SU1584023A1 - Device for protection of automatic device of distribution substation - Google Patents

Abstract

The invention relates to the field of relay protection and automation of concentrated elements of power systems and can be used in a complex of substation protection and control systems. The aim of the invention is to improve the reliability of operation due to the self-control of the device, as well as to expand the functionality by ensuring the registration and transmission of the device-controlled parameters of the protected object to the upper level of control and receiving control actions from it. The goal is achieved by the fact that information about the state of the power facility, i.e. its currents, voltages, and the position of the switches are inserted into the device, formed into arrays, and recorded into random access memory. Then, in accordance with the algorithm, the device performs the required set of relay protection functions (up to switching off the switches), controls the presence of a ground fault and voltage, while ensuring an increased accuracy of the specified settings, if necessary, starts the automatic transfer of the reserve, transmits the controlled parameters of the protected object on the upper level of control, and also performs the diagnosis of the elements of the device and the communication channel with the indication of health and automatic restart of the device and possible SBO's operation of the program. 6 hp f-ly, 7 ill.

Description

The invention relates to power engineering, in particular to relay protection and automation of substation busbars with a voltage of 6-10 kV and their outgoing lines.

The purpose of the invention is to increase the reliability of operation due to the self-control of the device, as well as expanding the field of application by ensuring the registration and transmission of the device-controlled parameters of the protected object to the upper level of control and receiving control actions from it.

FIG. 1 shows a single-line distributional pattern

substations of 6-10 kV, equipped with a protection and automation device; in fig. 2 is a functional diagram of a protection and automation device; in fig. 3- functional block I / O; in fig. 4 - block diagram of the input discrete signals; in fig. 5 is a diagram of the control output unit; in fig. 6 is a functional diagram of the operation of the protection device; in fig. 7 is a flowchart of a current protection system function.

The protection and automation device of the distribution substation 1 contains current transformers 2 (CT) connected respectively to each of the outgoing lines with switches 3 to the circuit of sectional switch 4, as well as to the circuit of two switches of the substation inputs, voltage transformers 6 of the three phases of both sections of the substation bus 7, intermediate transformers 8, which are connected to the series-connected multiplexer 9, analog-to-digital converter (ADC) 10, input-output unit 1 1 and micro PLM 12, time sensor 13, of a set of counting decades, a discrete signal input unit 14, a statute input unit 15, a control output unit 16, a test control unit 17 each connected to the microcomputer 12 each through its own input-output unit 11, a programmable timer 18, a transceiver 19. At the same time, the outputs of the control actions block 16 are connected to the control actuators 20 by switches 3-5, the first, second and third outputs, the data bus of the programmable timer

18, transceiver data bus

19, as well as the data bus of the test control unit 17 are connected directly to the microcomputer 12, the input and output of the transceiver 19 are connected to the communication channel 21, with the first, second and third outputs of the clock unit 22 connected to the control inputs of the transceiver 19, sensor 13 time and programmable timer 18, and the fourth - to the microcomputer 12.

The setpoint input unit 15 contains a decoder 23, whose inputs are its inputs, and each output is connected to a group of

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diodes 24, the cathodes of which are combined, and the anodes are connected to the keys 25, and the outputs of all the keys 25 are combined into groups and are the outputs of the setting input unit 15.

The transceiver 19 contains a programmable serial interface 26, the data bus of which is the data bus of transceiver 19, the input (receivers) of the serial interface 26 via the first optical key 27 is connected to the output of the first amplifier 28s whose input is the input of the transceiver 19, and the output (transmitter a) serial interface 26 through a second optocoupler switch 27 connected to the input of the second amplifier 28, the output of which is the output of the transceiver 19.

The test control unit 17 contains a setting mode master 29, the first eight inputs-outputs of which are the first eight inputs-outputs of the test control unit 17, and the ninth output is connected to the first input of the unit

30 indications, the remaining eight inputs of which are the eight inputs of the test control unit 17, and the tenth output of the mode setter 29 is connected to the input of the additional unit

31, the data bus of which is the data bus of the test control unit 17.

