EA021619B1 - Apparatus for transmission of commands for relay protection and emergency automation over high-frequency channels - Google Patents

Abstract

The invention relates to electrical engineering and is directed for use in relay protection systems and automation over high-frequency channels. The technical result is aimed at improving interference protection (elimination of noise influence in power transmission lines to reception of emergency commands), reliability (elimination of errors of emergency commands), and safety (elimination possibility reception of false emergency commands). An apparatus comprises power sources, external interfaces, a transmitter unit consisting of the central processor, input of which is connected to N-number moduluses of input action, to a signal modulus, to a telemechanical modulus and to the external interfaces and an output of which is connected to a modulus of power amplification and to a modulus of output linear filter, and a receiver unit consisting of the central processor, input of which is connected to a modulus of input linear filter, and the output is connected to N-number of relay moduluses, to the signal modulus, to the telemechanical modulus and to the external interfaces. A modulus of signal forming is further added to the transmitter unit, one inputs of which is connected via a parallel busbar to the input of central microprocessor and to the output of the telemechanical modulus, and output to the modulus of power amplifier, which, in its turn, is connected to the output linear filter, wherein a demodulator modulus is further added to the receiver unit the input of which is connected to the input linear filter and one of outputs, via parallel busbar, to the input of the central microprocessor, and for connection of the central microprocessor to N-number of relay moduluses further N-number relay control moduluses are added, wherein the modulus of control signal serves for forming the control signal and signal-commands using the method of the direct spreading spectrum by code M-sequence (DSSS) by binar phase manipulation, wherein the demodulator modulus, which receives the signal from the linear filter modulus, provides computation of correlation of the received signal with code M-sequence of the control signal or the signal-command by the method of "optimum receiption".

Description

The invention relates to electrical engineering and is intended for use in relay protection systems and automation through high-frequency channels.

State of the art

One of the most reliable systems providing effective control by the electric power complex is relay protection and emergency automation. The principle of its work is automatic control over electric power systems (EPS), which is carried out by special devices. These devices, if necessary, also take control of damaged EES units.

Modern relay protection and automation is based on the latest microprocessors. Such protection ensures the safety of any power plants - from small power plants to the largest industrial enterprises. It also performs signaling functions, registers events occurring at EPS. Also, automation instantly detects and turns off faulty units, without disrupting the entire system, is responsible for restoring normal operation modes (for example, turning on equipment after an emergency shutdown or connecting equipment to backup power).

Known high-frequency equipment of the automation channels HF AKA Cedar (Certificate of the Russian Federation No. ROSS YI.ME27.N01798 from 04/03/2009, see. Yr: //tetete.iep8egu.gi/ya1a/8ep%20keyg.ry1), intended for the formation of high-frequency relay channels protection and emergency automation.

The basic set of AKA Cedar equipment includes two units: a high-frequency transmitter (8/16/32 signal-command shaper) and a high-frequency receiver (8/16/32 signal-command identifier).

The basic set of AKA Cedar provides the transmission of emergency control (PA) commands with a single-frequency or two-frequency serial code;

receiving PA commands in the absence of a control frequency signal and the presence of a sufficient level of the command signal at the output of the amplifier-limiter;

continuous automatic monitoring of the health of the high-frequency path by transmitting a control frequency signal with a reduced power level;

periodic (with an interval of 2 ms) monitoring of operability of the functional units of the equipment: from the input circuits of the transmitter to the output relays of the receiver;

recording in non-volatile memory of transmitted and received commands (date, time, command number); the operator’s work with the keyboard and display of the PRC unit (central processor) for selecting / setting operating modes and equipment parameters through a multi-level menu;

signaling the passage of commands, as well as malfunctions of the RF channel and equipment (with the definition of a faulty unit). Information about the last event is shown on the display until confirmation or new information.

The main disadvantage of this equipment is the lack of protection from industrial interference (signals from transmitters of energy communication channels, radio frequency devices, etc.).

