KR100262354B1 - Detection apparatus and method for dc power source grounding - Google Patents

Abstract

PURPOSE: A DC power ground detecting apparatus is provided to be capable of detecting the existence of a ground by checking a plurality of points of contact in a short time. CONSTITUTION: The fourth connector(27-4) interconnects an interface unit so as to be extended, and the third connector(27-3) is connected to a data conversion box. The first connector(27-1) makes a sensor(10) for detecting a ground to be connected to eight channels. A central processing unit(21) receives a detection signal through the first connector(27-1) and converts the received detection signal through an amplifier(25) and an analog-to-digital converter(21-1). An address controller(22) directs the central processing unit(21) so as to be operated. An amplifier(24-1) amplifies scanning data of the central processing unit(21) to apply the amplified scanning data to the data conversion box through the third connector(27-3). The second connector(27-2) interconnects the central processing unit(21) and the amplifier(24-1).

Description

DC power ground detection device and method

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a DC power ground detection device, and more particularly, to a data conversion box for connecting a DC power supply used as a control power supply of a power generation facility to a computer main body, and to a conversion box and detecting several grounds at a predetermined distance. The interface unit with the sensor has a basic configuration, and the ground detection sensor allows the computer to recognize whether or not it is grounded, and if there is a problem with the interface unit itself, the DC power ground for skipping it and recognizing data from other interface units. A detection apparatus and method are provided.

In general, both the positive and negative DC voltages used as the control power supply of power generation facilities are floating. However, when the control power supply (for example, DC power supply 250 volts) or more, the control equipment is tripped and the energy is not supplied, and the equipment completely stops functioning. In consideration of this importance, the control power is normally operated by the charger, but in the event of power failure of the power plant, the control power is supplied by the voltage charged in the battery. In this case, the positive and negative grounds are continuously monitored to ensure the soundness of the control power supply. Therefore, if the positive power is grounded and negative at the same time, the control circuit is short-circuited and the power is lost. The control system is then tripped, often causing the entire power plant to trip. These accidents should be restrained in advance because they are caused by unexpected accidents. To this end, a DC power ground detection device was developed and used. As shown in FIG. 1, a switch 3 was added to the main power rectifier 1 and the control power load stage 2 of the power plant. The rectifier 4 is connected in common. In addition, the switch 3-1 which acts on and off as opposed to the switch 3 is added to the test rectifier 4 and the control power load stage 2. When the load disconnect switch 3 of the main rectifier 1 is cut off in such a parallel operation state, power is supplied from the test rectifier 4 to the load stage 2, and at this time, the ground detection attached to the test rectifier 4 is detected. Circuitry (not shown) checks grounding status for that branch load. If there is no ground state at the branch load stage, the grounding alarm does not occur at the test rectifier 4, and if the branch load stage is grounded, an alarm means (not shown) is generated at the test rectifier 4 to ground the branch. You must find This ground detection method does not operate the breaker (switch) according to the correct procedure, the loss of the control power to the branch load stage (2) of the control power supply, the logic sequence is zero, tripping the load breaker, There is a problem of stopping the operation of the valve. In addition, the existing detection method should detect by branch number by manipulating artificial test rectifier and check the control power of each facility by using ground detector for branch load in ground state. However, the point of contact required to control power generation facilities is about 100,000 points for nuclear power, about half the thermal power, and about 20,000 points for general industrial plants. In other words, the contact point changes frequently depending on the operating state of the power plant. This point indicates that even if the power plant is completely grounded when the power plant is stopped, the point of the contact point changes when the power plant is in operation. In some cases, the control line is changed to cause an alarm of ground again. In other words, it is almost impossible to completely remove it, and there is always some degree in the control facility, but it is a common phenomenon that the degree of grounding becomes serious in the summer rainy season during the rainy season. Specifically, when the grounding of the control power supply trips the facility, the control power source is 250 DC power source. As shown in FIG. 2, the control power source is a floating state in which neither the positive plus or minus ground is grounded. The state as shown in FIG. 2 is a line state of the control power supply in which soundness is ensured as a normal state. However, if one of the lines in the line is grounded due to leaks and defects in the insulation of the equipment, a closed loop as shown in Figure 3 is achieved. As such, the closed circuit of the thin solid line due to the ground shorts the load of the control power of the equipment and blows out the protective fuse so that the equipment is tripped due to the loss of the control power. In the conventional ground detection method, the voltage of the plus or minus line is changed based on the ground according to the ground state. For example, if the minus is a little grounded, the voltage on the plus line is a +50 volt dc power supply. The difference between these voltages causes the electronic circuit card to compare voltages with each other to generate an alarm. At this time, the sensing of voltage changes in inverse proportion to the resistance according to the ground state of the line. When grounded with less resistance, the negative voltage of the control supply would be zero volts equal to the ground level, and the plus would be a +250 volt DC supply. This condition is that one line is fully grounded, so if the other plus line is grounded, the protective fuse is blown because a large current flows.

