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Synchebueno GPS Clock in Korean Hydraulic Pump Station

 

With the rapid development of computer and network communication technology, industry automation system of digital and network era has arrived. This aspect for the data exchange between control and information systems, analysis and application, on the other hand, provides a better platform for all kinds of labels on the accuracy of the real-time and historical data time also put forward higher requirements, using price inexpensive GPS clock to unify all kinds of system clock, is currently the major systems used in the design of standard practice. Such as large distributed control system (SCADA), auxiliary system programmable controller (PLC), ChangJi monitoring information system (SIS), station management information system (MIS) of the master clock by suitable GPS clock signal interface, get the standards of TOD (minutes) when (date) (month) (year), and then according to their respective clock synchronization mechanism, will be in the system from the clock error is limited to a small enough range, so as to achieve the clock synchronization of the whole system.

1, an overview of the Project

Hydraulic pump station automation information acquisition system SCADA function for the dispatcher, set pump controller provides the real-time data and information, and can make them easy to repeat or accident history data and information query. In system design, the need to consider more is network structure, communication protocol conversion, data storage medium and satisfy the requirement of the SCADA function several performance indexes, without taking into account the system so what is the impact of the clock is not synchronized. Because the system so the clock out of sync will cause some of the more special fault, such as data and information loss, SOE event information logic chaos, some workstation crash even system paralysis, so in order to eliminate the influence of the clock out of sync, it is necessary to analyze the clock synchronization in the important functions of SCADA system and the realization of a variety of ways.

The strong pumping station SCADA system is a real-time system, it collect real-time data and information of various pumping stations, after dealing with the software and hardware, the display data and information in each pump station or stored in the history database. SCADA system is divided into general control end system and each pump station system, so the entire network clock synchronization according to two parts:

(1) the total control end system each work and clock synchronization server;

(2) each pump station system master control unit and intelligent unit of clock synchronization;

2, the total control system clock synchronization

Total control end system each workstation, with the purpose of the master server clock synchronization is to ensure that data operations such as add, change, delete the consistency and completeness of the entire network. Inconsistencies and incomplete data will cause the main case system switch or historical data for storage, can not correctly identify the data consistency and integrity, resulting in the loss of information and data, even lead to paralysis of the system. Due to various workstations and servers crystals chip for a long time after the operation, there will be a clock no problem due to leakage or other reasons, and take the corresponding ways to implement the total control system network clock synchronization, the specific way as shown in figure 1: general control end system clock synchronization methods generally adopt the way of figure 1, because K806 model GPS clock device can not only provide a network interface can also provide multiple network interface (NTP), in addition to implementation with GPS clock synchronization, also need not all servers, workstations and front machine run other processes, you just need to will start NTP service system, thus greatly save the system resources.

3, the pump station system clock synchronization


Pump station system and general control end system clock synchronization and pumping station clock synchronization between each smart devices, is to ensure that the data can be gathered by the interval of intelligent information, after treatment, the total control system can correct the time of the repeat data or information, order and logical relations. Operator, set controller according to the display of data and information, real-time grasp the operating state of the pump station system at a time, to ensure the safety of economic operation, scheduling.

Each pump station system workstations using dedicated clock synchronization network clock synchronization, so that we can improve the accuracy of clock synchronization, and convenient, while reducing the resource burden of intelligent units, each unit pump system in the intelligent adopts figure 2 clock synchronization method, through a serial port or we K806A type products for intelligent units clock synchronization pulse interface.

4, product topology

The system clock synchronization is divided into two parts, one is always charged with the client and pumping station we K806C model is recommended for the NTP server clock to implement, the other is a pumping station of intelligent unit and acquisition unit (PLC) we recommend using K806A type serial satellite clock, specific as follows: