JPS61128644A - Information transmitting method in remote monitoring control system - Google Patents

Abstract

PURPOSE:To prevent to reduce a response of the system without making a hardware complicated by increasing the number of information word of one frame to the prescribed number when unstationary information is transmitted. CONSTITUTION:When all set values are transmitted from a control place 10 to a place to be controlled 20, the return is executed to two usual word transmitting modes, and operation starting information including a control word is transmitted to the place to be controlled 20. Receiving this, the system is started to operate based upon a newly received set value at the place to be controlled 20, and the system is switched to two usual word receiving modes. As mentioned above, the transfer of the unstationary information ends and thereafter, a cyclic transmission is repeated by the number of the usual word.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION This invention relates to an information transmission method in a remote monitoring and control system applied to power equipment systems of power generation and substations, for example.

BACKGROUND OF THE INVENTION Information transmission in the conventional power system remote monitoring and control system E is generally carried out by an isitalic transmission method.

In other words, all monitoring information is constantly transmitted to the control center irrespective of whether or not there is a change in the state of the equipment to be monitored and controlled at the control center.

Furthermore, control information created at the control center is also constantly cyclically transmitted to the controlled station.

The cyclic transmission method requires bit synchronization and word synchronization between transmitters and receivers. As a method for synchronizing words, a frame synchronization method with a high transmission rate is adopted.

Furthermore, as a method for synchronizing bits, a frame start-stop synchronization method is often used, which allows synchronization of words and bits to be achieved at the same time. One frame consists of a synchronization word and an information word, and in a general transmission format, the number of information words in a frame is constant.

The problem that the invention aims to solve In remote monitoring and control systems for power systems.

Measured values such as voltage and current, equipment status information, and failure information are cyclically transmitted from the controlled station to the control station.

In addition, control information for circuit breakers, disconnectors, electromagnetic contactors, electric valves, etc. is cyclically transmitted from the control center to the controlled station.

Recently, there is a strong tendency for remote monitoring and control systems to become more sophisticated due to advances in microprocessors and Da engineering technology. In the case of electric power systems, there is a demand for remote control of functions that have not been previously controlled remotely, such as maintenance functions and automatic control functions (voltage regulation, accident recovery). When these functions are remotely controlled, setting items that were conventionally set manually at the controlled station must be transmitted from the control center. In order to transmit such setting information, if the number of information words in the above-mentioned dot-italic transmission is increased, the amount of information per %1 frame becomes very large, and the transmission time increases.

In other words, the period of cyclic transmission becomes large.
1 The negative effects such as a decrease in system responsiveness are significant. The operation of resetting the values of setting items on the controlled station side is performed only sporadically, and there is no need to cyclically transmit setting information at short intervals. Nevertheless, a transmission method that causes the above-mentioned adverse effects is not desirable.

This invention has been made in view of the above-mentioned problems with the conventional technology, and its purpose is to improve the efficiency of transmitting non-stationary information without reducing the normal transmission cycle in the simple click transmission method. An object of the present invention is to provide an information transmission method in a remote monitoring and control system that allows a large amount of information to be easily transmitted within the framework of the basic procedure of the cyclic transmission method.

Means for Solving the Problem Therefore, in this invention, the number of information words in one frame is fixed during normal times, and the information words are used to exchange "notification of increase in number of information words" and "affirmative notification" therefor. After that, the number of information words in one frame is increased to a predetermined number to transmit non-regular information.

Embodiment FIG. 1 shows a schematic configuration of a remote monitoring and control system according to the present invention. The control center 10 includes processing equipment, mainly computers, 11% indicators and indicators.

Monitoring control panel 1 including a recording needle and various switches, etc.
2, a transmitting circuit 13, a receiving circuit 14, and the like are provided. The controlled station 20 includes a processing device 21 mainly including a computer, a receiving circuit 22, a transmitting circuit, a monitoring control target machine M24, and a measuring instrument 25 for measuring current, voltage, etc. related to the target wJ 624. , an auxiliary panel 26, etc., which is used when manually controlling the target device 24, etc., is provided.