An object of the present invention is to solve this problem, the grounding of the DC power used as a control power supply of the power generation equipment through a plurality of Hall elements and stored in the interface unit and then the signal to the computer body through the data conversion box The main unit is to check whether there is an abnormality, and the interface unit can be extended to a desired number so that a plurality of inspection points can be accurately checked in a short time to detect the grounding.

To this end, the present invention is essential configuration of a data conversion box for connecting the printer port and the serial port of the computer main body, and an interface unit that can be extended by a certain distance from the data conversion box and stores data from several Hall elements. Consists of elements.

1 is a configuration diagram showing an example of a technique for detecting a conventional ground.

2 is an explanatory diagram showing an example of a DC power supply.

3 is a diagram of a DC power supply structure showing a state of being grounded to the power supply of FIG.

Figure 4 is a block diagram of a Hall element used in the present invention for detecting whether or not grounding.

5 is a view for explaining the principle of the magnetic field induced in the Hall element used in the present invention.

6 is an overall configuration diagram of the present invention.

7 is a schematic diagram showing data transmission between the data conversion box and the interface unit of the present invention.

8 is a block diagram illustrating the entire apparatus of the present invention.

9 is a configuration diagram showing a wiring relationship between a data conversion box and an interface unit of the present invention.

10 is a connection diagram showing the relationship between the data conversion unit and the connection port of the computer main body of the present invention.

11 is a configuration diagram of an interface unit showing a data transmission port and a sensor channel port of the interface unit of the present invention.

12 is a flowchart of the present invention.

FIG. 13 is a flowchart embodying a process for instructing to find the interface of FIG. 12. FIG.

14 is a flowchart showing the scanning process of FIG.

* Explanation of symbols for main parts of the drawings

1: main rectifier 2: load stage

3, 3-1: switch 4: test rectifier

5: ferrite core 6, 6-1: cable

7: Hall element 8: Amplifier

10: element for detection 20: interface unit

21: central processing unit 21-1: analog digital converter

22: address controller 22-1: relay

22-2: dip switch 23: reset detection unit

24: connection portion 25: amplifier

26: RAM 27: ROM

27-1 ~ 27-4: Connector 30: Data conversion box

31-1: Buffer 32: Reset Button

33, 34: data amplifier 40: main body

41: printer port 42: serial port

That is, the present invention provides a personal computer main body which designates unique addresses for a plurality of interface units and analyzes detection data through each interface unit; A data conversion box provided around the main body to receive address data through a printer port of the computer main body and to transmit and receive data through a serial port; An interface unit connected to the data conversion box by a predetermined distance and accommodating several DC power ground detecting sensors; The interface unit is provided with a plurality of DC power supply ground detection device characterized in that the sharing port to the data conversion box is made to use a plurality of extensions.

In addition, the present invention provides a process of assigning a unique number to a plurality of interface units, a command to find a corresponding interface unit, a process of scanning detection data of elements assigned to the interface unit for each channel, and a reference value for each channel. It is to provide a DC power ground detection method characterized in that the process of comparing with, and if there is an alarm and displays the result if it is normal, and finds the next interface unit and repeats the process to the last interface unit. . The present invention obtains data on whether or not the ground of the set location through the Hall element, which is a ground detection sensor, which is analyzed in the computer main body through the data conversion box, and the interface unit is given a unique address of the main body according to the instructions of the main body. It scans the data of the corresponding interface unit, and if there is no command, it blocks the interface unit from the data conversion box and contributes to the data transfer from the corresponding interface unit. Therefore, even if a part of the interface unit fails, the remaining interface unit is checked. Makes it possible.

Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

4 is a configuration principle of the Hall element used in the present invention. The cable 6 receiving the input power is placed in the center of the ferrite core 5 and the Hall element 7 is placed in the middle of the ferrite core 5. Settled down, the output of the hall element 7 is output via the amplifier 8. The size and direction of the magnetic flux is determined by the magnitude of the current generated in the cable 6 according to the right-hand screw law of ampere. In other words, the positive current and the negative current received through the cable 6 are negative. If the current value is the same, there is no magnetic flux. However, if a small current difference occurs, there is a difference between the current due to the positive voltage and the current due to the negative voltage since it is already grounded. In the grounded state, the Hall element 7 detects a magnetic flux as a voltage for a difference of small microcurrents (tens of several hundreds of amperes in advance). The magnetic field generated by the right screw law of ampere in the direction of the arrow generated by the current through the cable 6 is applied to the Hall element 7 through the ferrite core 5 as shown in FIG. (8) to amplify.

