KR20010076544A - ACTM with On-Line diagnosis for CEDMCS in Nuclear Power Plant - Google Patents

Abstract

PURPOSE: A control element drive mechanism control system capable of making an on-line diagnosis in an atomic power station is provided to simplify components of an ACTM, automatize works which were performed in a manual manner and diagnose operation condition of the ACTM on line. CONSTITUTION: A control element control command input/output unit converts a control element control command signal into a TTL level, requests an interrupt to a central process unit, inputs an additional control command by the central process unit, and converts a digital control command and alarm into a CMOS signal. A self diagnosis result output unit outputs a self diagnosis result through the digital control command input unit and provides an error code which is preset. A timer/count unit performs a timer function and a switch watchdog timer function. A coil signal converting unit removes noise in a coil signal processor(206) from a coil current inputted from a CEDM driving coil and converts the same into a digital signal by a predetermined clock and a trigger signal in an A/D converter(209). A program memory(230) collects a diagnosis information according to diagnosis information request and transmits the diagnosis information. The central process unit is operated by an operating frequency and a reset signal, and performs a control program of the program memory to control input/output of the diagnosis information with respect to overall elements. A bus buffer amplifies the control signal of the central process unit. A communicating unit transmits the CTM diagnosis information on a computer screen according to the control signal of the central process unit. A power supplying circuit supplies a power to each element.

Description

Control rod drive automatic controller with on-line diagnosis function in nuclear power plant {ACTM with On-Line diagnosis for CEDMCS in Nuclear Power Plant}

The present invention relates to a control rod drive automatic controller having an on-line diagnostic function in a power control system (PCS) of a nuclear power plant. ).

Reactor output control system (PCS), as shown in Figure 1, is composed of a programmable logic controller (hereinafter referred to as 'PLC') 100, ACTM 200 and DC power controller 300 in hardware.

The PLC 100 executes the most basic functional algorithm of each system, and includes functions required for linkage with an operator. The PLC 100 includes a reactor regulating system (RRS), a control element drive mechanism control system (CEDMCS), and a reactor output derating system, as shown. Power Cutback System (RPCS), Megawatt Demand Setter (MDS) and Load K (Mode K).

When the command to withdraw or insert the control rod from the PLC 100 is input, the ACTM 200 controls the voltage supplied to the drive coil of the control rod drive device CEDM according to a predetermined time sequence, and flows through the drive coil. It is responsible for monitoring the current. In addition, if the withdrawal or insertion command inputted from the PLC 100 is completed according to a normal sequence or an abnormality is found during the execution of the command, the result is reported to the PLC and the next command is waited.

In addition, the DC power controller 300 selectively supplies high voltages, low voltages, and zero voltages required for the mechanical operation of the CEDM by flowing a current through four CEDM coils installed in the control rod driving apparatus according to the control signal of the ACTM 200.

In the conventional ACTM 200 having the above-described peripheral configuration, the card type 8-bit microprocessor is used in the case of the Yeonggwang nuclear power plant, and the 8-bit microprocessor is also used in the case of the System80 + (nuclear power plant) of ABB-CE. Discontinuance of the device is expected by using

In addition, many components, including input-output devices, are complex around the 8-bit microprocessor. Accordingly, when a failure occurs in the ACTM 200, in order to find and repair the cause of the failure, after disconnecting the ACTM from the system, all the input / output states of the ACTM and the operating states of the devices must be checked one by one. There is a problem.

Accordingly, the present invention has one object to simplify the components of the ACTM to solve the above problems, it is also possible to automate the tasks performed manually, and to diagnose the operating state of the ACTM installed in the system online. Has a different purpose.

