Control system for a steam generator receiving heat from a nuclear reactor

Claim 1

A VAPOR PRODUCING PLANT OPERATING UNDER VARIABLE VAPOR OUTPUT CONDITIONS, COMPRISING: A NUCLEAR REACTOR, A VAPOR GENERATOR, A HEAT CARRIER FLUID, MEANS FOR CONDUCTING SAID HEAT CARRIER FLUID AS A COOLANT THROUGH SAID NUCLEAR REACTOR AND AS A HEATING AGENT THROUGH SAID VAPOR GENERATOR, SAID VAPOR GENERATOR COMPRISING TUBULAR HEAT EXCHANGE MEANS CONDUCTING AN OPERATING MEDIUM THROUGH SAID VAPOR GENERATOR IN COUNTERFLOW RELATION TO SAID HEAT CARRIER FLUID, SAID HEAT EXCHANGE MEANS COMPRISING AN EVAPORATOR WHEREIN THE OPERATING MEDIUM IS EVAPORATED AND A SUPERHEATER FOR SUPERHEATING THE EVAPORATED OPERATING MEDIUM, SAID SUPERHEATER HAVING AN INLET, AN OUTLET, AND AN INTERMEDIATE PORTION THEREBETWEEN, A TEMPERATURE SENSING MEANS CONNECTED TO SAID SUPERHEATER FOR SENSING THE TEMPERATURE OF SAID INTERMEDIATE PORTION OF SAID SUPERHEATER, AND MEANS FOR CONTROLLING THE RATE OF SUPPLY OF LIQUID OPERATING MEDIUM TO SAID VAPOR GENERATOR, SAID CONTROL MEANS BEING OPERATIVELY CONNECTED TO SAID TEMPERATURE SENSING MEANS FOR INCREASING THE RATE OF SUPPLY OF LIQUID OPERATING MEDIUM AT INCREASING TEMPERATURE OF SAID INTERMEDIATE PORTION OF SAID SUPERHEATER, AND CONVERSELY.

Claim 3

A METHOD OF CONTROLLING THE RATE OF SUPPLY OF A LIQUID OPERATING MEDIUM TO A VAPOR GENERATOR INCLUDING AN EVAPORATOR AND A SUPERHEATER FOR SUPERHEATING THE EVAPORATOR OPERATING MEDIUM, THE VAPOR GENERATOR BEING HEATED BY A HEAT CARRIER FLUID FLOWING IN COUNTERFLOW RELATION TO THE OPERATING MEDIUM OF THE VAPOR GENERATOR AND FLOWING AS A COOLANT THROUGH A NUCLEAR REACTOR, THE METHOD COMPRISING THE STEPS OF: SUBSTANTIALLY MAINTAINING A PREDETERMINED TEMPERATURE OF THE HEAT CARRIER FLUID LEAVING THE NUCLEAR REACTOR AND ENTERING THE VAPOR GENERATOR, MEASURING THE TEMPERATURE OF THE OPERATING MEDIUM OF THE VAPOR GENERATOR AT AN INTERMEDIATE POINT OF THE SUPERHEATER FORMING PART OF THE VAPOR GENERATOR, BEFORE SUPERHEATING IS COMPLETED, FORMING A CONTROL SIGNAL CORRESPONDING TO THE AFORESAID TEMPERATURE OF THE OPERATING MEDIUM, FORMING A CONTROL SIGNAL CORRESPONDING TO THE TEMPERATURE OF THE HEAT CARRIER FLUID LEAVING THE VAPOR GENERATOR, COMBINING SAID CONTROL SIGNALS TO FORM A COMBINED SIGNAL, AND CONTROLLING THE RATE OF SUPPLY OF LIQUID OPERATING MEDIUM TO THE VAPOR GENERATOR ACCORDING TO SAID COMBINED SIGNAL.

Claim 4

A METHOD OF CONTROLLING THE RATE OF SUPPLY OF A LIQUID OPERATING MEDIUM TO A VAPOR GENERATOR INCLUDING AN EVAPORATOR AND A SUPERHEATER FOR SUPERHEATING THE EVAPORATOR OPERATING MEDIUM, THE VAPOR GENERATOR BEING HEATED BY A HEAT CARRIER FLUID FLOWING IN COUNTERFLOW RELATION TO THE OPERATING MEDIUM OF THE VAPOR GENERATOR AND FLOWING AS A COOLANT THROUGH A NUCLEAR REACTOR, THE METHOD COMPRISING THE STEPS OF: SUBSTANTIALLY MAINTAINING A PREDETERMINED TEMPERATURE OF THE HEAT CARRIER FLUID LEAVING THE NUCLEAR REACTOR AND ENTERING THE VAPOR GENERATOR, MEASURING THE TEMPERATURE OF THE OPERATING MEDIUM OF THE VAPOR GENERATOR AT AN INTERMEDIATE POINT OF THE SUPERHEATER FORMING PART OF THE VAPOR GENERATOR, BEFORE SUPERHEATING IS COMPLETED, FORMING A CONTROL SIGNAL CORRESPONDING TO THE AFORESAID TEMPERATURE OF THE OPERATING MEDIUM, FORMING A CONTROL SIGNAL CORRESPONDING TO THE TEMPERATURE OF THE HEAT CARRIER FLUID LEAVING THE VAPOR GENERATOR, COMBINING SAID CONTROL SIGNALS TO FORM A COMBINED SIGNAL, AND CONTROLLING THE RATE OF SUPPLY OF LIQUID OPERATING MEDIUM TO THE VAPOR GENERATOR ACCORDING TO SAID COMBINED SIGNAL.