I / O unit 11 contains a parallel I / O software interface 32, which, in turn, contains three bi-directional eight-bit registers, with the eight inputs of the first register being inputs of the I / O unit 11, sixteen input-outputs of the second and third registers. The inputs are the 5 mi-outputs of the I / O unit 11, the twenty-fifth and twenty-sixth inputs of the parallel interface 32 are connected to the address selector 33, the inputs of which are the inputs of the input-output unit 11, and the data bus of the interface 32 is th input-output data block 11.

Parallel Interface Registers

32 can independently program the microcomputer 12 to the input or output. The number of interface registers involved is 32 I / O blocks 11, depending on which block is connected to it.

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The protection and automation device contains six I / O units 11 thus completed. Four of them do not have a third register. Using the input / output unit 11, the discrete signal input unit 14, setpoint input unit 15, control output unit 16 and test control unit 17 are connected to the microcomputer 12. The device contains two more similar input / output units. In addition to the previous four, eight additional inputs of the third register are additionally involved in each of these 11 blocks of type 11, and in the block 11 of the I / O connected to the A / D converter 10, these eight inputs are connected to the multiplexer 9 , and in the I / O module C connected to the time sensor 13, they are connected to the time sensor 13 directly as output.

The discrete signal input unit 14 contains an array of sensor-contacts 34 sensors on the object, one of the outputs of which are combined and connected to optocoupler switches 35, whose inputs are the inputs of the discrete signal input unit 14, and the other outputs are connected to the anodes of the separation diodes 36 grouped and connected to optocouplers 35, the outputs of which are the outputs of the discrete signal input unit 14.

The block 16 of the issuance of control actions contains a set of capacitive filters 37, the inputs of which are its inputs, and the outputs are connected to the matrix of keys 20, controlling

intermediate transformers 8, where they are transformed into equivalent voltages.

The voltages obtained step on the inputs of the analog multiplexer 9, which, in accordance with the binary code, on its control inputs connects one of the analog signals to the input of the A / D converter 10, which performs equivalent conversion of the measured analog signal to a 12-digit digital code. The control of the ADC 13 and the analog multiplexer 9 is organized in accordance with the system program algorithm using the parallel interface 32 of the input-output unit 11, through which the required number code is specified

the analog signal to the control inputs of the analog multiplexer 9, and a control signal is issued to trigger the ADC 10. The digital 12-bit equivalent code of the analog signal obtained as a result of conversion to ADC 10 is inputted into the microcomputer using the same parallel interface 32 block 11 input-output.

0 The parallel interface 32 is connected to the microcomputer 12 via the address selector 33. The address selector 33 of each I / O unit 11 is set to its specific address,

, thanks to which the microcomputer 12, issuing the appropriate address to the system bus, can select the required input-output unit 11 and exchange information with the unit that

0 This I / O unit is connected.

All monitored block contacts of 34 switches 3-5 at the facility are combined into groups of eight sensors in a row and eight in a column. Op

by issuing a voltage to the solenoid off-D5 POC of the states of the auxiliary contacts 34,

switches (3-5), the filter containing the first capacitor 38 connected to the first register 39 and the separating anode

the diode 40, to the cathode of which the interface is connected to the 50 interface 32 of the input-output unit 11.

the second resistor 41, the second capacitor 42, and the input of the operational amplifier 43, whose output is the output of the filter 37, are missing.

The device works as follows.

Information about the state of the power facility - the current from the primary CT 2 and the voltage from the TN 6 - is supplied to

matrix (i.e., input and transformation of discrete signals monitored at the substation), is carried out using parallel

In order to control the matrix, two registers A and B are involved in the parallel interface 32, while register A in the process of programming the interface is configured for information output, and register B for input. The outputs of register A and the inputs of register B are connected to the block of the contacts 34 by means of optocouplers 35, which ensures the galvanic isolation of the system with the block contacts of 34 sensors on the object.