A digital device for transmitting commands of relay protection (RE) and emergency automation (PA) via a high-frequency channel UPK-C is intended for use in emergency control systems and relay protection of power systems using 110-10-1150 voltage transmission lines as a communication channel. kV (Certificate of the Russian Federation No. ROSS KI.ME27.N01790 No. 892817 dated 03/23/2009, see: Yr: //tetete.rgo8OY8u81et8.gi/1agde1tade.b1t? 1t§ = 1158, the website of the company Rg8oy Lyr: // tete. rgo8Oi8u81et8.gi / rgois18 / rgoisi1b1t? p1i = 54). This set of equipment consists of a UPK-Ts receiver and a UPK-Ts transmitter, in which the transceiver path and control logic are carried out mainly using the program. The main differences of this device are that the commands are generated in a group signal in the 4 kHz band by a parallel two-frequency code, which significantly increases the noise immunity of the transmission path and the reliability of the transmitted information;

there is the possibility of transmitting telemechanics signals with a speed of 200 Baud, regardless of the transmission of commands;

continuous monitoring of all nodes and blocks from the input command circuits in the transmitter to the contacts of the output relay commands in the receiver;

it is possible to configure the algorithm for processing commands programmatically; on a 4-line LCD display from the non-volatile event log displays information about the start and end time of the transmitted commands and about emergency situations;

There is a synchronization of the receiver clock with the transmitter clock with an accuracy of 2 ms.

The main disadvantage of this equipment is the lack of protection from industrial interference (signals from transmitters of communication channels, radio frequency devices, etc.).

Closest to the invention, which is claimed, is the equipment of high-frequency communication channels, telemechanics, data transmission and relay protection commands and emergency automation

- 1 021619 for high-voltage power lines (Patent for utility model of the Russian Federation No. 98656, IPC Н04В 3/00, publ. 10/20/2010), including a signal processing unit, a unit for receiving / transmitting relay protection and emergency control commands, a control unit and station control, power amplifier, linear matching device, power supplies and a terminal in which the power amplifier is made in a two-stage scheme with a double power reserve of each stage, with the possibility of providing signal amplification in case of failure of one stage (hot standby). It is also equipped with a backup power supply with the ability to provide power in case of failure of the standard power supply (hot standby), and the power supply contains switching elements for the input voltage from 48 to 220 V DC and 220 V AC. It is also equipped with a backup communication channel via a dedicated telephone line and a backup communication channel via C8M channels, and the relay / emergency command receiving / transmitting unit is installed separately from the main station at a distance of up to 1200 m and an optical fiber cable connected to it.

The disadvantage of this equipment is the need for a wide band of communication frequencies, the high cost and complexity of implementation, low noise immunity of the transmission of blocking signals.

SUMMARY OF THE INVENTION

The basis of the invention is the task to create such equipment for transmitting relay protection and emergency control commands via high-frequency channels, in which, by introducing a signal conditioning module into the transmitter unit and a signal demodulator module into the receiver unit, which use the principle of spectrum expansion with a binary phase code M-sequence direct sequence manipulation (Ό888) for transmitting a control signal and command signals, an increase in noise immunity is achieved (exclusion of noise detection in power lines for receiving emergency commands), reliability (eliminating the omission of an emergency command) and safety (eliminating the likelihood of receiving a false emergency command).

The specified technical result is achieved by the fact that in the equipment for transmitting relay protection and emergency control commands via high-frequency channels, containing power supplies, external interfaces, a transmitter unit consisting of a central processor, the input of which is connected to the Ν-number of input action modules, with an alarm module, with a telemechanics module and with external interfaces, and an output that is connected to a power amplifier module and with an output linear filter module, and a receiver unit, consisting of a central o the processor, the input of which is connected to the input line filter module, and the output, which is connected with the Ν-number of relay modules, with the alarm module, with the telemechanics module and with external interfaces, in which according to the invention an additional signal conditioning module is added to the transmitter unit, one from the inputs of which is connected via a parallel bus to the input of the central microprocessor and the output of the telemechanics module, and the output to the power amplifier module, which, in turn, is connected to the module of the output linear filter tra, and a signal demodulator module is additionally introduced into the receiver unit, the input of which is connected to the linear input filter module, and one of the outputs is connected via a parallel bus to the input of the central microprocessor, and an additional Ν-quantity is added to connect the central microprocessor to the количеством-number of relay modules relay control modules, and the signal shaper module is designed to generate a control signal and command signals by the method of direct spectrum expansion with a code M-sequence (Ό888) binary phase manipulation, and the demodulator module, which receives the signal from the linear filter module, provides the calculation of the correlation of the received signal with the code sequence of the control signal or command signal using the optimal reception method.

For the proposed equipment for transmitting commands of relay protection and emergency control via high-frequency channels, a name is proposed - Kalina.

The advantage of the proposed technical solution is the increased noise immunity of the command reception equipment: providing better, in comparison with analogs, probabilistic characteristics of command reception under the influence of interference of industrial origin with the same noise immunity as white analogs. Interferences of industrial origin (interference from radio emitting means, combination signals of other transmitters, etc.) are present at the input of the receiver together with thermal noise, which has the character of a white Gaussian noise, but, in contrast, have finite values of the frequency bandwidth.