6 is an overall configuration diagram of the present invention, in which a plurality of interface units 20 in which several ground detecting sensors 10 including the hall elements 7 are installed in the main rectifier 1 and the control power supply load stage 2. And a print port of the computer main body 40 that transmits and receives data through the cable 6-1, which is hundreds of meters long, connected to the interface unit 20 and the data conversion box 30, and the cable 6-1. And a data conversion box 30 connected to the serial port, and a computer body 40 that exchanges data with the data conversion box 30 and performs data analysis and instructions.

FIG. 7 is an explanatory diagram showing a configuration in which the data conversion box 30 and the interface unit 20 of the present invention exchange data through the cable 6-1. Amplification of one line of data via the serial port COM1 is applied to the central processing unit 21 of the interface unit 20, the other line sends the collected data back, and parallel through the print port LPT1. Data is converted into serial data by the parallel serial converter 31 and applied to the address controller 22 through one line, and the reset button 32 of the reset function is supplied to the reset detection unit 23 of the central processing unit 21. One line is applied, and the other is the round line. That is, five lines are implemented.

8 is a configuration diagram showing an example of use of the present invention, which includes a data conversion box 30 around the computer main body 40, and can be installed and used at a distance of about 500 meters from the data conversion box 30 ( 20) with the cable (6-1). The interface unit 20 places about eight DC power ground detecting sensors 10 in a DC power cable.

9 is a block diagram showing the present invention in a block state, comprising: a personal computer main body 40 which designates unique addresses for each of the plurality of interface units 20 and analyzes detection data through each interface unit 20; A data conversion box 30 provided around the main body to receive address data through a printer port of the computer main body 40 and to transmit and receive data through a serial port; The interface unit 20 is connected to the data conversion box 30 and a cable 6-1 of a predetermined distance and accommodates several DC power ground detecting sensors 10. The interface unit 20 is A plurality of devices are provided to share the connection part 24 with the data conversion box 30, and a plurality of extension parts are provided by sharing the connection part 24 with the data conversion box 30.

The data conversion box 30 has a parallel serial converter 31 for converting parallel data through the printer port 41 into serial data, a serial converter 31 output and the serial output through the serial port 42 at a distance. Data amplifiers 33 and 34 which amplify to be transportable.

The data conversion box 30 is added with a reset switch 32 for resetting the function of the interface unit. The interface unit 20 receives an output of several DC power supply sensors 10 and amplifies the amplifier 25 and converts the amplification values of the respective amplifiers 25 into digital data. Comparing the address designation value through the data conversion box 30 with the setting value and controlling the designation interface unit 20 selection relay 22-1 to be turned on and off. And an address controller 22.

The central processing unit 21 is a one-chip microprocessor, controlled by the RAM 26 storing the scanning data of the DC power ground detecting sensor 10 and the ROM 27 storing the scanning command program. Is done. The unique address of the address controller 22 is implemented by the dip switch 22-2, which is advantageous in cost reduction.

FIG. 10 is a block diagram showing the connection data bus of the computer main body 40 and the data conversion box 30 of FIG. 9, wherein the serial port 42 has a data amplifier 34 and the parallel (print) port 41 has a parallel. The serial converter 31 is connected, and the printer shaft 41 and the converter 31 allow data to be temporarily exchanged through the buffer 31-1.

FIG. 11 is a block diagram showing the interconnection structure of the interface unit 20 of the present invention. The fourth connector 27-4, which extends the interface unit 20 to each other, and the data conversion box 30, The third connector 27-3 to be connected, the first connector 27-1 enabling the ground detection sensor 10 to be connected to up to eight channels, and the detection signal are provided through the first connector 27-1. A central processing unit 21 which is applied and converted through the amplifier 25 and the analog digital converter 21-1, and then controls; an address controller 22 which commands the central processing unit 21 to operate; An amplifier 24-1 for amplifying the scanning data of the apparatus 21 and applying it to the data conversion box 30 through the third connector 27-3, and the central processing unit 21 and the amplifier 24-1. ) Is made up of a second connector 27-2. The third and fourth connectors 27-3 and 27-4 and the amplifier 24-1 form a connection part 24.

