JPS6378697A - Remote supervisory and controlling equipment - Google Patents

Abstract

PURPOSE:To aways acquire the hourly synchronization between a master timepiece in a master station and slave timepieces in slave stations without affecting the action of remote supervisory and control by switching a circuit to a backup transmission line for a remote supervisory and controlling equipment and inserting a time code generator for hourly synchronization and a time code decoder. CONSTITUTION:In the master station 0 an arithmetic processing circuit CPU0 isolates switching circuits CT01, CT02,... from code transmission circuits S01, S02,... through an output circuit DO02 at a time when the circuit CPU0 completes the transmission of changeover control commands for receiving a time code(at most an estimation of 0.5 sec is sufficient in consideration of different signal transmission speeds). The isolated circuits CT01,... are connected to the time code generator TG. After the switching, time codes that the time code generator TG outputs are modulated by modulator circuits M01, M02,... and they are transmitted to the slave stations 1, 2... through down lines L12d, L22d,... in the backup transmission line. Since in the slave station 1 the switching circuit CT1 is connected to the side of the time code decoder TD1, the output of a demodulator circuit D12 is handed to the time code decoder TD1, thereby receiving the time code.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a remote monitoring and control device having a function of synchronizing a master clock provided in a master station and a slave clock provided in a slave station. .

[Conventional technology]

As power system operations become more sophisticated, there is a need to accurately record and analyze the operating times and operating sequences of protection devices and equipment at each electrical station over a wide area, and when collecting measurement data, it becomes necessary to It became necessary to match the time points of data collection.

As a method to meet these demands, a clock 7 is installed in the master station and each slave station of the data transmission device, and the operation of the maintenance equipment and equipment is transmitted together with the time data of these clocks, and all operations are performed at a predetermined time. Slave station - There is a method of making 7 measurements at the same time, storing the measurement data in the memory, and then transmitting it to the master station. In this case, what is important is that the clocks of the master station and slave stations have an error that does not cause any practical problems. synchronization within the range of .

One method for achieving this synchronization is to provide a time code generator in the master station and a time code decoder in the slave stations, and to always connect them through a dedicated transmission path. If you do this, the timecode generator will generate a timecode that corresponds to the time of the master clock! It continues to be sent to the time code decoder of the slave station, and the time code decoder constantly receives this, and when the scheduled time arrives, it sends a pulse for time correction! In response to this, the child clock can adjust its time and synchronize with the time of the master clock. if,
If it is necessary to correct the error due to the transmission delay time, the above-mentioned time is corrected after this is corrected using data measured in advance.

An example of such a time code generator and time code decoder is HATHAWAY (USA).
) Type 251 and Type 2 released by
However, it is not necessary to always connect the time code generator and the time code decoder as described above, and synchronization can be achieved by connecting them intermittently. In other words, to prevent malfunction, the time code decoder normally locks the output circuit for about 5 seconds after receiving a signal, but if the time code decoder continues to receive the signal for longer than that, the time correction pulse will be output at the hour (or minute). Since it is designed to perform Z output, for example, the transmission line from the remote monitoring and control device's master station to the slave station (hereinafter referred to as 1 downlink 1) can be disconnected for 10 to 15 seconds before and after the hour, and this time is t. By connecting to a code generator and a time code decoder, it is possible to make time corrections. The transmitter/receiver circuit for supervisory control is time synchronized.
During this time, even if you try to control the slave station's equipment, you will not be able to send control codes, and the data from the slave station will be polled.
In the case of the method g) in which information is transmitted to the master station, there is a problem in that even if an accident occurs or a device operates at a slave station, the information transmission will stop during that time.

This invention was made to solve the above-mentioned problems, and provides a remote monitoring and control device that can perform time synchronization without affecting code transmission for remote monitoring and control during normal operation. The purpose is to

[Means for solving problems]

The remote monitoring and control device according to this invention has a master station and a slave station!
The main transmission line and the backup transmission line are connected 2X, and a switching control command from the master station to the slave station causes the first switching circuit and the second switching circuit! By switching, the time code generator of the master station and the time code decoder of the slave station are connected via the backup transmission path, and the master clock of the master station and the slave clock of the slave station are synchronized. 0 [Function] The time code generator and time code decoder for time synchronization in the present invention are switched and inserted into the backup transmission line of the remote monitoring control device, so that remote monitoring can be performed at all times. It is possible to synchronize the time between the master clock of the master station and the slave clock of the slave station without affecting the control operation at all.
Even if the main transmission line fails and the backup transmission line is used to transmit codes for remote monitoring and control, time synchronization can be achieved by interrupting the code transmission for a certain period of time! Make it possible to do the same.

