KR-102964132-B1 - REACTOR PROTECTION SYSTEM WITH MULTIPLE COINCIDENCE PROCESSORS

KR102964132B1KR 102964132 B1KR102964132 B1KR 102964132B1KR-102964132-B1

Abstract

The present invention relates to a reactor protection system, and a reactor protection system using multiple coincidence processors according to one embodiment of the present invention, comprising: M channels that equally receive input signals of N different items, wherein M and N are integers greater than 1; M coincidence processors disposed in each of the M channels and receiving input signals of N different items; and a comparison logic processor disposed in each of the M channels and receiving the processing results of the coincidence processors and performing comparison logic to generate a trip signal.

Inventors

이동일
강성곤
이광현
임희택
최선미
이호철

Assignees

한국수력원자력 주식회사

Dates

Publication Date: 20260512
Application Date: 20240116

Claims (9)

As a reactor protection system using multiple simultaneous logic processors, M channels that equally receive input signals of N different items, where M and N are integers greater than 1; M coincidence processors disposed in each of the M channels and receiving input signals of N different items; and A reactor protection system using multiple simultaneous logic processors, comprising a comparison logic processor disposed in each of the M channels and receiving the processing result of the simultaneous logic processor to perform comparison logic (Bistable Processor) and generate a trip signal.
In paragraph 1, A reactor protection system using multiple simultaneous logic processors, wherein the input signals of the above N different items include at least one of pressure, temperature, flow rate, and radioactivity measured in the reactor.
In paragraph 1, A reactor protection system using multiple simultaneous logic processors, wherein each of the simultaneous logic processors disposed in each of the M channels receives the M input signals equally for each of the N different items.
In paragraph 1, Each of the simultaneous logic processors assigned to each of the M channels is A reactor protection system using multiple simultaneous logic processors that receive input signals.
In paragraph 4, The simultaneous logic processors assigned to each of the M channels are A reactor protection system using multiple simultaneous logic processors that generate intermediate values for input signals for each identical item among input signals.
In paragraph 5, A reactor protection system using multiple simultaneous logic processors, wherein the simultaneous logic processors placed in each of the M channels transmit the generated intermediate value to a comparison logic processor placed in the same channel.
In paragraph 6, A reactor protection system using multiple simultaneous logic processors, wherein the number of intermediate values transmitted from the simultaneous logic processor to the comparison logic processor is equal to the number of input signals input to each of the M channels.
In paragraph 5, The generation of the above intermediate value is The values of the input signals of the same item are sorted sequentially, and if two or more of the sequentially sorted input signal values of the same item are the same, a median value is found among the sequentially sorted input signal values of the same item, and a conservative value is obtained from the median value. If two or more of the values of the input signals of the same item sorted in the above sequence are not the same, it is determined whether the number of channels is even; if the number of channels is even, the median value is found excluding the maximum and minimum values from the values of the input signals of the same item sorted in the above sequence, and a conservative value is obtained from the median value. A reactor protection system using multiple simultaneous logic processors, comprising obtaining an intermediate value excluding the maximum and minimum values from the values of the input signals of the same item arranged in the above sequence when the number of channels is odd.
In paragraph 8, Finding the median value among the values of the input signals of the same item sorted in the above sequence, and obtaining a conservative value from the median value A reactor protection system using multiple simultaneous logic processors, comprising removing the maximum and minimum values from the input signals of the same item sorted in the above order, and if duplicate maximum and minimum values exist, removing only the first sorted one, and if the middle value is the same after removing the maximum and minimum values, selecting the first sorted one as the middle value.

Description

Reactor Protection System with Multiple Coincidence Processors The present invention relates to a nuclear reactor protection system, and more specifically, to a nuclear reactor protection system using multiple simultaneous logic processors. FIG. 1 is a drawing for explaining the main configuration of a typical nuclear power plant (100). As shown in FIG. 1, the primary system of the nuclear power plant (100) includes a reactor (130), a pressurizer (140), a coolant pump (150), and a steam generator (160), and the secondary system may include a turbine (170), a generator (180), a condenser (190), and a feedwater pump (191). The reactor (130) raises the temperature of the coolant to about 300 degrees by generating heat of about 1000 degrees Celsius when the nuclear fuel (120) undergoes nuclear fission. In the pressurizer (140), the coolant is applied at a pressure of 160 kg/ cm² in the case of a light water reactor and at a pressure of 110 kg/ cm² in the case of a heavy water reactor so that the water coolant does not boil even at 100 degrees Celsius or higher. The coolant pump (150) performs the function of circulating the primary system coolant, which has come out of the reactor (130) through the steam generator (160), back into the reactor (130). The steam generator (160) performs the function of a boiler in a thermal power plant and, by means of the heated primary system coolant, transfers heat to the feedwater entering through the secondary system condenser (190) and feedwater pump (191), thereby converting the feedwater into steam. The steam generated in this way rotates the turbine (170), and accordingly, the generator (180) converts mechanical energy into electrical energy. While operating such a nuclear power plant, various types of sensors are installed in the reactor system to monitor the integrity of each system, and the status of the nuclear power plant is determined by monitoring detection signals from the sensors. If an anomaly in a system affecting reactor safety or a malfunction in the cooling function within the nuclear steam supply system occurs during the operation of a nuclear power plant, the reactor protection system detects these abnormal conditions to protect the reactor. It then activates the reactor shutdown function via control rod drop and triggers the engineered safety system to cool the reactor. By performing these reactor protection functions, the plant is maintained in a safe state even in the event of an accident, and radiation and radioactive materials are prevented from leaking to the outside. Therefore, as the reactor protection system plays the most critical role in the safety and reliability of nuclear power plants, it must be a system with high reliability and precision to be applied at the plant site; furthermore, under conditions requiring reactor shutdown, the reactor protection system must be capable of performing the function of shutting down the reactor in any environment, both inside and outside the system. To this end, the reactor protection system is generally composed of multiple channels that perform the same function. In addition, the reactor protection system is composed of a signal input unit that acquires detection signals from sensors measuring various process variables and transmits them to multiple channels; a comparison logic unit that compares the acquired detection signals for each process variable with pre-stored setpoints; a simultaneous logic unit that generates a trip signal by combining the outputs of the comparison logic units of multiple channels when the sensor detection signal for each process variable exceeds the setpoint in the comparison logic unit; and a shutdown initiation circuit that drives the reactor shutdown circuit or the operating circuit of the engineered safety equipment according to the shutdown signal output from the simultaneous logic unit. Figures 2a and 2b are functional configuration diagrams to briefly explain the concept of a conventional digital reactor protection system. As illustrated in FIG. 2a, the digital reactor protection system (200) is composed of four channels (Channel A, B, C, D) (211, 212, 213, 214) with a redundancy structure. Although the channels may be composed of four or more, a redundancy structure of four channels is preferred considering the efficiency of redundancy and the complexity of the circuit. The remote shutdown room operator module and the main control room operator module (not shown) are connected to the four channels (211 to 214) to monitor and control the operating status of the reactor protection system. Additionally, the digital reactor protection system (200) consists of a control device and a Man-Machine Interface (MMI) for testing/diagnostics, and an Engineering Work Station (EWS) for initially loading setpoints. The EWS is used to input setpoints and related constants for each processor or hardware within the reactor protection system. The external system consists of a Tr. CPC, a Re