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Taking continuous process as an example, the industrial production process control system has developed from process heat control to on-line monitoring of product quality and dynamic detection of equipment operation. Monitoring of production status and coordinated control between equipment. The new industrial control system is more aimed at metallurgy and oil refining from the perspective of large systems. Electricity, oil. Designed for continuous production of chemicals, building materials, etc. With the process requirements of high temperature, high pressure and high speed, automation system has become the guarantee to ensure safety. Protect the environment. Important equipment for saving energy, reducing consumption, improving quality and increasing efficiency. Many production links are incompetent by manpower, and non-automation is not enough to ensure safety and quality. They not only deal with single parameter systems, but also deal with nonlinear problems, time-varying parameter problems and stochastic process control problems. Classical control theory, the regulating system based on analog quantity can no longer meet the production needs, and it is replaced by modern control theory based on state space method, and more digital systems combining digital and analog are adopted, such as distributed system, decentralized system and new generation programmable control system. The system consists of industrial control computer and two-way multivariable digital communication realized in recent years. And download the control loop to the basic fieldbus technology. The key technological innovation projects supported by 1999 are as follows:

1. Fieldbus technology Since the appearance of distributed control system (DCS), the concept of Fieldbus has been brewing. It is the product of the combination of automation technology, computer network technology and instrument technology, which will change people's accustomed control mode. For the industrial automation equipment industry, this is a fundamental change and also brings new development opportunities. The field bus control system realizes the full digitization between the field instrument and the control room. Two ways. Multi-station communication overcomes the defects of closed system and makes the control function completely downloaded to the site, becoming a new generation of fully distributed system. Its characteristics are: openness. Decentralized and all-digital communication. The system has a broad market prospect and can greatly improve the technical level of industrial production process control. This year's main support:

(1) Develop new field instruments and equipment, including high performance and multivariable. Multifunctional field intelligent transmitter, intelligent actuator and communication connection products;

(2) Development of system configuration software and portable bus splitter based on fieldbus control system;

(3) As a special control device of the field bus network node. Development of data acquisition device;

(4) Developing low-cost field bus system and equipment (application: grain. Grain storage system, vegetables and medicinal materials in modern agriculture. Flower planting environment detection and control system);

(5) Development of control and operation software based on OPC technology;

(6) Network technology of fieldbus control system.

2. A new generation of industrial control computers

PCI local bus originated from Inter company, and its full English name is peripheracomponent1nterconnect. It is a high-performance 32-bit and 64-bit bus with address and data multiplexing function. It solves the bottleneck problem of processor and display equipment, meets the needs of graphics-oriented operating system and application, and not only meets the needs of high school, middle school and high school. The application of low-end desktop needs also adapts to the needs of all fields from mobile computers to servers.

Compact PCI (compact peripheral component interconnect) means "solid PCI". It is the electrical and software of PCI bus plus Eurocard, which has the ability to take out and replace components without shutting down the system. The realization of "plug and play" function is very important for high availability systems and fault-tolerant systems. Compact PCI can use other existing bus products, such as STD, VME, 1SA, etc. , expand its function, realize * * * storage, and has good accommodation. This year's main support:

(1) Developing and researching Compact PC 1: From STD bus, industrial PC, that is, the latest Compact PCI technology, it is not difficult to see that the development and innovation of industrial control computers in China should absorb and inherit the development experience of software and hardware of commercial computers and take the road of compatibility with commercial computers.

(2) Absorb the characteristics and advantages of Compact PCI technology, and develop chassis and motherboard suitable for market demand; (For example: 3U, 6U chassis, "integrated" CPU board)

(3) Using compact PCI specification and intelligent 1/O template, through system integration, control systems suitable for various fields are respectively combined;

(4) In order to adapt to the application of Windows graphics software technology, the driver corresponding to the hardware is developed;

(5) Develop or quote control software with good function and low cost, and give full play to the advantages of compact PCI, such as compact structure, vibration resistance, good heat dissipation and suitability for embedded applications.