The influence of such interference is greater, the closer their parameters with the parameters of the useful signal. For example, a harmonic signal will be the most effective interference for a signal of the form of an unmodulated carrier, if their frequencies coincide.

The reliability of the coincidence of the noise and signal parameters decreases with the complexity of the signal structure. Quantitatively, the degree of complexity is characterized by a signal base of approximately 2-ΔΡ-Τ, where ΔΡ is the bandwidth and T is the signal duration. The band ΔΡ in this case can be significantly wider than the minimum necessary for the transmission of information; band extension is provided by the use of an extension signal - a code sequence of manipulation, which is independent of the transmitted information. Such a signal is received by comparing it with a synchronized copy (with the same code sequence).

This method of increasing noise immunity is called the direct expansion of the spectrum of the code sequence (Όδδδ - Eyes! Bssssspss 8prteay 8res1itit).

The degree to which the receiver is unacceptable to interference is directly proportional to the spreading factor. Thus, the maximum possible noise immunity is determined by the bandwidth acceptable for signal transmission.

The proposed technical solution provides for the use of the entire (allotted to the standards) frequency band for transmitting a command signal providing increased immunity to interference from industrial facilities, while maintaining immunity to white Gaussian noise, due to the additional input of the signal conditioning module into the transmitter unit and into the receiver unit a demodulator module of a spectrum spreading signal (spreading code).

The signal conditioning unit includes two main nodes: a modulator and an amplifier. The automation initiates the generation of a harmonic signal δίη (Δωί), the duration of which is T _k , and the frequency ω is equal to the center frequency of the selected frequency channel with a bandwidth Δί. The modulator performs phase π-manipulation of the signal with code φ ₃ (1). corresponding to the transmitted command (or control signal in the absence of commands). The amplified signal is sent to the line.

In the receiver, the bandwidth of the channel Δί is selected (from the word selectivity) by a band-pass filter, then the selected signal is fed through the amplifier to the multiplier. From the result of multiplying the low-pass filter is allocated a constant component _{Οθ8 (ω ί + φ ^ ί} )) = CD8 (0), which, after the accumulation of the integrator is compared with a threshold for deciding the team reception.

The multiplier and the elements following it make up the correlator structure, which in the theory of signal reception is called the optimal receiver.

The essence of optimal reception is to use a copy in the receiver that matches the received signal in all coordinates. Obviously, to achieve the maximum output signal, the correlator (equal to zero CoDo, + φ ^ ί)) = Co8 (0)) requires an exact temporal combination of copy and signal, which is realized by synchronizing the receiver to the transmitter.

The synchronization of the receiver is ensured by the control signal, which is continuously transmitted in the form of an extension code corresponding to it. In the general case, the equipment uses the N + 1 extension code, where N is the required number of commands. As extension codes, pseudo-random sequences from the family of M-sequences having minimal cross-correlation are used.

Brief Description of the Drawings

The essence of the invention is explained by the drawings, where in FIG. 1 shows a block diagram of a transmitter unit; FIG. 2 is a block diagram of a receiver unit.

DETAILED DESCRIPTION OF THE INVENTION

The equipment for transmitting relay protection and emergency control commands (see Figs. 1 and 2) consists of power supplies 1, a transmitter unit 2, which consists of a central processor 3, the input of which is connected to the Ν-number of input actions modules 4, which convert alarm signals coming from relay protection and emergency automation devices, with an alarm module 5, with a telemechanics module 6 and with external interfaces 7. The output of the central processor 3 is connected to the power amplifier module 8 and to the linear output module filter 9. The apparatus also contains a receiver unit 10, which consists of a central processor 11, the input of which is connected to the input line filter module 12, and the output, which is connected to the Ν-number of relay modules 13, to the signaling module 14, to the telemechanics module 15 and with external interfaces 16. Also, a signal shaper module 17 is additionally introduced into the transmitter unit 2, one of the inputs of which is connected via a parallel bus to the input of the central microprocessor 3 and the output of the telemechanics module 6, and the output to the power amplifier module 8, which, in turn, is connected to the output linear filter module 9, and a signal demodulator module 18 is additionally introduced into the receiver unit 10, the input of which is connected to the linear input filter module 12, and one of the outputs through a parallel bus with the input of the central microprocessor 11, and for connecting the central microprocessor 11 of the Ν-number of relay modules 13, an additional Ν-number of relay control modules 19 is introduced.

