. The above rating is sufficient for a 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> emergency period without assistance from a battery charger. Figure 8.3-14 gives the station battery emergency load profile.
The battery chargers and inverters are automatically loaded on the diesel generator approximately 40 seconds after loss of offsite power, thus returning the DC system to normal. The above 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> battery
rating is more than adequate for this design limiting case of 40 second battery operation.
The turbine generator DC emergency pump motors (bearing oil and seal oil pumps
), are fed from the non-safety batteries and DC Bus 1C or 1D. This non-safety bus is normally supplied from a 300 ampere charger identical with the safety system chargers.
8.3-36 Amendment 1 5, (1/97)
8.3.2.2.5 Conformance With Appropriate Quality Assurance Standards The quality control of design, fabrication, shipment, field storage, installation and component checkout, and the documentation of such measures are carried out in accordance with the quality assurance
program as reflected in Corporate Quality Program.
8.3.2.2.6 Service Environment All essential portions of the dc power system are located in the reactor auxiliary building in areas where the accident ambient conditions are not expected to be significantly different from normal ambient
conditions. Refer to Section 8.3.1.2.6 for discussion of cable qualification, construction and methods of
installation.
8.3.2.2.7 Natural Phenomena All portions of the dc power system necessary to achieve safe plant shutdown or mitigate the consequences of a design basis accident are designed as seismic Class I. This includes station
batteries and racks, battery chargers, distribution panels and cabling. All components are located in
the seismic Class I reactor auxiliary building. Refer to Section 3.10 for discussion of the seismic design
of Class I electrical components. Due to their location within the reactor auxiliary building, all
components of the dc power system necessary to achieve safe plant shutdown are protected from the
effects of design wind loadings, external missiles and maximum flood levels.
8.3.2.2.8 Regulatory Items Generic Le t ter 91-06, "Resolution of Generic Issue A-30 Adequacy of Safety Related DC Power Supplies".
The response to this ge neric letter provided in FPL letter L-91-291 identified instrumentation which provides indication and/or alarms in the control room with the following system information:
- 1) battery breaker in open position (alarm), 2) battery charger disconnect or breaker open (alarm), 3) bus voltage (indication, no alarm), 4) dc ground (alarm), 5) dc under voltage (alarm), 6) dc over voltage (alarm), and
- 7) battery charger failure (alarm).
8.3.2.3 Testing and Inspection The manufacturers of electrical equipment perform production shop tests to verify circuit continuity, operability and insulation resistance as called for by the equipment specifications. Seismic and
environmental testing of the original plant equipment are discussed in Sections 3.10 and 3.11.
Pre-operational testing was performed to verify that all components, automatic and manual controls, and sequences of the integrated emergency power system functioned as required by the plant safety
analysis. Periodic testing after plant startup is as required by the plant Technical Specifications. When
these tests are conducted on the batteries, such that the battery bus breakers are open, the control
room operators are notified via an alarm.
8.3-39 Amendment No. 17 (10/99)
PAGE LEFT INTENTIONALLY BLANK 8.3-51 Amendment No. 12, (12/93)
PAGE LEFT INTENTIONALLY BLANK 8.3-52 Amendment No. 12, (12/93)
PAGE LEFT INTENTIONALLY BLANK 8.3-53 Amendment No. 12, (12/93)
PAGE LEFT INTENTIONALLY BLANK 8.3-54 Amendment No. 12, (12/93)
PAGE LEFT INTENTIONALLY BLANK 8.3-55 Amendment No. 12, 12/93)
PAGE LEFT INTENTIONALLY BLANK 8.3-56 Amendment No. 12, (12/93)
PAGE LEFT INTENTIONALLY BLANK 8.3-57 Amendment No. 12, (12/93)
PAGE LEFT INTENTIONALLY BLANK 8.3-58 Amendment No. 12, (12/93)
TABLE 8.3-6
SUMMARY
OF SEISMIC STRESSES FOR UNDERGROUND C0NDUITS Axial Stress (1) Bending Stress Shear Stress (1)A.Straight Conduit 571 psi 0 psi 286 psi B.Bent Conduit (90 o bend)571 psi 0 psi 286 psi Allowable St resses: Tensile 7000 psi Compressive 9000 psi Flexual 12,000 psi Shear 8,000 psi (1)Axial stresses occur with axial displacements.
Shear stresses occur with transverse displacements.
Stresses are based on a shear wave velocity of 700 ft/sec.
