KR200344922Y1 - Composite protective relay device - Google Patents

Abstract

The present invention relates to a complex relay device, comprising a central processing unit for performing a protection algorithm with a signal from a digital signal processing processor for processing a data from the output side of the power detection unit to detect a failure to perform the protection algorithm, A backup memory unit connected to the central processing unit for backing up the correction values of each relay element, and a communication module connected to the central processing unit for transmitting fault information to the central monitoring unit in case of a fault detection, and some relays depending on the protection target. Dip switch setting unit for selecting to perform only the element function, a button switch input unit for allowing the user to correct various correction values for each relay element, and for displaying the various correction values and the electric power input to the current switchboard In the composite relay device comprising a display unit, the primary side of the current converter, A short circuit detection unit connected to the primary side of the piezoelectric transducer, and a dual port memory for storing data in the digital signal processor and the dip switch setting unit, wherein the short circuit detection unit determines whether or not the short circuit is detected in advance. It can be configured to protect the power consumer by cutting off the power regardless of the abnormality of the power supply. It was.

Description

Composite relay device {Composite protective relay device}

The present invention relates to a composite relay device, and more particularly, to a composite relay device for performing a complex monitoring and protection function for the switchboard power by integrating the relays separately separated into one device.

In general, in order to protect various electric devices operated in a power consumer and to control a control device such as a circuit breaker and a switch, a relay device for detecting various failures occurring in the switchboard and performing a protection function is required.

As described above, the relay device senses various electric quantities (voltage, current, zero phase current, zero phase voltage, frequency, etc.) of the switchboard and compares the values of quantitative and electrical phases with each other in comparison with normal operation values. It is a device that performs the control function to operate various breakers or switchgear to separate the protection object from the power source when it is out of the predetermined standard value. Most factories, buildings, In public buildings, switchboards with relay devices are installed.

1 shows a digital switchboard according to the prior art, and an overcurrent relay for detecting and protecting current from distribution lines R phase, S phase, and T phase using respective current transformers (CT_R, CT_S, CT_T). (Over Current Relay: OCR_R, OCR_S, OCR_T) (5,5 ', 5) and ground fault (Ø) to detect ground fault using ground current (Ø) as the input electric current and ground fault to perform ground fault protection function for the ground distribution system. Over Current Relay (OCGR) (6) and Over Voltage Relay (OVR) (1) and Under Voltage Relay (1) to detect and protect the line voltage appearing on the distribution line. UVR) (2) and Zero Current Transformer (ZCT) (8) to detect the image current generated when a ground fault occurs on the distribution line of the three phases, and detect the ground current voltage to detect the image current magnitude, image voltage magnitude and Phase difference between them Is a ground fault overvoltage relay for detecting ground fault and inputting the ground fault protection function for the non-grounded distribution system. Over Voltage Ground Relay: OVGR) (4) is connected independently to control AC breaker / contactor (7).

When the operation of each of the relays described in more detail, the overcurrent relays (OCR_R, OCR_S, OCR_T) (5, 5 ', 5) respectively detects the current flowing through the distribution line and the AC blocking / An operation command is given to the contactor 7, and the ground fault over current relay (OCGR) 6 is a ground fault over current relay for protecting the ground distribution system. The operation signal to the contactor (7), and the overvoltage relay (OVR) 1 and the undervoltage relay (UVR) 2 respectively sense the voltage of the distribution line and the AC disconnection / contactor if it is larger or smaller than the normal value. In operation (7), the ground fault overvoltage relay (OVGR) 4 senses an image voltage obtained from a vector sum of voltages of three phases in the case of the non-grounded power distribution system and exceeds a predetermined reference value. Determining a failure and giving an operation signal to the AC disconnection / contactor 7, the directional selective ground relay (SGR) (3) is to selectively determine the failure only in the case of a sub-line failure when a ground fault occurs in the non-grounded distribution system As the relay element, the image current is sensed through the secondary side of the current transformer (ZCT) (8), and the image voltage is sensed in the same way as the ground fault overvoltage relay (OVGR) (4). When the magnitudes of the image current and the projection voltage are equal to or larger than the reference value and the phase difference between them is within the correction range, it is determined as an auto circuit failure and an operation command is given to the AC disconnection / contactor 7.