In order to achieve this purpose, the control rod drive automatic controller with on-line diagnosis function at the nuclear power plant is connected between the programmable logic controller (PLC) and the DC power controller of the reactor power control system (PCS) of the nuclear power plant. The control rod drive (CEDM) drive coil is controlled and inserted for insertion or withdrawal, and the computer on which the diagnostic program is installed is connected to the outside on-line to provide the control and monitoring information on the computer diagnosis screen. According to the present invention, the control rod control command signal from the PLC is converted to the TTL level by the first logic level converting unit, and then the control command signal is combined by the control command input logic unit to the central processing unit if the input is satisfied. Control rod control command input / output means for requesting an interrupt and inputting additional control commands by the central processing unit, converting digital control commands and alarms into CMOS signals at the second logic level converting unit, and performing in a command standby state Self-diagnosis result output means for outputting the self-diagnosis result through the digital control command input means and providing a predetermined error code, and a maximum command execution time timer function for the control command input means according to a clock of a clock generation circuit; Performs the switch watchdog timer function and checks the watchdog timer function at the specified time for the central processing unit A timer / counting means to perform, a coil signal converting means for removing and amplifying a coil current input from the CEDM driving coil by a coil signal processor and converting the signal into a digital signal by a predetermined clock and a trigger signal in an A / D converter; A reset and clock generator that outputs only an operating frequency and a reset signal for operating the central processing unit, and monitors the coil current, performs self-diagnosis, and collects and transmits diagnostic information in response to a request for diagnostic information sent from a computer. A program memory having a control program, an A / D conversion value generated during program execution, a data memory for temporarily storing various data of input / output states of digital control data for insertion or withdrawal of control rods, and an operating frequency or reset signal. Operating by executing the control program of the program memory A central processing unit that controls the input and output of diagnostic information to the child, a bus buffer that amplifies the control signal of the central processing unit, and control of the central processing unit when receiving the diagnostic information request from a computer connected to an external line. And a communication means for transmitting the ACTM diagnostic information to the computer diagnostic screen, and a power supply circuit for supplying constant power to the respective devices.

In the above, the program memory uses 128 Kbytes of EEPROM, and the data memory uses 128 Kbytes of SRAM.

In addition, the CPU can increase the operation processing speed to 20 MHz by using a 16-bit microprocessor.

In addition, the communication means uses an asynchronous serial communication port (RS-232) to connect with a portable computer on-line so that in case of a failure of the ACTM, the cause of failure can be found and coped with promptly.

In addition, the power supply circuit allows a more stable power supply by reducing heat generation by using a DC-DC converter, which generates a lot of heat by using a conventional TTL device.

The power supply circuit operates with a 10V power supply, which is an input power supply of the power supply circuit, compares the voltage divided by the 10V power supply with the output voltage of the power supply circuit, and sends a hold signal to the CPU to stop the operation when it is out of the set value. A power monitoring circuit is added.

1 is a hardware configuration diagram of a reactor output control system (PCS) according to the present invention;

2 is an application example of the present invention,

Figure 3 is a block diagram of the ACTM online diagnostic screen of a computer connected to the present invention,

4 is a block diagram of the present invention,

5 is a complete flow chart for on-line diagnosis of ACTM.

<Explanation of symbols for main parts of drawing>

220: reset and clock generator 230: program memory

240: data memory 250: bus buffer

260: CPU 270: communication port

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

First, the peripheral connection configuration for the on-line diagnosis of the ACTM, as shown in Figure 2 as a whole, the ACTM 200 installed in the system, and the information connected to the ACTM 200 by a serial communication cable and collected from the ACTM A portable computer 400 which is processed and output by a pre-installed diagnostic program, and a monitor 500 which displays information processed by the portable computer 400 on an ACTM online diagnostic screen.

At this time, the information of the diagnostic result transmitted from the ACTM 200, for example, the overall operating status (AC) of the ACTM, the setting status of the various digital input and output devices, the driving coil (UG () obtained through the A / D converter Upper gripper coil (UL), upper lift coil (UL), lower gripper coil (LG), lower lift coil (LL) current values, and the like are displayed on the ACTM online diagnostic screen shown in FIG.