8.3-69
MAIN ONE LINE WIRING DIAGRAM FIGURE 8.3-1 Amendment No. 15 (1/97)
COMBINED MAIN AND AUXILIARY ONE LINE DIGRAM FIGURE 8.3-1a Amendment No. 15 (1/97)
AUXILIARY ONE LINE DIGRAM FIGURE 8.3-2 Amendment No. 15 (1/97) 480 V MISCELLANEOUS, 125V D-C AND VITAL A- C ONE LINE, SH.1 FIGURE 8.3-3a Amendment No. 15 (1/97) 480 V MISCELLANEOUS, 125V DC AND VITAL A C ONE LINE, SH.2 FIGURE 8.3-3b Amendment No. 15 (1/97)
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- m"V POWIA CHTH 1A*I S* nanl TO IUl1M IYICMAO CMlCI H.IO.tl VOLTAIC
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- 1.011c iilOTt: L04ilC LAllE FOlll Dl. IO. ti UCln IUI 11-J H'LACU IUI ITillOU, $910UT SIHAL. <$> ...... Amendment No. 19 (10/02) FLORIDA POWER & LIGHT COMPANY ST. LUCIE PV.NT UNIT 1 Typical Diesel G"'nerator Automatic Starting Logic FIGURE 8.3-5 SCHEMATIC DIAGRAM DIESEL GENERATOR 1A-START CKTS FIGURE 8.3-6a Amendment No. 15 (1/97)
- *
- Refer to drawing 8770-8-326 Sheet 956 FLORIDA POWER & LIGHT COMPANY ST. LUCIE PLANT UNIT 1 SCHEMATIC DIAGRAM DIESEL GENERATOR LOCKOUT RELAY FIGURE 8.3-6b Amendment No. 15 (1/97)
SCHEMATIC DIAGRAM DIESEL GENERATOR 1A BKR FIGURE 8.3-6c Amendment No. 15 (1/97)
SCHEMATIC DIAGRAM DIESEL GENERATOR 1B-START CKTS FIGURE 8.3-6d Amendment No. 15 (1/97)
SCHEMATIC DIAGRAM DIESEL GENERATOR 1B -START CKTSFIGURE 8.3-6d1Amendment No. 18, (04/01)
SCHEMATIC DIAGRAM DIESEL GENERATOR 1B-LOCKOUT RELAY FIGURE 8.3-6e Amendment No. 15 (1/97)
SCHEMATIC DIAGRAM DIESEL GENERATOR 1B BKR FIGURE 8.3-6f Amendment No. 15 (1/97)
SCHEMATIC DIAGRAM 4160V SWGR 1A3 LOAD SHEDDING RELAYS FIGURE 8.3-6g Amendment No. 15 (1/97)
SCHEMATIC DIAGRAM 4160V SWGR 1B3 LOAD SHEDDING RELAYS FIGURE 8.3-6h Amendment No. 15 (1/97)
SCHEMATIC DIAGRAM 4160V SWGR 1AB LOAD SHEDDING RELAYS FIGURE 8.3-6i Amendment No. 15 (1/97)
REACTOR AUXILIARY BUILDING EL.43'-0 62'-0 CONDUIT, TRAYS & GROUNDING-SH 1 FIGURE 8.3-7 Amendment No. 15 (1/97)
REACTOR AUXILIARY BUILDING EL.19'-6 CONDUIT, TRAYS & GROUNDING-SH 1 FIGURE 8.3-8 Amendment No. 15 (1/97)
REACTOR AUXILIARY BUILDING EL.19'-6 CONDUIT, TRAYS & GROUNDING-SH 2 FIGURE 8.3-9 Amendment No. 15 (1/97)
REACTOR CONTAINMENT BLDG. EL 18'-0 CONDUIT, TRAYS & GROUNDING PLAN FIGURE 8.3-10 Amendment No. 15 (1/97)
REACTOR AUX. BLDG PENETRATION AREA CONDUIT TRAYS AND GROUNDING FIGURE 8.3-11 Amendment No. 15 (1/97)
REACTOR CONTAINMENT BLDG PENETRATION DETAILS FIGURE 8.3-12 Amendment No. 15 (1/97)
YARD DUCT RUNS FIGURE 8.3-13 Amendment No. 15 (1/97)
- * * * * --AIR START SYSTEM AlR DRYER IDLE CONTROL CABINET.
LOUVER (TYFICAL SEE FIG. 8.3-15AI Alfi STARTING SYSTEM SECTION A-A MONORAIL MONORAIL 'i. i I I MONORAIL MCC 1A7 GEN CT DIESEL GEN 1A <<t. CONT CAB SECTION 8-B MISSILE PROTECTION (TYPICAL)
"'--fiADIATOR EXHAUST
- IDLE START CONTROL CABINET DIESEL GEN IB 'i. MCC 1B7 Am. 2-7/84 FLORIDA POWER & LIGHT COMPANY ST. LUCIE PLANT UNIT 1 DIESEL GENERATOfi BUILDING GENERAL ARRANGEMENT AND ELEVATION DRAWING FIGURE 8.3-15
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,,* () --r t FLORIDA POWER & LIGHT ST. LUCIE PLANT 1 DIESEL GENERATOR L:)UVERS FIGURE 8. 3-lSA CABLE AND CONDUIT LIST INSTALLATION DETAILS FIGURE 8.3-16 Amendment No. 15 (1/97)
CONTROL WIRING DIAGRAM 4.16 KV SWGR. 1A3 UNDERVOLTAGE RELAYING/TEST FIGURE 8.3-17 Amendment No. 15 (1/97)
CONTROL WIRING DIAGRAM 4.16 KV SWGR. 1B3 UNDERVOLTAGE RELAYING/TEST FIGURE 8.3-17a Amendment No. 15 (1/97)
., FLORIDA POWER & LIGHT COMPANY ST. LUCIE PLANT UNIT 1 RAB BATTERY ROOMS SINR & SHOWER ENCLOSURES FIGURE 8. 3-18