In the conventional digital switchgear configuration, since each of the single type relays must independently perform a protection function, as shown in FIG. 2, each of the relays has a unique signal detection unit 20 and an appropriate signal before analog / digital conversion. An input signal converter 30 for converting an input analog signal to a level, a central processing unit 40 for performing a protection algorithm using a value converted into a digital signal through an analog / digital converter, and a correction value and a measured value. Display unit 50 for displaying and an external circuit breaker circuit at the time of fault detection

It has a contact output unit 60 for outputting the contact signal, and the independent relays having such an internal configuration are installed in the switchboard for each relay element required according to the protection needs.

However, in the conventional relay apparatus as described above, since each relay is installed on the switchboard for each relay element as described above and operates independently of each other, the installation cost increases and each relay installed at one protection point of the switchboard is the same. It is very difficult to perform the optimal protection function because the protection method is different or the contact method is different, so it is difficult to perform the optimal protection function. Also, in order to operate the relays with the central monitor, the communication method is different. There have been many problems, such as the need to add a separate communication option.

Therefore, the present invention integrates the protection function of the main protection relay applied to the existing switchboard and solves the problems as described above, and performs the complex monitoring and protection function for the switchboard power by implementing the digital method, and the reliability of the protection function. It is to provide a composite relay device that can improve the.

Another object of the present invention is to provide a composite relay device characterized in that the short-circuit detection unit in the composite relay device to determine the short circuit in advance to protect the load side by cutting off the power regardless of whether or not the central processing unit is abnormal. To provide.

1 is a structural diagram showing the configuration of a digital switchboard according to the prior art;

2 is a structural diagram showing the configuration of a relay device according to the prior art;

3 is a detailed structural diagram of a composite relay device according to the present invention,

4 is an external configuration diagram of a composite relay device according to the present invention, and

5 is a functional block diagram of a short circuit detection unit according to the present invention.

<Description of the symbols for the main parts of the drawings>

100: complex relay device 101: input conversion unit

102: low pass filter 103: multiplexer

104: analog to digital converter 105: digital signal processor (DSP)

106: dip switch setting unit 107: dual port memory (DPRAM)

108: central processing unit 109: random access memory (ROM)

110: backup memory 111: display unit

112: communication module 113: contact signal output unit

130: short circuit detection unit

131: memory 132: arithmetic circuit

133a: Sample Hold A (SH) 133b: Sample Hold B (SH)

134: multiplexer (MU) 135: A / D converter

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

Figure 3 is a schematic block diagram of a composite relay device according to the present invention, the composite relay device 100 is the three-phase current (IR, IS, IT) and the image current (IØ), image voltage (VØ) and voltage An input converter 101 for converting a signal range for processing by the analog / digital converter 104 inside the central processing unit 108 to be described later as VRS and VST, and signal sampling To remove high frequency signals from the outputs VRS ', VST', VØ ', IR', IS ', IT', and IØ 'of the input converter 101 to prevent aliasing. A low pass filter 102 and a multiplexer 103 for supplying the output of the low pass filter 102 to the analog-to-digital converter 104 in the central processing unit 108 in one channel according to a channel control signal; The small signal region of the output signal of the multiplexer 103 is amplified and inverted according to the gain control signal to add the signal. A digital signal processor (DSP) 105 for detecting a failure from the output of the tip multiplexer 103 and processing it into data capable of performing a protection algorithm and converting the data into an analog value in the analog / digital converter 104. And a central processing unit 108 for detecting a fault from the digital value and performing a protection algorithm, connected to the central processing unit 108 by a data bus, and displaying the various correction values and various electric amounts input to the current switchboard. And a backup memory unit 110 connected to the central processing unit to back up the correction values of the relay elements.

The communication module 112 is connected to the central processing unit 108 and transmits the failure information to the central monitor when the failure is determined. The digital signal processing processor (DSP) 105 and the following dips are used. Short circuit connected to the primary side of the dual port memory (Dp ram) 107 and the current transformers CT_R, CT_S, CT_T, which store the data of the positioning unit 106, and the primary side of the voltage converters PT_RS, PT_ST. The detection unit 130 and a dip switch setting unit 106 for using only a part of all the relay elements according to the protection target are used.

4 is a block diagram showing a remote control via the communication module 112 of the multi-component relay device. In the communication module 112, a fault phase in the order of fault occurrence time at the time of the fault detection in the processing unit, It saves the fault type and fault data and transmits the information to the central monitoring board to facilitate remote control and to make up to 255 network configurations.