This equipment operates as follows. The input action modules 4 turn the alarm voltage into a parallel binary code and transmit it to the central processor 3. The signal shaper module 17 generates a phase-shift signal corresponding to the transmitted command or, in the absence of commands, to the control signal, using the spread spectrum method with a code sequence for transmitting emergency commands, performing π-manipulation of the harmonic signal δίη (Δωί) with code φί (1), which enters (in the form of a sinusoidal voltage) directly into the module of Tell signal 17 to a separate input (not shown) electrically isolated. The control signal is designed to maintain constant synchronization between the transmitter unit 2 and the receiver unit 10. In addition, the signal transmitted to the line contains information about

- 3 021619 current phase and, if necessary, telemetry data. Telemetry data is received from the telemechanics module 6 to the signal shaper module 17 through the central processor 3. The frequency of the linear signal can be set in the range from 24 to 1000 kHz with a step of Αί.

The output signal δ from the signal conditioning module 17 is fed to the power amplifier module 8, which is powered by a power source 1a. The power amplifier 8 is linear, the output power is adjustable in the range from 32 to 47 dBm in 1 dBm increments. Power control, as well as diagnostics, is carried out by the central processor 3. The level of out-of-band emissions at any frequency of the range 24-1000 kHz outside the operating band does not exceed minus 40 dB relative to the current value of the output power. Output impedance 75 ohms (nominal value).

The output signal δ from the power amplifier module 8 enters the line through the output line filter module 9.

The transmitter unit 2 also has external interfaces 7. This allows you to solve a variety of tasks, such as manual or automated diagnostics of equipment performance, checking electrical characteristics, setting configurations during commissioning, testing and modification of internal work programs. It also provides the ability to incorporate the device into the local network.

Next, the signal δ _ΒΧ through the input line filter 12 enters the signal demodulation module 18. The center frequency of the input signal can be set in the range from 24 to 1000 kHz with a step Δί. The frequency setting is performed by the Central processor 11.

The signal demodulator module 18 performs the following tasks:

receiving a pilot signal and supporting synchronization between the transmitter unit 2 and the receiver unit 10;

receiving emergency teams; receiving data about the current phase; receiving telemetry data; the formation of the output signal phase.

In the signal demodulator module 18 of the receiver unit 10, it is synchronized by continuously transmitting a control signal and determining the correlation of the received signal and copies of emergency command codes, then the demodulated received emergency command codes and telemetry data are transmitted to the central processor 11 using a parallel bus similar to that which is used in the transmitter unit 2.

Corresponding to the code of the received command, the central processor 11 conducts the inclusion of one or more outputs of the relay modules 13. To control these modules 13 with the central microprocessor 11, the relay control modules 19 are designed.

Telemetry data is output to the receiver unit 10 through the telemechanics module 15.

The phase signal is generated at a separate output (not shown) with galvanic isolation of the demodulator module 18 in the form of an analog sinusoidal signal with a frequency of 50 Hz.

The receiver unit 10, as well as the transmitter unit 2, supports communication with external devices using external interfaces 16.

Industrial applicability

Using this technical solution allows you to transmit the relay protection command of power facilities: acceleration, tele-shutdown, prohibition / permission to re-enable. Also, the transmission of emergency control commands: fixing the shutdown of overhead lines (overhead line), automatic voltage boost, asynchronous operation, a special load limiter, etc., and the transmission of the voltage phase of industrial frequency (for emergency control by angle).

Claims (1)

CLAIM Equipment for transmitting relay protection and emergency control commands over high-frequency channels, containing power supplies, external interfaces, a transmitter unit consisting of a central processor, the input of which is connected to the Ν-number of input action modules, with an alarm module, with a telemechanics module and with external interfaces, and the output of which is connected to the power amplifier module and to the output line filter module, and the receiver unit, consisting of a central processor, the input of which is connected to the input module a linear filter, the output of which is connected with the Ν-number of relay modules, with an alarm module, with a telemechanics module and with external interfaces, characterized in that the signal conditioning module is additionally introduced into the transmitter unit, one of the inputs of which is connected via a parallel bus to the central input microprocessor and the output of the telemechanics module, and the output is with the power amplifier module, which, in turn, is connected to the output line filter module, and a demodulator module with ignals, the input of which is connected to the linear input filter module, and one of the outputs is through a parallel bus with the input of the central microprocessor, and for connecting the central microprocessor with the Ν-number of relay modules, Ν-4 021619 the number of relay control modules is additionally introduced, moreover, the signal conditioning module It is intended for the formation of a control signal and command signals by the method of direct spectrum spreading by a code M sequence (Ό888) by binary phase shift keying, and the demodulator module, on which upaet signal from the linear filter module provides correlation calculation of the received signal with a pilot code sequence or M-command signal by the optimal reception.