〔Example〕

Hereinafter, a first embodiment of the present invention, shown in FIG. 1, will be described. 1st
In the figure, 0 is the master station of the remote monitoring and control device, and 1 is the slave station. Note that although there may be multiple slave stations 1 (slave stations 1, 2, etc.), they all have the same configuration, so only the circuit that faces slave station 1 in master station 0 is illustrated, and the following is omitted. ing.

In the master station O, GP is a display panel that displays the status of each slave station, CD is a control console for issuing control commands to each slave station 1, and T
W is a typewriter and CPU that records operations and data.
o is an arithmetic processing circuit, DOol.

DOo is an output circuit, DIa is an input circuit, TC is a typewriter control circuit, MC is a master clock, TG is a time code generator, CTol, CTo, . Switching circuit that temporarily disconnects and connects to the time code generator, Mo, 1
．． MOl, , M(, H, MO1! *”' is the modulation circuit, Doll * Doll * Doll t DO
1t*...' is a demodulation circuit, CLol.

CLo, ,... is a switching circuit that switches the uplink from the main transmission line to the backup transmission line, S01 t 5
(11 is a code transmitting circuit, Rol, Ro! is a code receiving circuit 0 Also, in slave station 1, CPU is an arithmetic processing circuit, Dll * I) u is a demodulating circuit, M, , , M,
, is a modulation circuit, CL.

is the switching circuit that switches from the downlink T main transmission line to the backup transmission line, the turtle is the code receiving circuit, SI is the code transmitting circuit, DO,..., DOl are the output circuits, DI is the input circuit, LC8 is the child clock, TD , is a time code decoder, C
OL1□D, which is a switching circuit for temporarily disconnecting the T and d downlinks from the code receiving circuit R1 for remote monitoring control and connecting them to the time code decoder TD, is connected between the master station 0 and the slave station 1. The main transmission line as the lower 9 line, L12D
is also a backup transmission line as a downlink, Lit
u is also the main transmission line as an uplink, L12υ is a backup transmission line also as an uplink, LII
D g L22D I L21U @Litu is a transmission path between the master station O and other slave stations (not shown).

Note that, normally, a plurality of slave stations 1, 2, . . . are connected radially to the master station 0.

Next, the operation will be explained. Operation processing circuit cp of slave station 1
U scans the state of monitored contacts input to the input circuit D11, such as a protective relay or an auxiliary contact of a circuit breaker, and stores the state. If there is a change in the state of the monitored contact, the address number of the contact and the changed state are passed to the code transmission circuit S1. This is the code transmission circuit S1! It is converted into a serial code in a predetermined format, and the modulation circuit M
1. and M,! (This transmission operation can be carried out arbitrarily from the slave station or by a so-called polling method based on an inquiry from the master station.) The modulation circuits M11 and M convert this into a signal suitable for long-distance transmission, such as a frequency shift ( Frequent
ency 5hitf Keying) signal, and both are transmitted to the master station 0 via the main transmission lines t and 11U and the backup transmission line L12[J. At master station 0,
The demodulation circuits Dotr and DOl2 demodulate the incoming signals into serial code pulses, but the switching circuit CLo1 is always a demodulation circuit. Since it is connected to the 1° side, the demodulation circuit D01.
The output of is passed to the code receiving circuit R81.

The arithmetic processing circuit CPU0 of the master station O reads the received contents Z in response to an interrupt signal from the periodic scanning or code receiving circuit (Lot), and updates the contents of its own storage device when state change data arrives. , output circuit Doo,
The display on the display panel GP is changed through the . In addition, the arithmetic processing circuit CP of the master station O records state changes by the typewriter TW via the typewriter control circuit TC.
Uo also checks the input from the control console CD via the input circuit DIo, and when a command to select or control the device of slave station 1 is issued, the corresponding device address and the state to be controlled (human, off, etc.) are sent. Z encoding and code transmission circuit S. Give to 1. The code transmission circuit Sol converts this into a serial code in a predetermined format, and sends it to the modulation circuit M01 and MoS2.
0 modulation circuits MQ11 and M01! modulates this and transmits it to the slave station 1 via the main transmission line LIID and the backup transmission line L12D, respectively. At slave station 1,
The demodulation circuit L) 18 and Dll demodulate the incoming signal into serial code pulses, but the switching circuit CL1
Since it is connected to the side, it is a demodulation circuit.