The watchdog timer (WD TMR), interrupt (INT), timer (TIMER), ROM (EEPROM), RAM (SRAM), and A / D converters in the overall status in the ACTM online diagnostic screen shown in FIG. The diagnostic functions of (ADC), INPUT and OUTPUT are functions that existed in the existing ACTM. They are tested once every loop in the command waiting state, and accordingly, the watchdog flag is updated and the timer failure indication when the diagnosis fails. TFA) alarm was generated and operation was stopped. As such, when the diagnosis fails, only the TFA alarm is generated and the operation is stopped. Therefore, it is impossible to know what alarm occurred in the self-diagnosis process, and the diagnosis result can be identified only by installing the test EPROM and checking the output of the diagnosis result.

However, in the ACTM of the present invention, by connecting a computer that provides the diagnostic screen to the RS-232 communication port of the existing ACTM self-diagnosis information, the diagnosis result can be immediately checked during the operation of the ACTM, and a more detailed operation state is shown. It provides digital input, digital output and A / D conversion results together.

Next, the internal configuration and operation of the ACTM 200 for on-line diagnosis of the present invention will be described with reference to FIG. 4.

First, the configuration of the ACTM 200 includes a combination of a first logic level converter 201 for converting a control rod control command signal (CMOS signal), which is data from an upper circuit, to a TTL signal, and the converted control rod control command signal. A control command input logic unit 202 for requesting an interrupt (INT) from the central processing unit 260, a clock generation circuit 203 for generating a 10 KHz reference clock required for the operation of the timer counting circuit, The clock generation circuit 203 operates by the clock generated to check the watchdog timer function (WD) at every predetermined time (WD), perform the S / W watchdog timer function (SFDG), and execute the maximum instruction. A timer / count circuit 204 for setting the in-cycle time (CT), a digital control command input unit 205 for inputting control rod control commands from the initial value and the upper circuit by the microprocessor, and a sensor detected using the sensor 4 CEDM A coil signal processor 206 for removing noise included in the analog current signals of the driving coils UG, UL, LG, and LL and amplifying the signals, and a 500 KHz oscillator 207 for generating a clock required for an A / D conversion operation. ) And from the coil signal processor 206 in accordance with the operation of the oscillator 207 and the auto trigger 208 to output a trigger signal to automatically perform an A / D conversion operation every 500 ms. A / D converter 209 for converting the input coil current signal into a digital signal, a power supply circuit 210 for supplying the required voltage to the TTL element using a DC-DC converter, and whether power is constantly supplied. A power supply monitoring circuit 211 for monitoring a digital signal, a digital control command and alarm output unit 212 for outputting a digital control command and an alarm signal, and a TTL signal output from the control command and alarm output unit 212 as a CMOS signal. Second logical array to convert The conversion unit 213 and the self-diagnosis result performed in the command standby state are output as 8-bit binary through the digital control command input unit 205 and provided with a predetermined error code by two 7-segment LEDs installed on the front of the ACTM. A diagnostic result output unit 214, a reset and clock generator 220 for outputting a reset signal and a clock of 20 MHz necessary for operation of the CPU 260, and a program memory 230 for storing an ACTM control program in the form of an executable file. ) And a data memory 240 for temporarily storing various data (A / D conversion value, flag, digital input / output data, diagnosis result output state) generated during program execution, and the output of the reset and clock generator 220. 16-bit CPU which controls input / output of information stored in data memory 240 by executing control program of ACTM stored in program memory 230 according to reset signal and clock Microprocessor 260, microprocessor 260, timer / count circuit 204, digital control command input unit 205, A / D converter 209, digital control command and alarm output unit 212, program The memory 230 and the data memory 240 are connected to a bus, respectively, and a bus buffer 250 for amplifying and outputting a new signal inputted and outputted through the bus, and the bus buffer 250 and an external device having a diagnostic program installed thereon. An asynchronous serial communication port (RS-232) 270 connected between the portable computers 400 to serially transmit ACT self-diagnosis results and operation information required for the ACTM online diagnosis screen configuration (see FIG. 3) of the monitor 500. It consists of).

