JPH0954176A - Central monitoring control system time correction method - Google Patents

Abstract

(57) Abstract: A time adjustment method for a central supervisory control system that improves the reliability of control and monitoring performed using the time of a remote station. SOLUTION: The time data of the center device is transmitted to each remote station, and the time data received by each remote station is returned as it is, thereby measuring the transmission time between the center device and each remote station, respectively. Performs each measured value until each remote station adjusts the time, calculates the average transmission time for each remote station, and transmits this average transmission time from the center unit to each remote station. Since the current time is calculated from the time data of the local station and the average transmission time between the local remote station and the center device, the time of the local remote station is adjusted. Becomes smaller and uses the time of each remote station Reliability for the control and monitoring performed is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a central supervisory control system equipped with a center device and a remote station, and the remote control is based on the time data of the center device and the average transmission time between the center device and each remote station calculated by the center device. The present invention relates to a time adjustment method for a central supervisory control system that adjusts the time of a station.

[0002]

2. Description of the Related Art Generally, a central supervisory control system includes a center unit and a plurality of remote stations. The center unit transmits only time data of its own station to each remote station, and each center station receives the time data of the center unit. The time data of the local remote station is corrected using the time data as the current time. For this reason, the times of the center device and each remote station may be greatly different, and a time error occurs in the control and monitoring performed using the time of each remote station.

[0003]

As described above, in the conventional central supervisory control system, each remote station adjusts the time of its own remote station by using only the time data from the center device. The time delay caused by the data transmission from the to each remote station was not taken into consideration. Therefore, since the time of each remote station is delayed from the time of the center device by the transmission time at the time of time adjustment, the error at the time of time adjustment caused by this data transmission is reduced, and the control is performed using the time of the remote station. Also, it is necessary to reduce the time error that occurs during monitoring to improve its reliability.

The present invention has been made in view of the above circumstances, and its purpose is to control and monitor by using the time of the remote station by minimizing the time delay caused by the data transmission from the center device to each remote station. It is an object of the present invention to provide a time correction method for a central supervisory control system that improves the reliability of

[0005]

In order to achieve the above object, according to claim 1 of the present invention, in a time correction method of a central supervisory control system comprising a center device and a remote station, the time of the center device is its own station. By transmitting data to each remote station and returning the time data received by each remote station as it is, the transmission time between the center device and each remote station is measured, and each measured value is measured for each remote station. Buffer the measured values until the remote stations calibrate the time, calculate the average transmission time for each remote station, and calculate the time data of the center device and the average transmission time for each remote station. From the device to each remote station, each remote Station is characterized and time data of the center apparatus, to perform the time correction of the own station remote station by calculating the current time from the average transmission time between the center unit and the local station remote station.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a time correction method for a central supervisory control system of the present invention. As shown in the figure, the central supervisory control system 1 of the present invention comprises a center device 2 and a plurality of remote stations 5 _{1 to} 5 _n . Center apparatus 2 and a mean transmission time calculating function 3 calendar function 4, the average transmission time calculating function 3 transmits the time data of the center apparatus 2 to the remote station 5 ₁ to 5 _n, the remote station 5 ₁ to 5 _{From the} time data returned from _n , the transmission time between the center device 2 and each remote station 5 _{1 to} 5 _n is measured, buffered for each remote station 5 _{1 to} 5 _n , and this buffered remote station With the function to calculate the average transmission time for each remote station from the transmission time,
Each remote station 5 ₁ to 5 _n times the average transmission time of the center apparatus 2 times and the remote each station when correction of has the function of transmitting to each remote station 5 ₁ to 5 _n.

Further, each remote station 5 _{1 to} 5 _n
The arithmetic and function 6 ₁ to 6 _n to return the time data transmitted from the center apparatus 2 to the center device 2 as it is, the time data of the center apparatus 2 transmitted from the center apparatus 2 during time correction of remote stations The current time calculation functions 7 _{1 to} 7 _n , the time correction function 8 ₁ to 8 _n that calculates (corrects) the current time from the average transmission time between the local station remote station and the center device 2, and the calendar function 9 ₁
Have ~ 9 _n . Further, a transmission device that enables transmission between the center device 2 and each of the remote stations 5 _{1 to} 5 _n is provided.

Next, the time correction method of the central supervisory control system of the present invention will be described. The center device 2 transmits the time data of its own station to each remote station 5 _{1 to} 5 _n, and the time data of the center device 2 received by each remote station 5 _{1 to} 5 _n is returned as it is,
Center apparatus 2 measures the transmission time to each remote station 5 ₁ each to 5 _n, they remote station 5 ₁
Buffer every ~ 5 _n . This measurement of the transmission time is carried out several times until the time adjustment of each remote station 5 _{1 to} 5 _n is performed, and the average transmission time of each remote station 5 _{1 to} 5 _n is calculated from the buffered data. Center apparatus 2 transmits the time data of the own station during a time correction of the remote stations 5 ₁ to 5 _n, the average transmission time of the remote station 5 ₁ each to 5 _n previously calculated in each remote station 5 ₁ to 5 _n . Each remote station 5
_{1 to} 5 _n calculate the current time from the received time data of the center apparatus 2 and the average transmission time between the remote station of the own station and the center apparatus 2, and calibrate the time of the own station, thereby It is possible to make the difference between the time of 2 and the time of each remote station 5 _{1 to} 5 _n small.

Therefore, according to the present embodiment, by making the error between the time of the center device 2 and the time of each remote station 5 _{1 to} 5 _n small, the time of each remote station 5 _{1 to} 5 _n is used. The reliability of the control and monitoring performed can be improved.

[0010]

As described above, according to the time renewal method of the central supervisory control system of the present invention, by configuring the time of each remote station, the difference between the time of the center device and the time of each remote station is minute. Therefore, it is possible to improve the reliability of control and monitoring performed using the time of each remote station.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a central supervisory control system to which the present invention is applied.

[Explanation of symbols]

1 ... central monitoring and control unit, 2 ... center apparatus, 3 ... calendar function, 4 ... average transmission time calculating function, 5 ₁ to 5 _n ... remote station, 6 ₁ to 6 _n ... time data return function, 7
_{1 to} 7 _n ... Current time calculation function, 8 ₁ to 8 _n ... Time correction function, 9 _{1 to} 9 _n ... Calendar function.

Claims (1)

[Claims] 1. A time adjustment method for a central supervisory control system comprising a center device and a remote station, wherein the center device sends time data of its own station to each remote station, and the time data received by each remote station is returned as it is. By measuring the transmission time between the center device and each remote station, each measurement value is buffered for each remote station, and the measurement value is measured until each remote station calibrates the time. The average transmission time of each remote station is calculated, and the time data of the center device and the average transmission time of each remote station are transmitted from the center device to each of the remote stations. Data and
A time correction method for a central supervisory control system, characterized in that the current time is calculated from the average transmission time between the local remote station and the center device to correct the time of the local remote station.