What is the future development trend of the IPC industry? In the past, industrial control computers were mainly used in continuous and process control of electrical, coal chemical, and oil chemical; manufacturing automation is mainly used in the production process of discrete processing such as machinery, electronics, and automobiles; stand-alone automation is mainly It is applied to the mechatronics integration of CNC machine tools, intelligent instruments, robots, electric vehicles, frequency conversion motors, electric home appliances, medical equipment and other products. In the future, IPC applications will have new growth points: environmental protection, housing, public works, roads and transportation, construction and communities, agriculture and rural areas.
1. The development trend of IPC technology
The development of IPC and its applications is closely related to the world trend of informatization, digitization, and intelligence, as well as the development of technologies such as computers, control, networks, and displays. The DCS in IPC is greatly influenced by the computer, and the response speed is very fast. The main development trend of digital control system:
1. DCS specialization. In order to better adapt to the application of various related fields, DCS must further understand the process and application requirements of the profession, and gradually form such as nuclear power DCS, substation DCS, glass DCS, cement DCS and so on.
2. For DCS industrial PCs, DCS composed of IPC has become a major trend. PCs have become very common as operating stations or node machines for DCS. PC-PLC, PC-STD, PC-NC, etc. are the pioneers of PC-DCS, and IPC has become DCS hardware platform.
3. DCS is developing towards intelligence. Due to the development of database systems and reasoning skills, especially the application of knowledge base systems and expert systems such as self-learning control, remote diagnosis, and self-optimization, DCS can be realized at all levels. artificial intelligence. Similar to FF fieldbus, microprocessor-based smart devices such as smart I/O PID control, smart sensors, transmitters, actuators, smart man-machine interfaces, programmable regulators, etc. have appeared one after another.
4. DCS is developing towards integration. Due to the development of data communication links and network standardization, various single (multiple) loop regulators, PLCs, industrial PCs, NCs and other industrial control equipment form a large system, which satisfies the requirements of factory automation. Requirements, adapted to the general trend of openness.
二、PLC
There are about 200 PLC manufacturers in the world, and more than 300 varieties are produced. In 1998, 1999 and 2000, PLC shipments were 14.56 million, 16.2 million and 17.78 million, respectively. Since 1995, PLC has been divided by end users: automobile accounted for 23%; food processing accounted for 16.4%; chemical/pharmaceutical accounted for 14.6%; metal/mining accounted for 11.5%; pulp/paper accounted for 11.3%; other 23.6%. With the application requirements of complex and large systems such as CIMS, engineering automation, and process control, the development trends of PLC are mainly as follows:
High function, high speed, large capacity, increase the development direction of analog quantity, and form a large system that can compete with DCS.
The enhancement of network communication capabilities is an important direction for the development of PLC technology. The Ethernetization of the Internet has been successful, and fieldbuses are constantly evolving.
Diversified programming languages IEC61131-3 specifies 5 programming languages: ladder diagram, function sequence diagram, function block diagram, structure diagram.
3. Digital control equipment
Easy to use: Improve the man-machine interface, simplify the program, use symbol keys on the operation panel, and try to use dialogue, etc., to facilitate the user's use.
AC Servoization: The constant power range of the AC servo system has reached 1:4, and the speed range can reach 1:1000, which is basically equivalent to the DC servo. Small size, low price, high reliability AC servo is more and more widely used
Miniaturization: Due to the high integration of semiconductor circuits, the three-dimensional packaging, and the three-dimensional plug-in circuit board, the NC equipment is further miniaturized. In the operating unit of the NC equipment, the CRT is replaced by a TFT color liquid crystal display, a touch screen, etc., and the thickness is only 1/4 of CRT and so on.
Full-featured numerical control system is developing towards integrated automation: In order to meet the requirements of FMS, CIMS, unmanned factories, etc., it is combined with robots, automated cars, and automatic diagnostic tracking and monitoring systems to develop an integrated control and management system. It has become an international numerical control system. Direction of development.
High speed: The so-called "three highs" refer to high spindle speed, fast movement speed and high tool change speed. In order to realize high-speed machining, it is necessary to perform high-speed processing on the spindle. The high-speed speed of the AC spindle motor is 180,000 rpm; the high feed rate is 120 m/min; the tool change speed is 1 s; the acceleration is 2 g.
High efficiency: The key to achieving high-efficiency machining, shortening non-cutting time and machining cycle is to improve the performance of PMC processor. When the processing content is complicated, the programming language of PMC becomes a problem, although C language and PASCAL have been actually used, But in order to replace the ladder diagram language, a visual language like downstream diagram is also needed.
Mechanical intelligence: It is a new technology in the field of numerical control. The so-called mechanical intelligence function refers to the function of self-compensation for mechanical deformation caused by factors such as temperature and mechanical load. These include sensors that detect the spindle load, spindle and machine base deformation, and circuits that process sensor output signals. The sensor itself has a signal processing function, so it is called a smart sensor. AI will be applied to PMC to process the signal.
PCization: With the high development of large-scale integrated circuit manufacturing technology, the PC hardware structure is made small, the CPU runs faster and faster, and the storage capacity is also increasing. Mass-produced personal computers have greatly reduced costs and continuously improved reliability. The opening of computers, the application of Windows, and the application and software development of more technical personnel have made computer software more abundant. The function of the computer is already very powerful, and the CAD/CAM software of the computer is also transplanted from the miniaturization and workstation to the PC, and a three-dimensional graphics display and process data processing system is established on the PC. Therefore, PC has become an important resource and means for CNC system development.