In the above, the power monitoring circuit 211 is composed of a comparator, and operates with a 10V power source that is an input power supply of the power supply circuit, and compares the voltage obtained by dividing the 10V power supply with the output voltage of the power supply circuit to deviate from the set value. Hold signal is sent to CPU to stop the operation.

In addition, the diagnostic result output unit 214 displays the overall status information in the form of a predefined number among all the diagnostic information displayed on the diagnosis screen on the computer through two seven segments installed on the ACTM front panel. At this time, the diagnosis result output unit 214 is a screen form that can be easily identified by using the communication function in the normal control operation state of the ACTM when using a computer, together with the self-diagnosis result and the state of each input / output device and the A / D converter ( It is possible to check the CEDM coil current and ACTM operating voltage input to each channel of 209).

In the above, the program memory 230 can be updated by downloading an ACTM program using a communication function by using a 128 Kbyte EEPROM. The data memory 240 uses 128 Kbyte SRAM.

In addition, the central processing unit 260 has conventionally used an 8-bit microprocessor, but in the present invention, by using a 16-bit microprocessor, the operation processing speed is increased to 20 MHz.

Referring to FIG. 3 and FIG. 4 and FIG. 5 which shows the diagnostic program installed in the portable computer and the control program of the ACTM stored in the program memory 230 of the ACTM, the ACTM online diagnosis process of the present invention will be described as follows.

After the portable computer is connected to the asynchronous serial communication port 270 through a serial cable, the diagnostic program installed in the computer and the ACTM program are started to correlate with each other to execute an online diagnosis of the ACTM as shown in FIG. 5.

According to the on-line diagnosis of the ACTM, when the diagnostic program installed in the computer connected to the ACTM is executed, the computer provides the diagnosis screen shown in FIG. 3 to the monitor (S1). Subsequently, the diagnostic program initializes RS-232 communication by setting a communication speed and the like so that the serial communication port 270 can communicate with the ACTM in the computer (S2). After initialization, the ACTM requests information for updating the diagnosis screen through the RS-232 communication port 270 (S3).

On the other hand, when power is supplied to the ACTM, the reset and clock generator 222 sends a reset signal to the microprocessor 260 to start a control program stored in the program memory 230 of the ACTM. In the microprocessor 260, a timer / count circuit 204 connected to the bus via a bus buffer 250, a data memory 240, an RS-232 serial communication port 270, a digital control command input unit 205 and digital control Initializes the command and alarm output unit 212 (S11). After initialization, the A / D converter 209 which receives the coil current input from the CEDM driving coil to the coil signal processor 206 converts the coil current value of the digital signal into a temporary value in the bus buffer 250 and the data memory 240. Send it for storage. At this time, the microprocessor 260 monitors the current value flowing in the drive coil of the converted control rod drive device and sends the control signal to the digital control command and the alarm output unit 212 according to the control rod control command data input to the digital control command input unit 205. In response to the control command and the alarm signal inputted and outputted, the self-diagnosis of the ACTM is performed (S12).

The portable computer requests diagnostic information for updating the diagnostic screen from the ACTM (S3). In the ACTM, if the request command is received while the control command is waiting and the command is executed (S13), an interrupt is generated and the command is interpreted (S14). When the diagnostic information is requested, the ACTM collects diagnostic information, for example, overall status information, digital inputs, digital outputs, and A / D conversion results (S15). After transmission (S16), the signal returns to before the interrupt occurs. However, as a result of command interpretation (S14), if it is a control command, the ACTM performs the control command under the control of the microprocessor (S17), monitors the coil current again, and performs self-diagnosis (S12).

When the computer receives the diagnostic information from the ACTM (S4), the diagnostic information is interpreted to update the ACTM online diagnosis screen (S5), and then waited for input of a button displayed on the diagnosis screen (S6). After interpreting the input of (S7), press the 'Recheck' button to request new information from the ACTM to update the screen content according to the received information. And press the 'Exit' button to end the diagnostic work, and remove the serial communication cable connected to the RS-232 serial communication port (270).