The output of is passed to the code transmitter circuit. Arithmetic processing circuit cp
u, is the received content due to periodic scanning or an interrupt signal from the code receiving circuit R3! It performs seven lines of reading, code checking, and decoding, and gives control commands to the corresponding equipment via the output circuit DO, □.

In addition, in the code transmission of the state change from the slave station 1 to the master station 0 and the code transmission of the control command from the master station 0 to the slave station 1, the switching circuit CL0. and switching circuit CL of slave station 1 are always demodulating circuits I)ott and I)tt, respectively.
Since it is connected to the main transmission line Litt, it is always connected to the main transmission line Litt.
Although codes transmitted via u and LIID are used, the main transmission path or its related modulation circuit,
If there is an abnormality in the demodulation circuit, etc., the switching circuit CL0. Or use CLl as a demodulation circuit. By switching to the I or L)tt side, the backup transmission line Lxzu,
A code transmitted via LIID Y can be used. This switching operation is performed by demodulating circuit D0,1 or D
Control can be performed using an abnormality detection signal such as a decrease in the reception level of ll.

The above is the operation of normal remote monitoring control and operation recording, but when recording the operation at the master station O, in the normal operation, data on the time when the state change occurred is not received from each slave station 1. There is no other way than to record in the order confirmed by the arithmetic processing circuit CPLI0, but in cases where the operation of protection devices and equipment is much faster than the code transmission time of the data transmission equipment, such as in power systems, data may be When reaching master station 0, it is no longer possible to accurately determine the order of operations.

To solve this problem, each slave station 1 is provided with a slave clock 2, which is synchronized with the master clock, and when a change in status occurs, the time of the slave clock is also transmitted to the master station. That is, when a contact state change is input to the input circuit DI of the slave station 1 described above, the arithmetic processing circuit epu inputs the address number and state of the corresponding contact as well as the time of the slave clock LC. If it is transmitted to the master station O, the arithmetic processing circuit cpuo of the master station O
H To temporarily store this data in its own storage device, and also collect data from other slave stations 1 for a certain period of time, organize it in the order of the time it was added, and type it out on the typewriter TW via the typewriter control circuit TCi. This allows the operator to know the correct operation time and sequence.

In this case, the master clock MC of the master station O and the slave clock LC1 of each slave station
, . . . must be synchronized with a fairly high precision (for example, within several milliseconds), and the operation for achieving this synchronization will be explained below.

In the master station O, the master clock MC gives an interrupt signal to the arithmetic processing circuit CPU0 10 seconds before the scheduled time. In response to this, the arithmetic processing circuit CPU processes each slave station 1.2. . . , a switching control command for time code reception is passed to the code transmission circuit SOf w SOl + . Code transmission circuit S. 1 e SOl e... receives this, converts it into a serial code in a predetermined format, and sends it to the modulation circuit M.
. 1. , Mo, , , MO, , , Mo, , ,・
・Give it to -. Modulation circuit M0,1. M0□s M(+1
1 e M01! e... is this! Modulate the main transmission line and backup transmission line LIID, L□2D
9L21D * L12! It is transmitted to slave stations 1, 2, . . . via D g .

In the slave station 1, the demodulation circuit D11 and the demodulation circuit D1. The signal that has arrived! However, since the switching circuit CL is connected to the demodulating circuit I)tt side, the output of the demodulating circuit I)tt is passed to the code receiving circuit R8. Arithmetic processing circuit CPU.

reads the code arriving at the code receiving circuit R, and if this is a switching control command for time code damage, the output circuit DO! ! The switching circuit CT and -g are disconnected from the switching circuit CL1 side through 'l, and connected to the time code decoder TD side.

On the other hand, in the master station O, the arithmetic processing circuit CPUo completes the transmission of the switching control command for time code reception (this varies depending on the signal transmission speed, but 0.5 seconds is enough)
, the switching circuits CTos and C are connected via the output circuits DO0 and
Tot*-'l code transmitting circuit 301*%, 1
... and connect it to the time code generator TG.