Thus, one of its outputs is connected to the outputs of register A, and the other via dividing diode 36 to the inputs of register B. Dividing diode 36 is necessary to eliminate the influence of each other on the block contacts united in one row of the matrix.

The interrogation of the state of the sensors 34 is performed sequentially in columns on the initiative of the microcomputer 12 in accordance with the system operation algorithm. So, for example, if it is necessary to enter the state of sensors 34 in the column with the number 0, Tq, microcomputer 12, enter in register A of the parallel interface 32 of the input-output unit 11 a code with a logical 1 signal in bit 0 and O signals in the remaining seven bits. If the individual block contacts 34 in column 0 are closed, signal 1 is fed to the corresponding register B input. Microcomputer 12, reading the state of register B inputs, unambiguously receives information about the state of block contacts 34, combined into column number 0 .

If it is necessary to enter into the system the position of the auxiliary contacts 34 of all switches of the microcomputer controlled at the substation, 3-5 should sequentially output a signal 1 in each register bit A and read each time in register B the status of the auxiliary contacts 34.

The possible bounce of the auxiliary contacts 34 when switching the switches is eliminated programmatically by rereading the state of the sensors. If in the process of n-fold reading of the microcomputer 12 a change in the sensor state is registered, the read cycle is repeated until the end of the chatter.

The signals monitored by the system (current, voltage, and the position of the switches of the protected object) are formed into arrays and recorded in the operative memory of the microcomputer 12. The records are updated as the arrays are transmitted to the control room and printed out.

Microcomputer 12 directly executes relay programs.

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protection and automation: maximum current protection (MTZ) of inputs and waste connections, earth fault monitoring and isolation conditions, as well as automatic backup power switching (AVR), while microcomputer 12 controls the operation of all other units of the system in according to the algorithm.

Constant memory and recalculation factors necessary for processing the initial data, templates for printing the information about the state of the protected object, as well as all subroutines that allow the device to operate the algorithm, are stored in the microSVM 12 permanent memory device.

The input of the current and time settings into the system is organized using code switches 25 located in the Zlok 15 settings box. Microcomputer 12 through the parallel interface 32 of the I / O unit 11 and the decoder 23 sets the number of the setpoint to be changed, and then reads the address from the type field. its specific value stored in the persistent storage device of the microcomputer 12. The register A of the interface 32 of the BVV 11 and the number of outputs of the decoder 23 are determined by the required number of changeable settings.

The time sensor 13 consists of a set of decadal voltage dividers and performs real-time counting, time indication on the digital display and time entry into the system on request of microcomputer 12 (date, hours, minutes, seconds, tenths of a second). When a malfunction is detected, the microcomputer 12 reads from the time sensor 13 the exact time of the occurrence of the damage.

The block of 22 clock pulses, continuously issuing pulses with a given frequency, ensures synchronous operation of the blocks connected to it (microcomputer 12, time sensor 13, programmed timer 18 and transceiver 19).

The countdown of the required setting of the protection response time is organized using a programmable timer 18, consisting of three independent counters (0, 1 and 2).

The first two internal subtractive counters form time intervals.

In the case of MTZ time delays, output 0 and AVR are output 1. Signals from these outputs as interrupt vectors are fed to the interrupt block of microcomputer 12 (not shown). Timer channel operation is programmed using simple I / O operations. Each of the three channels is programmed separately by writing the control word mode and the programmed number of bytes to the register.

The 2nd counter of the programmable timer 18 is used to organize automatic restart of the device in case of possible failures in the functioning algorithm. At the beginning of each program cycle, Timer 18 records a number in accordance with which Timer 18 counts a specific time interval. If during this time the program did not have time to complete the full working cycle and overload the 2nd counter, then at the output of the 2nd counter of timer 18 a Reset signal appears, which automatically restarts the device. The time interval is obviously chosen somewhat longer than the duration of the full working cycle. Therefore, the device will be restarted only when the program is crashing and looping.

