A power transformer would be required for the plant auxiliary 

 services and a rectifier for battery changing. The batteries provide emergency 

 control power for relays, instrumentation, and tripping power for the main 

 breaker. 



The generator prime movers would have a full complement of 

 mechanical and electrical indicating and protective devices. 



In-Situ Power Systems 



The preceding discussion on the electrical power transmission system 

 for the selected power levels and cable lengths concerns surface plant facilities. 

 In the in-situ facilities, the power module and the load module may be sepa- 

 rated by less than 100 feet because wet connectors do not exist. As a result, 

 the in-situ power module and the load module must be electrically connected 

 prior to emplacement. 



The operational philosophy of the protection system for in-situ plants 

 is similar to that described earlier for surface plants. On a permanent fault, 

 the load module is electrically isolated from the in-situ power module. The 

 reactor then goes through a controlled shutdown. When the primary source 

 fails, power for the load module is derived from batteries. In an in-situ facility, 

 there is no external station to which fault information can be monitored, nor 

 are there means to provide a remote corrective capability. 



The mode of operation selected as the most cost effective for the 

 in-situ system is to provide protective devices, instrumentation, and main 

 circuit breaker in the power module, with redundant protective and control 

 devices located in the load module for corrective action performed by an 

 operator. The power module for all power levels and ocean depths would 

 also contain the reactor, steam turbine, and generator. Only critical mechan- 

 ical problems and electrical failures will shut down the in-situ plant by 

 energizing various protective relays. All relays, main breaker, switchgear, 

 and monitoring devices are located in the power module. All functions and 

 ability to close or open the main breaker are carried back to the load module 

 by a control cable. 



Shore-Based Power Systems 



For the shore-based system, the maximum length of circuit that 

 could be tolerated while maintaining a 15% maximum voltage drop was 

 considered for loads of 30, 100, 300, 1,000, and 3,000 kw at nominal 

 voltages of 5 kv, 15 kv, and 34.5 kv, with a brief evaluation at 69 kvand 

 115 kv. The maximum incremental distances of 10, 50, 100, and 500 



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