The present invention thus constructed will be described with the flowchart of FIG.

That is, a process of assigning a unique number to a plurality of interface units (100), a process of instructing to find a corresponding interface unit (110), and a process of scanning detection data of elements assigned to the interface unit for each channel (120). And, the process of comparing the reference value for each channel (130), and if there is an alarm and displays the result if it is normal (140), find the next interface unit (150) and repeat the process to the last interface unit Perform 160.

13 and 14 are more specific flowcharts of FIG. 12, which store the entire program for carrying out the present invention in the computer main body 40, and preset the recognition address data corresponding to the interface unit 20 ( Step 100), and then, when a detection command comes through the keyboard (not shown) of the main body 40, a program for performing this is operated (step 110). Subsequently, the scanning process 120 is performed. The scanning process first applies a desired address through the printer port 41 according to the procedure (e.g., parallel 8 bits), and converts the parallel data into serial data (in the parallel serial converter 31) and transmits it (step 111). ). In this case, the data amplifier 33 amplifies and transmits the data, and the cable 6-1 is about 500 meters in length, and thus amplifies and transmits the data in consideration of line loss, etc. The amplified address data is transmitted by the address controller 22. The unique dip switch 22-2 is compared to match the unique address recognized (step 112), if it is matched, the relay 22-1 shown in Fig. 9 is turned on (step 113). After delaying (step 114), the central processing unit 21 is driven and then commanded to read the data of the detection sensor 10 (fixed 115), which is a ROM 27 inside the interface unit 20. Then, the CPU 21 commands the central processing unit 21 to store the scanning data in the RAM 26 (step 116). Then, when the saving is completed, the scanning data is instructed by the ROM 27 command. Convert (E.g., eight 8-bit data) (step 117), and then through the serial port 42, the main body 40 compares it with a setting reference value and sounds an alarm if it is smaller than the reference value (process). 131), if it is large, the value is displayed on the monitor (step 140.) At this time, if it is determined that the interface unit 20 has an error, the reset button 32 is turned on manually or automatically to operate only the error unit 20. If the search for one unit is completed, address data is increased by one (step 150), but if the increased value is not the final address (step 160), the address controller is turned off. The relay is turned off (step 161), and if the last address is repeated, step 110. If step 161 is followed by a delay of, for example, 10 milliseconds (step 162), step 112 is performed. Number And. The ever-specific address of the interface, in step 112 (e. G. 7) is not the comparison with the unique address of the other interface unit, and (process 118) when performing the matching process 113. If there is also a mismatch in the process 118, it is compared with the unique address of another interface unit (119). This comparison process is repeated, for example, up to the total number of installations (eg 256).

As described above, the present invention installs a ground detection sensor based on a Hall element at a desired measuring point so that the data obtained therefrom is scanned at a central processing unit at a time and applied to the data conversion box 30 so as to confirm. Accurate and quick detection is easy. In addition, since the detection device is implemented using the existing computer main body, the equipment cost can be reduced. In addition, since the interface unit is assigned a corresponding address by using a dip switch, the interface unit can be provided at such a low cost without a separate address designation means. In addition, since the data converter transmits and receives data through an amplifier, it is possible to overcome the distortion caused by the length of the cable by overcoming the distortion of the signal due to the length of the cable. In addition, since the interface unit has two ports to be connected to other interface units in addition to the data conversion box 30 by using a connection part, even a control circuit part distributed in a wide space using a predetermined cable can be conveniently installed.

Claims (1)

A personal computer main body for assigning a unique address for each of the plurality of interface units and analyzing the detection data through each interface unit; A data conversion box provided around the main body to receive address data through a printer port of the computer main body and to transmit and receive data through a serial port; An interface unit is connected to the data conversion box by a certain distance and includes several DC power ground detecting sensors. The interface unit is a fourth connector (27-27) which extends and interconnects each interface unit. 4), a third connector 27-3 connected to the data conversion box 30, a first connector 27-1 for enabling connection of the ground detection sensor 10 to 8 channels, and a first connection. The central processing unit 21 and the central processing unit 21 for receiving the detection signal through the connector 27-1, converting and controlling the amplifier 25 and the analog digital converter 21-1, and then operating the same. An amplifier 24-1 which amplifies the command address controller 22, the scanning data of the central processing unit 21, and applies it to the data conversion box 30 through the third connector 27-3; Second connector connecting the processing unit 21 and the amplifier 24-1 DC power supply ground detection apparatus, characterized by made of an (27-2).

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