The connection of the programmable timer 18 and the transceiver 19 to the system bus of the microcomputer 12 is organized using an address selector (not shown), the assignment of which is similar to the assignment of the selector 33 to the address of the I / O unit 11.

The transmission of information is organized using the serial interface 26 of the transceiver 19, where the parallel code of the transmitted information is converted into serial parity (odd evenness) in blocks of transmitted information, exchanged with the common bus of the device. Using optocouplers 27 and amplifiers 28, which are also part of transceiver 19, the device is galvanically isolated from the communication channel 21 (for example, telephone) and amplified signals. In the case of use as a channel 21 of the electrical network with a voltage of 6-10 kV, i.e. when transmitting information through the power network,

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The transceiver 19 is additionally fitted with a high-voltage capacitive coupling filter.

Similar to the auxiliary contacts 34 of the switches 3-5, the optocouplers 20, | controlling the output of the voltage to the solenoid off (on) the switches 3-5, are grouped into columns (eight pieces each) and lines (eight pieces each). A group of eight keys with one sequence number of the input of register B constitutes a column of the same name. The control of all the keys 20 is carried out with the help of the parallel interface 32 of the input-output unit 11. Register A issues signals for controlling the keys 20 and for issuing the supply voltage to the corresponding rows of the matrix. Register B provides signals for connecting the common wire from the matrix power supply unit to its columns. Thus, to operate from the keys of the matrix 20, it is necessary to simultaneously issue the inclusion signals of the corresponding row and the corresponding column. I

To eliminate the possibility of false control by a switch with single spurious signals and interference, the inputs / outputs of registers A and B of interface 32 of unit 11 are connected to control inputs of keys 20 through special filters 37 (in Fig. 5, the filter is highlighted by a dotted line). The filter 37 is built on the principle of capacitive storage. To issue a control signal to one of the keys 20 of the microcomputer array 12 in the corresponding register register A and. B records successively in time zeros and ones with a given frequency for a certain time interval. This sequence through the differential chain 38 and 39 and the separation diode 40 charges the capacitive storage 41, 42. The constant discharge time is chosen so that the capacitive storage is charged before the key has a voltage of 15-20 pulses from the corresponding discharge. register. The operational amplifier 43, having a large input impedance, eliminates the influence of the low-impedance control input of the matrix key 20 on the formation and amplification of the capacitive storage signal.

The self-control of the device is carried out using the test control block 17. The microcomputer 12, at the times indicated in the program, is counted by the time sensor 13, through block 11, calls the mode setter 29, which determines the test mode required at a given time, selects the corresponding equipment condition monitoring subroutine in the additional memory block 31 and signals selected test mode in display unit 30. The result of the test subroutine is output to the display unit 30 via the transceiver unit 19 and the communication channel 21 to the upper control level. A code selector can be used as a mode setting 29; a set of LEDs can be used as an indication unit 30.

When developing a specific device implementation scheme, the I / O unit 11 uses a BIS KR580VV55 microcomputer 12 as a parallel interface 32 — the MK-01 microcontroller, based on the KR580BM80A processor; as a programmable timer 18, BIS KR580BB53, a transceiver 19 and KR 580BB1.

However, the proposed device protection and automation can be performed on another elemental base.

The device is started and initialized automatically at the moment of turning on the power, either manually when pressing the System Initialization button, or automatically when the system restart timer of the device is triggered.

After initialization, before the next cycle of the main program of the device operation, the test control routine of the entire equipment is stored at the indicated times, stored in the additional memory block 31, and if the test control routine detects a malfunction, the system health indication 30 signals this , a corresponding message is sent to the communication channel, and if it is impossible to continue the execution of the program, the system goes into a standby state. If the test is successful, it also fixes the system health indication block 30 and the program continues.