When the above switching is performed, the time code generated by the time code generator TG is transmitted to the modulation circuit M. ,,,M. □
, ..., and the slave station 1" is modulated by the downlink L120 t L22D e "' of the backup transmission path.
2,... is transmitted. In the slave station 1, as described above, the switching circuit CT is the time code decoder TD.

Since the output of the demodulation circuit Dlt is passed to the time code decoder TD1, the time code is received. The time code decoder TD unlocks its output circuit when more than 5 seconds have elapsed since the start of reception, and when the time arrives on the hour, it outputs a time adjustment pulse to the slave clock LC. In response to this, the child clock LC adjusts its time to the hour. More precisely, it is necessary to take into account the transmission delay time from master station 0 to slave station 1, and the transmission delay time measured in advance! Set to the added time. For example, in the case of a transmission delay time of 0 to 5 msec, when the slave clock circuit LC receives a time adjustment pulse from the time decoder TD around 19:00, it sets the time to 19:00:0005 seconds.

In the master station O, the arithmetic processing circuit CPUo, after a certain period of time,
For example, an interrupt signal from the master clock circuit MC! 15 years since receiving
After seconds, the switching circuit (,'T
O,, CTo, ,...t Separated from time code generator TG and code transmission circuit S. l5SO! *...
Connect to.

Further, in the slave station 1, an arithmetic processing circuit CPU.

After a certain period of time, for example, 15 seconds after reading the switching control command for time code reception from the code transmitting circuit,
It is disconnected from the switching circuit CT and the 4-time code decoder TD through the output circuit DOs2'a' and connected to the switching circuit CL.

Through the above operation, the master clock circuit Me of the master station O and the slave clock circuit LC of the slave station 1 are synchronized (same for slave stations 2 and below), but the time code for synchronization is transferred to the backup transmission line L.
12D*L22D*..., code transmission for remote monitoring and control is transmitted via the main transmission line L.
IID * "ZID *... In a normal state where transmission is carried out via Z, time synchronization can be performed without affecting the remote monitoring control operation at all, and if the main transmission line fails and the backup transmission Only if you are using
Code transmission for remote monitoring control is only interrupted for a certain period of time.

The configuration shown in FIG. 1 includes a master station O and slave stations 1, 2 . It shows the case where the transmission path between ... is radial,
Other slave stations 2 may be connected to the slave station 1 in a chain.

In addition, the master clock circuit MC and time code generator TG
may be structurally integrated, and the signal to the arithmetic processing circuit CPU Uo may be sent via an interrupt, or may be constantly monitored by the arithmetic processing circuit cpu0 via the time code input circuit, and a certain time before the scheduled time. , the switching control command operation 7 for time code transmission and reception may be performed, and the same effect as in the above embodiment can be obtained! play.

〔Effect of the invention〕

As described above, according to the present invention, time synchronization 7 is performed using the backup transmission line that is always in a standby state, so time synchronization 7 can be performed without affecting the operation of remote monitoring control. Even if the main transmission line fails and the backup transmission line is used to transmit codes for remote monitoring and control, you can synchronize the time by simply interrupting it for a certain period of time! What you can do is what you get.

[Brief explanation of the drawing]

FIG. 1 is a block connection diagram of a remote monitoring and control device according to the present invention. 〇 is the master station, 1 is the slave station, LIID y Lllo is the main transmission line, 112D * L12L+ is the backup transmission line, MC is the master clock, TG is the time code generator,
Sl, 501i code transmission circuit, CTo+-CTItl'
l switching circuit, Ro. R1 is a code receiving circuit, TDl is a time code decoder,
LC, is a child clock.

Claims (1)

[Claims] In a remote monitoring and control device consisting of a master station and a slave station connected to the master station via a main transmission line and a backup transmission line, the master station has a master clock and a code that encodes the time of the master clock. and a first switching circuit that temporarily disconnects the downlink of the backup transmission line from the code transmission circuit for remote monitoring control and connects it to the time code generator, and the slave station includes: a slave clock, a time code decoder that inputs a time correction signal obtained by decoding the time code signal from the time generator to the slave clock, and a code receiving circuit for remotely monitoring and controlling the downlink of the backup transmission path. A second switching circuit is provided which is temporarily disconnected from the main station and connected to the time code decoder, and the time code generator and the time code decoder are connected to the backup transmission line by a switching control command from the master station to the slave station. A remote monitoring and control device characterized in that the master clock and the slave clock are synchronized by being connected to each other via the master clock and the slave clock.