A reactor protection system (RPS) is a set of
nuclear safety and security
Nuclear safety is defined by the International Atomic Energy Agency (IAEA) as "The achievement of proper operating conditions, prevention of accidents or mitigation of accident consequences, resulting in protection of workers, the public and the ...
components in a
nuclear power plant designed to safely shut down the
reactor and prevent the release of
radioactive
Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is consi ...
materials. The system can "trip" automatically (initiating a
scram
A scram or SCRAM is an emergency shutdown of a nuclear reactor effected by immediately terminating the fission reaction. It is also the name that is given to the manually operated kill switch that initiates the shutdown. In commercial reactor ...
), or it can be tripped by the operators. Trips occurs when the parameters meet or exceed the limit setpoint. A trip of the RPS results in full insertion (by gravity in pressurized water reactors or high-speed injection in boiling water reactors) of all
control rods and shutdown of the reactor.
Pressurized water reactors
Some of the measured parameters for US pressurized water plants would include:
*"High power", auctioneered between high nuclear power and high differential temperature (delta T) between the inlet and outlet of the reactor vessel (a measure of the thermal power for a given RCS flowrate).
*"High startup rate" (active below 10-4 percent power) at low power levels.
*"High pressurizer pressure"
*"Low reactor coolant flow"
*"Thermal margin / low pressure" (reactor power versus RCS pressure)
*"High containment pressure"
*"Low steam generator level"
*"Low steam generator pressure"
*"Loss of load" (main turbine trip)
Each parameter is measured by independent channels such that actuation of any two channels would result in an automatic SCRAM or reactor shutdown. The system also allows manual actuation by the operator.
Boiling water reactors
See also
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Nuclear power
Nuclear power is the use of nuclear reactions to produce electricity. Nuclear power can be obtained from nuclear fission, nuclear decay and nuclear fusion reactions. Presently, the vast majority of electricity from nuclear power is produced ...
*
Nuclear safety and security
Nuclear safety is defined by the International Atomic Energy Agency (IAEA) as "The achievement of proper operating conditions, prevention of accidents or mitigation of accident consequences, resulting in protection of workers, the public and the ...
*
Generation III reactor (evolutionary improvements of existing designs 1996–present)
*
Generation IV reactor
Generation IV reactors (Gen IV) are six nuclear reactor designs recognized by the Generation IV International Forum. The designs target improved safety, sustainability, efficiency, and cost.
The most developed Gen IV reactor design is the sodium ...
(technologies still under development unknown start date, possibly 2030)
References
Nuclear power plant components
Nuclear safety and security
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