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The next step is to load the restart timer 18 and enter the current information about the state of the power facility: the values of the currents flowing through the switches of the inputs 5 and the outgoing connections of 3 bus sections; the values of the three phases of the voltages in sections 7; section switch current 4: informative parameters characterizing the state of isolation cable lines of bushings and outgoing connections of bus sections; current time; switch position. Then, a program of system current protection (FCZ) and ground fault monitoring, as well as control of voltages on busbar sections and when the relevant conditions are met, namely, the absence of short circuit voltage, is performed. and lowering the voltage, the AVR is started. If there is a ground fault, the device acts on the signal. If the result of the execution of the program indicates the presence of damage in the protected area, the microcomputer 12 generates a signal to turn off the switch of the protected element.

The next stage of operation of the device is the transition to a subroutine monitoring the state of isolation of cable lines of connections. If the isolation deteriorates at any of the connections, a command is formed to issue the relevant information about the isolation status of this cable line to the control room. The final stage of the execution of the system program is the dispatching routine and the transfer of the necessary information to the control room.

As can be seen from the algorithm, the system uses a multilevel vector interrupt system (VP):

on VPO from timer 18, a signal is received that the time delay set for the overcurrent device is expired;

on VP1 from timer 18, a signal is received that the time delay set for the ATS is expired;

on VP2 in microcomputer 12 from time sensor 13 every 2, 4, 8 or 16 minutes (optional) signals are sent to the dispatcher that there is a ground fault at the substation and that the operating personnel restores the normal operation of the substation after the causes of the accident have been eliminated ;

(according to the SCR, the microcomputer 12 is given a signal about the presence of a request from the control room to issue an information message about the state of the object;

on VP4 in microcomputer 12, a signal is received that the transceiver is ready | To receive and issue the next byte (information to the dispatch hub;

the CWP from timer 18 signals the expiration of the time delay set for the generalized current protection (RTD) of the first section of busbars;

On VP6 from timer 18, a signal is received that the time delay set for the OTZ of the second bus section has expired.

The algorithm of functioning of the system current protection (FCZ) with current-dependent time lag is structurally composed of two similar parts (by the number of bus sections).

One part of the FCZ algorithm (Fig. 7) consists of several fragments: MTZ inputs, control of current deviation (CAT), and generalized current protection (RTD) of the outgoing connections.

The first step of the FCZ routine is to perform the overcurrent function of the inputs of the first busbar section and the sectional switch, namely, the analysis of the current value of input currents and, in case of overcurrent or setpoint, shutdown of the input switch.

Next, the KO G-1 fragment is executed, which includes an analysis of the absolute values of the currents at a given time moment j IJBB I and at the previous time point 1t1.a1 as well as a comparison of the calculated current deviation (modulo) juljl Ujee - Ij-m I with the setting 1Mus Under the conditions

Ujeel lij.iMl Ibljl iJjcT

a transition to the HTA-1 fragment occurs (i.e., the launch of the HTA-1), which includes a cycle of viewing the outgoing currents

connections I

Yar

and comparing each one with its own setting. In the case of lycs.i, the program fixes those attachments i in which

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ryh discovered k.z. and, depending on the magnitude of the short-circuit current, selects from the tables an appropriate time delay for the protection to operate, after which it switches off the switch of the damaged connection.

Then, the second part of the FCZ algorithm (not shown in Fig. 7) is executed, similar to the first, namely, MTZ-P, CAT-P, HTA-P.

The proposed device can be used when performing burdock protection and automation of power supply substations with a voltage of 6-10 kV.

The effectiveness of the invention is determined by the increased reliability of operation due to the self-control of the device, which allows to increase the uninterrupted power supply time and reduce the time spent by the operating personnel on prevention, periodic inspections and repairs of protection elements. Registering and transferring the parameters monitored by the device to the upper level of control, fixing the development of an emergency situation in time, increases the efficiency of managing the protection system and the protected object, i.e. they accelerate the analysis of what is happening and the adoption of more sound management decisions, as well as provide a quick diagnosis of the elements of the protected object and protection in order to shorten the time for troubleshooting and repair.