The transmitting circuit of the controlled station 20 turns on the imaging equipment 24.
- O'FF information and measurement information by the measuring device 25 are transmitted. This upstream information is received by the receiving circuit 14 of the control center 10 and displayed on the monitoring control panel 12 via the processing device 11. Control information created on the control center side is received by the receiving circuit 22 of the controlled center 20 from the transmitting circuit 13 .

The processing device 21 controls the target device U based on the control information.

Information transmission between the control section to and the controlled station 20 is performed by the cyclic transmission method described above. Also, transmitting circuit 1
3.23 has a parallel-to-serial conversion function.

The receiving circuits 14 and 22 have a tray conversion function, and transmission between them is serial transmission.

@2 Figure (A) shows the transmission format of downstream information from the control station 10 to the controlled station 20. Normally, one frame consists of two words: a synchronization word and a control information word. However, when transmitting the setting information as the above-mentioned unsteady information to the controlled station 20, two words, setting information word I and ■, are added after the control information word of the notification.

FIG. 2(B)'l(0) shows the format of the setting information words I and ■. In this example, since the set value address is 6 bits, a maximum of 64 set values can be transmitted to the controlled station 20. The setting value for one dose is 5 digit BC
It is expressed using the D code.

FIG. 3 shows a transmission control manual for transmitting the above setting information. When attempting to transmit a setting value from the control center 10 to the controlled station 20, first, manually or automatically by the processing device 11, a "setting value transmission notification" is transmitted to the controlled station 20 in a normal transmission format (step ). The normal transmission format is two words: a synchronization word and a control word, and the [setting value transmission notification] is transmitted while being included in the control word. This "set value transmission notification" corresponds to the aforementioned "information word count increase notification".

When the controlled station 20 receives the "setting value transmission notification", it prepares to receive the setting information words 1 and 1, and when the preparation is completed, it sends an "affirmative notification (start OK)" to the monitoring information word in the normal transmission format. and transmits it to the control center 10 (step ■).

When the control center 10 receives the "affirmative notification", it switches the transmission mode, and adds the setting information words l and ■ to the two-word automatic transmission mode of the synchronization word and the control information word. Convert to the 4-word transmission mode, and send the setting information words I, I to the controlled station 10.
It also sends I (step ■). The controlled station 20 receives and stores this, and also uses the setting information word ■ for error detection.

■Controlled by chip commutation transmission method＜+ll place 10
(Step ■). The setting information sent at the control center LO is compared with the information sent back, and if there is an error, retransmission processing is performed. If there is no error, repeat steps ① and ② as many times as necessary to transmit all set values.

Once all set values have been transmitted, the control station IO returns to the normal two-word transmission mode and transmits the "operation start notification" to the controlled station 20, including it in the control word (step 2). In response to this, the controlled station 20 starts operating the system based on the newly received set value and switches to the normal 2-word reception mode.

This completes the non-regular information transmission process, and thereafter cyclic transmission is repeated with the normal number of words.

Effects of the Invention As explained in more detail, the information transmission method in the remote monitoring control system according to the present invention can achieve unsteady transmission without reducing the normal transmission cycle in the simple click transmission method. A large amount of information can be easily transmitted within the framework of the basic procedure of the Knifelick transmission method, so that the hardware does not become particularly complex and the software can be easily modified. The present invention can be practiced in the following manner.

[Brief Description of the Drawings] Fig. 1 is a schematic diagram of a remote monitoring and control system according to an embodiment of the present invention, Fig. 2 is a diagram showing a transmission format of downlink information in the same system, and Fig. 3 is a diagram showing a transmission format of downlink information in the same system. FIG. 3 is a diagram showing a transmission control procedure according to an embodiment of the present invention. 10... Control center, 20... Controlled station, 13.23.
...Transmission circuit, 14.22...Reception circuit.

Claims (1)

[Claims] (1) In a remote monitoring and control system that transmits control information and monitoring information between a control center and a controlled station using a cyclic transmission method using a synchronization word and an information word as one frame, normally the number of information words in one frame is is fixed, and the information word is used to notify the increase in the number of information words.
An information transmission method in a remote monitoring and control system, characterized by exchanging "affirmative notifications" in response thereto, and thereafter increasing the number of information words in one frame to a predetermined number to transmit unsteady information.