2SCADA system architecture
SCADA (SupervisoryControlAnd DataAcquisition) system, that is, data acquisition and monitoring control system, is a computer-based remote automation monitoring system. The SCADA team is used to address remote data collection and monitoring and control, as well as process control, including industrial plant and city and inter-city geographic distribution.
2.1 Remote communication requirements
To achieve drainage, well group, moisture, drainage, water diversion and other projects, automatic monitoring of pumping station equipment, centralized dispatch management, real-time collection of various water conditions, work data is the basis of information construction.
At present, most of the pumping stations in operation in China were built in the 1960s and 1970s. Due to the limitations of technology, capital and equipment at that time, most pumping stations still use traditional manual management and operation methods, which have been aging for many years. Disrepair, coupled with the shortage of maintenance engineers, the overall quality is low, resulting in increasing energy consumption of pumping station equipment year by year, the efficiency of irrigation and drainage is sharply reduced, and the social and economic development needs of building a socialist harmonious society cannot be guaranteed. These problems have attracted the attention of central and local governments at all levels. The construction of pumping stations and large-scale renovation have entered a new historical period.
In order to further improve the level of automation facilities of pumping stations, industrial automation products such as programmable controller PLC, industrial control computer IPC, human-machine interface HMI and industrial field bus are widely used in the construction and transformation of pumping stations. However, in the networking process of pumping station equipment, the construction of communication lines still stays at the level of laying special communication cables or adopting GPRS wireless communication technology.
The disadvantages of laying a dedicated communication cable are high construction cost, high energy consumption, long time consumption, and the inability to construct communication cables in many special environments, which restricts the level of construction and automation of the pump station. GPRS wireless communication technology has small data transmission and slow response, which can not meet the requirements of real-time control, video surveillance, online program download and diagnosis.
2.2 Drainage pump station informationization dilemma
(1) At present, most of the application systems are information inquiry services, and the data is not comprehensive. There is no professional information system for visual management and scheduling of urban drainage and river water flow. It is impossible to realize the early warning mechanism of crisis system, and analyze the real-time data collection of control system. Processing, judging system operation, and recording system real-time data. When the system analyzes and judges the equipment fault according to the collected data, the controller automatically runs the protection program, emits an audible and visual alarm signal and generates a report, and transmits it to the remote central control system through the remote safety communication system. When the technician removes the fault of the field device, the controller automatically resumes the system operation according to the operator's operation signal. At present, advanced control systems can classify fault information into various departments according to system fault levels and classification.
The important role of early warning is the continuous improvement of the intelligent analysis system in the remote central control. After collecting the important parameters of the port machinery equipment on site, it can analyze through intelligent algorithms and experience, and provide early warning of the system's security risks. Repair, avoiding safety hazards and becoming serious safety accidents;
(2) The number of monitoring stations and points is insufficient, and the layout cannot meet the actual needs of daily and flood control dispatching. There is no timely and accurate monitoring means for rivers, drainage pumping stations, pipe networks and other facilities that are prone to occur and have occurred in flood seasons. At the same time, emergency portable monitoring equipment is lacking. The control system includes the host computer, PLC, and engineering inverter. When the fault occurs, the core is not only the PLC on the small and medium-sized equipment, but the diagnosis needs to be comprehensive, including the host computer, PLC, and engineering inverter. The PC software used in these systems is different. The tools can be taken to the site for diagnosis. However, if a remote maintenance engineer arrives at the site in the event of a fault, the longer the time, the safety and personal safety of the product will be brought. The greater the likelihood of a security incident, the need for remote diagnosis and maintenance is particularly urgent. Remote diagnosis must be done in the same way as the engineers at the site, such as in-depth PLC program online, inverter parameter display and control, real-time configuration and diagnosis of the host computer.
(3) Although some drainage pump station management units have realized automatic collection and storage of some data, some systems have long construction time, data dispersion, technical level and standards are not uniform, and each system runs independently, and data is not shared. Can not provide strong service support for the upper application system.