This online diagnosis of ACTM is always possible by connecting a serial cable between the serial communication port and a portable computer, regardless of the ACTM operating status.

In the control rod drive automatic controller (ACTM) for the on-line diagnostic function of the present invention as described above, the operating state of the ACTM is frequently operated by the driver through the diagnosis screen of the result of performing the diagnosis program of the ACTM through a computer connected to the device online In case of failure, it provides diagnostic information on the operating status in ACTM so that the cause of failure can be easily found. Thus, the effect of quickly and accurately performing troubleshooting of ACTM is obtained.

Claims (7)

Connected between programmable logic controller (PLC) and DC power controller among nuclear reactor power control system (PCS) of nuclear power plant, control and monitor the control rod drive device (CEDM) drive coil to insert or withdraw the control rod, and the diagnostic program is installed. In order to connect the computer to the outside online and provide the control and monitoring information on the computer diagnostic screen, After the control rod control command signal from the PLC is converted to the TTL level by the first logic level converting unit 201, the control command input logic unit 202 combines the control command signal to interrupt the central processing unit when the input is satisfied. A control rod control command input / output means for requesting a signal, inputting an additional control command by the central processing unit, and converting the digital control command and the alarm into a CMOS signal by the second logic level converter 213; Self-diagnosis result output means for outputting a self-diagnosis result performed in a command waiting state via the digital control command input means and providing a predetermined error code; A timer that performs a maximum command execution time timer function and a switch watchdog timer function for the control command input means according to the clock of the clock generation circuit 203, and checks the watchdog timer function at a predetermined time for the central processing unit. Counting means; Coil signal conversion means for converting a coil current input from the CEDM driving coil into a digital signal by removing a noise from a coil signal processor 206 and amplifying the A / D converter 209 by a predetermined clock and a trigger signal; A reset and clock generator for outputting a clock and reset signal for operating the central processing unit; A program memory for monitoring the coil current, performing self-diagnosis, and having a control program of ACTM for collecting and transmitting diagnostic information in response to a request for diagnostic information transmitted from the computer; A data memory for temporarily storing various data of the A / D conversion value generated during the program execution and the input / output state of the digital control data for insertion or withdrawal of the control rod; A central processing unit operated by the operating frequency or a reset signal and controlling input / output of diagnostic information for all devices by executing a control program of the program memory; A bus buffer for amplifying the control signal of the central processing unit; Communication means for transmitting the ACTM diagnostic information to a computer diagnostic screen according to the control of the central processing unit when receiving a request for diagnostic information from a computer connected on-line to the outside; And It is composed of a power supply circuit for supplying power to each of the elements, it provides a necessary information to easily find the cause of the failure in the event of a failure of the ACTM drive rod having a function of on-line diagnosis in the nuclear power plant Device auto controller. The method of claim 1, The program memory, Control rod drive automatic controller with on-line diagnosis function in nuclear power plant, characterized by using 128Kbyte EEPROM which can be controlled by communication. The method of claim 1, The data memory, Control rod drive automatic controller with on-line diagnosis function in nuclear power plant characterized by using 128Kbyte SRAM. The method of claim 1, The central processing unit, A control rod drive automatic controller with on-line diagnostics at a nuclear power plant, characterized by improved operation speed using a 16-bit microprocessor. The method of claim 1, The communication means, Control rod drive automatic controller with on-line diagnosis function in a nuclear power plant characterized by using asynchronous serial communication port (RS-232). The method of claim 1, The power supply circuit, Control rod drive automatic controller with on-line diagnosis function in a nuclear power plant characterized in that the use of a DC-DC converter. The method of claim 1, The power supply circuit further includes a power monitoring circuit for comparing the voltage divided by the voltage input to the power supply circuit with the output voltage of the voltage supply circuit to stop the power supply to the central processing unit when the setting value is out of the set value. Control rod drive automatic controller having an on-line diagnosis function in a nuclear power plant, characterized in that.