FIG. 5 is a schematic functional block diagram of the short circuit detecting unit 130. The short circuit detecting unit 130 collects voltage information of a sample hold A (SH, 133a) for collecting current information of a current converter and a voltage converter. Sample hold B (SH, 133b), a multiplexer (MU ', 134) for multiprocessing the collected information, and an A / D converter (135) for converting the output signal of the multiplexer (MUX, 134) into a digital signal. ) And a memory 131 for storing the above-mentioned converted signal, and a calculation circuit 132. for calculating whether to short-circuit through the current and voltage data immediately before the failure occurs.

The fault detection according to the short circuit detection unit 130 of the present invention configured as described above will be described in detail.

The primary side current information of the current converters CT_R, CT_S and CT_T and the primary side voltage information of the voltage converters PT_RS and PT_ST are respectively stored in the sample hold A (SH, 133a) and the sample hold B (SH, 133b). The information collected therein is converted into a multiple processing signal by a multiplexer (MPU, 134), and the output signal of the multiplexer 134 is converted into a digital signal by an A / D converter 135, and then stored in a memory. The information stored and stored in 131 determines whether or not the short circuit is detected by the calculation circuit 132.

On the other hand, the calculation circuit 132 compares the current and voltage data immediately before the failure and the current and voltage data immediately after the failure to determine whether or not a short circuit.

Accordingly, the short circuit detection unit 130 may be caused by determining and detecting a short circuit through primary current information of the current converters CT_R, CT_S, and CT_T and primary voltage information of the voltage converters PT_RS and PT_ST. Regardless of whether there is an abnormality of the complex relay device, by enabling power interruption, there is an effect that the protection of the load side can be made more secure.

As described above, according to the present invention, the present invention integrates the protection function of the main protection relay applied to the existing switchboard and implements the digital method to perform the complex monitoring and protection function of the switchboard power. protect

The short circuit detection unit can improve the reliability of the function to determine whether the short circuit in advance to protect the load side by cutting off the power irrespective of whether the central processing unit is abnormal.

Claims (2)

Input side and trip / alarm connected to the secondary side of the current converters CT_R, CT_S, CT_T, and the secondary side of the voltage converters PT_RS, PT_ST and the secondary side of the open triangle-connected voltage converters PT1, PT2, PT3. An output side of which the contact is connected to the excitation coil of the AC disconnection / contactor for the contact output, an instrument transformer part for inputting the outputs of the current converter, the voltage converter and the image current transformer, and the current together with the instrument transformer part An input converter for converting the outputs of the converter, the voltage converter and the image transformer to an internal processable range, a low pass filter for removing a high frequency signal from the output of the input converter, and a center of the output of the low pass filter. A multiplexer for supplying one channel to a processing device, an analog / digital converter for digitizing an output of the multiplexer, and an output from the multiplexer A digital signal processing processor (DSP) for detecting a fault and processing the data into a data capable of performing a protection algorithm, a central processing unit for performing a protection algorithm with a signal from the digital signal processing processor, and connected to the central processing unit Back-up memory for backing up the correction value of each relay element and communication module connected with the central processing unit to transmit the fault information to the central monitoring unit in case of fault detection, and some relay elements depending on the protection target. Dip switch setting unit for selecting to perform only a function, a button switch input unit for allowing a user to correct various correction values for each relay element, and a display unit for displaying the various correction values and various electric amounts input to the current switchboard. In the composite relay device consisting of, Dual port for storing data in the short circuit detection unit connected to the primary side of the current converter (CT_R, CT_S, CT_T) and the primary side of the voltage converter (PT_RS, PT_ST), the digital signal processor and the dip switch setting unit Memory (Dp ram), The short circuit detection unit determines whether a short circuit in advance, and the power relay to protect the power receiver by cutting off the power irrespective of whether or not the central processing unit is abnormal. The method of claim 1, The short-circuit detection unit sample hold A (SH) for collecting primary side current information of the current converters CT_R, CT_S, CT_T, and sample hold B (SH) for collecting primary voltage information of the voltage converters PT_RS, PT_ST. A multiplexer (MP) for multiprocessing the collected information, an A / D converter for converting the output signal of the multiplexer into a digital signal, a memory for storing the converted signal, a current just before failure occurs, And a calculation circuit configured to perform a calculation to determine whether a short circuit is made through voltage data.