Diesel generator

Many redundant safety features were provided at the SRP. These included a moderator dump tank, gadolinium nitrate solution as emergency absorber, continuously mnning diesel generators, and a 95 x 10 -L (25 x 10 -gal) elevated water tank for each reactor, for assurance of cooling. 

Bunker-fuel specifications for merchant vessels are described by ASTM D 2069, Standard Specification for Marine Fuels. Deep draft vessels carry residual (e.g., No. 6 fuel oil) or distillate-residual blend for main propulsion, plus distillate for start-up, shutdown, maneuvering, deck engines, and diesel generators. Main-propulsion fuel is identified principally by its viscosity in centistokes at 373 K. Obsolete designations include those based on Redwood No. 1 seconds at 100°F (311 K) (e.g., "MD 1500 ) and the designations "Bunker A for No. 5 fuel oil and "Bunker B and "Bunker C for No. 6 fuel oil in the lower-and upper-viscosity ranges, respectively. 

It is common practice to provide a standby emergency source of supply at all important installations such as large factories, railways, airports and other essential services. This is usually achieved with the use of a captive diesel generator (DG) set (Figure 16.1). Here we briefly discuss these machines, their characteristics and selection for a required application. We also consider schemes that are commonly used to start a DG set and run it individually or in parallel with an existing source of supply, which may be another DG set or an infinite bus. 

Figure 16.1 Diesel generator set (Courtesy Kirloskar Electric)...

Captive (emergency) power generation covers the application of a diesel generating set, its starting, protection, synchronizing and load sharing. This forms an important part of power distribution at any installation to provide a standby source of supply,... 

Provision for cooling emergency equipment, e.g. diesel generators if cooling water is disrupted. 

Consider a plant having two power trains A and B with diesel generators DA connected to... 

EPRI NP-2433 addresses diesel generator reliability at nuclear power plants. The sources include plant records, utility records, and LERs. The report gives frequency of failure to start, failure. o continue running, and mean repair times. 

The mode of failure in a test is examined carefully before the failure is included in the database. In the diesel-generator example, unsatisfactory performance may have been reported because of a trip on a low oil pressure signal, high oil temperature, or both. 

Table 6.1-3 ANO- Frontline Support and Support vs Support Dependencies (All requirements for diesel generators as.sume loss of station power j...

Safety-grade equipment such as pumping systems and diesel generators and associated support equipment and electric power distribution is eliminated. 

The accident resulted from a routine safety test of some electrical control equipment at the start of a normal reactor shutdown for routine maintenance. The test was to determine the ability to continue to draw electrical power from a turbine generator during the first minute of coast-down following a station blackout. In a blackout, the reactor automatically scrams and diesel generators start to assume load (about 1 minute required). 

Four onsite power diesel generators that start automatically on loss of offsite power to reduce the frequency of the loss of station AC by an order of magnitude compared with ( , NDl 1 -6. This with the diesel driven auxiliary feedwater pump provides ample recovery imie... 

The tire analysis was assisted by SNL using methods described in NUREG/CR-4840 and the extensive operating history and fire experience. For 94 reactor-years from 1958 and 1987, 20 significant fire events were recorded. Hence, frequencies for the reactor building and the diesel generator buildings of 0.12 and 0.03 /y, respectively. A control room fire has never occurred at a SRS reactor. 

Poloski, J. P. and W. H. Sullivan, Data Summaries of Licensee Event Reports of Diesel Generators at U.S. Commercial Nuclear Power Plants, EG G. March 1980. 

McClymont, A. S. and G. McLogan, Diesel Generator Reliability at Nuclear Power Plants Data and Preliminary Analysis, SAIC. 

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