3. Real-time intelligent control software Up to now, the most advanced and effective control system in the world is human beings themselves, so it is an important way to solve the difficult problem of industrial process control to study the control mechanism expressed by human beings and imitate it with the operation of software. At present, the introduction of intelligent control software in industrial production process control system is mainly aimed at nonlinearity, large lag and variability. Uncertain and even rough and unmodeled production process. Because these processes are difficult to control, traditional classical control methods are difficult to work. Because the complicated production process is not well controlled, the energy consumption and quality of production are not improved, and the production is not stable enough. Therefore, it is an effective and feasible way to develop intelligent control in China. According to the current situation of industrial production process control in China, the key support this year is:

(1) Real-time intelligent control software package, including: fuzzy controller and simulation intelligent control software package, providing corresponding interfaces embedded in control configuration software of DCS and other control devices;

(2) Software package for online operation optimization of various production devices and key equipment in oil refining, chemical industry, metallurgy and building materials;

(3) Advanced control software packages such as multivariable predictive control and multivariable intelligent coordinated control;

(4) Software package for fault diagnosis of key equipment.

4. Real-time intelligent control software platform tools In order to help and support the development of real-time intelligent software, small and medium-sized scientific and technological enterprises with conditions hope to develop engineering real-time intelligent control software platform tools with independent intellectual property rights. This year, they will focus on supporting:

(1) fuzzy control development platform; Using CAD method, engineers are supported to develop fuzzy control, from the establishment of membership function, the generation of planning library, the selection of various reasoning methods and the definition of methods. The control algorithm can be directly generated and embedded into other conventional controls only by graphic configuration.

(2) Expert system development platform; Support the whole expert system development and generation cycle, support various reasoning methods and mechanisms, develop graphical configuration, and integrate well with conventional control.

(3) Neural network development platform.

It supports sample data collection/input, selection of various network models, graphical monitoring and training process, automatic generation of neural network control algorithm, and can be integrated with conventional control. It must be pointed out that the engineering application of intelligent control must be combined with conventional control methods (loop adjustment, logic interlocking, picture monitoring, etc.). ) is the most effective method.

5. High-precision modular intelligence 1/0 technology.

In the existing industrial production process control system, the main monitoring part (industrial computer) is generally placed in the control room far away from the scene, and the field measuring instrument (temperature. Stress. Signals (4.20mA) output by locators or transmitters such as flow and speed are transmitted to the control room through multiple parallel cables and connected to the corresponding industrial computers. The industrial computer converts analog signals into digital signals through templates or modules (AO transformation); On the contrary, digital signals can be converted into analog signals (D/A conversion). If the electric signals output by the field instruments can be transmitted by local digital signals, or the upper digital signals can be transmitted to the field and then converted into analog signals and input into the instrument equipment, then a large number of field instruments and industrial computers in the control room can be interconnected by several twisted pairs to complete the functions of the traditional control system, thus reducing the cost, facilitating maintenance, improving the reliability of the system and reducing the area of the control room. This is the intelligent 1/0 technology and field measurement and control network technology for various existing traditional control systems. This year's main support:

(1) Develop an intelligent 1/O module composed of intelligent unit (single chip microcomputer, DSP), 1/O circuit, network connection and corresponding software. Single chip microcomputer and DSP should choose appropriate and advanced 1/O circuits, including common types of A/D, D/A, v/F and DI/DD; Isolated type and non-isolated type.

(2) Developing a measurement and control system consisting of intelligent 1/O module, on-site measurement and detection network, management computer and corresponding software; The smart (0) template can be a single input or output function or a loop control function of a self-closing circuit. The measurement and control network can be a single type or a mixture of multiple networks.

(3) Research and popularize the application of intelligent 1/O module in non-industrial production process, such as the automatic charging system for urban electricity meters, gas meters, hot water meters and cold water meters; Microcomputer protection system for feeder in electrified railway substation.