Adaptation of the device to any changes in the modes and configuration of the protected object is performed at the software level.

Claims (7)

1. A protection and automation device for a distribution substation containing intermediate transformers according to the number of protected connections, a series-connected multiplexer, an analog-to-digital converter, an input-output unit and a micro-computer, as well as a block of clock pulses, characterized in that reliability of operation due to self-control of the device, as well as to expand the scope of application by providing a radio register and transmitting the parameters controlled by the device  51 object to the upper level of control and receiving control actions from it, a time sensor consisting of a set of counting decades, a discrete signal input unit, a setting input block, a control action issuing unit, a test control unit connected to a microcomputer each by means of its own I / O unit, as well as a programmable timer and transceiver, while the outputs of the control output unit are connected to the executive controls of the switches, the first, second, third outputs the data bus of the programmable timer and the data bus of the transceiver, as well as the data bus of the test control unit are connected directly to kmikroZVM, the input and output of the transceiver are connected to the communication channel, the first, second and third outputs of the clock impulse unit are connected respectively to the control inputs of the transceiver sensor time and programmable timer, and the fourth - to the microcomputer. 2. The device according to claim 1, characterized in that the input-output unit contains a parallel input-output interface, the first eight inputs of which are the inputs of the input-output unit, and the following sixteen inputs-outputs of which are input-output The I / O unit, the twenty-fifth and twenty-sixth inputs of the parallel interface are connected to the address selector, whose inputs are the inputs to the I / O unit, and the interface data bus is the data bus of the I / O unit. 3. The device according to claim 1, characterized in that the input unit of discrete signals contains a matrix . sensor contacts on the object, one of the outputs of which are combined and connected to optocouplers whose inputs are inputs to the input unit of discrete signals, and other outputs connected to the anodes of the separation diodes, the cathodes of which are combined into groups and connected to the optocouplers whose outputs are outputs of a discrete signal input unit. 4. The device according to claim 1, of which is - that the input block 0 five 0 4023  five 30 35 40 45 50 55 sixteen The setpoint contains a decoder, the inputs of which are the inputs of the setpoint input unit, and each output of which is connected to a group of isolation diodes, the cathodes of which are combined, and the anodes are connected to the keys, and the outputs of all the keys are combined into groups and are the outputs of the setting input unit. 5. The device according to claim 1, wherein the transceiver comprises a programmable serial interface whose data bus is a transceiver data bus, the serial interface input is connected to the output of the first amplifier, the input of which is the transceiver input, and serial output via a second optocoupler key connected to the input of the second amplifier, the output of which is the output of the transceiver. 6. The device according to claim 1, characterized in that the control output unit contains a set of capacitive filters, the inputs of which are inputs to the control action output unit, and the outputs are connected to a matrix of keys that control the output of the voltage to the solenoid switch-on and switch-on switches, the filter contains the first capacitor connected to the first resistor and the anode of the coupling diode, to the cathode of which the second resistor is connected, the second capacitor and the input of the operational amplifier, the output of which is course filter, the second terminals of the first and second resistors, a second capacitor connected to a common ground bus. 7. An arrangement according to claim 1, characterized in that the test control unit contains a mode setter, the first eight inputs / outputs of which are the first eight inputs / outputs of the test control unit, and the ninth output of which is connected to the first input of the display unit, The inputs of this are the second eight inputs of the test control block, and the tenth output of the mode setter is under 17,158,42318 keys to the input of an additional unit with the data bus of the test terminal, whose data bus is Ethernet. ./ 2 P SchU / V t c-yon P jurir 1 i f i "and g F Shg / g / zo 2 / KOV8SI Start watts work 5 Sv / t (manual) Start with 8kl power fntt Editor 0. Head Compiled by Yu.Postnikov Tehred M. Khodanych Order 2260 Circulation 488 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5 Production and Publishing Combine Patent, Uzhgorod, st. 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