“PROFIBUS is a field bus technology used for factory automation workshop level monitoring and field device level data communication and control. The distributed digital control and field communication network can realize the monitoring from the field equipment level to the workshop level, thus providing a feasible solution for realizing the comprehensive automation of the factory and the intelligentization of the field equipment. Profibus field bus redundancy technology is a technology that improves reliability through dual profibus ports.
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1 Overview
PROFIBUS is a field bus technology used for factory automation workshop level monitoring and field device level data communication and control. The distributed digital control and field communication network can realize the monitoring from the field equipment level to the workshop level, thus providing a feasible solution for realizing the comprehensive automation of the factory and the intelligentization of the field equipment. Profibus field bus redundancy technology is a technology that improves reliability through dual profibus ports.
An electric actuator is a driving device that uses electricity and converts control signals into corresponding linear or rotary motion through a motor. The Electronic control part of the Keyuan SY series integrated electric actuator includes position feedback device, torque sensing device, motor drive and protection device, logic control device and digital communication module, etc. These devices are all installed in the actuator in a compact electrical in the control box.
Implementing profibus fieldbus redundant communication interface on the electric actuator is beneficial to integrate the electric actuator into the profibus fieldbus control system and improve the communication reliability.
2. Overall design of electric control of profibus redundant bus actuator
Figure 1: The overall design of the electronic control of the Profibus redundant bus-type actuator
The overall design of the electronic control of Keyuan SY series PROFIBUS DP redundant bus type electric actuator is shown in Figure 1 above. SY series electric actuator adopts the scheme of dual processor division of labor and cooperation.
One processor is called the actuator control processor, which is responsible for input signal processing, Display and status indication processing, control of motor drive and protection modules, position feedback (encoder), torque sensing device, and communication with another processor. Control and processing of executive agency tasks.
Another processor is called profibus communication processor, which is responsible for dual redundant profibus bus communication. The control commands from the field bus control system (PROFIBUS master station), the actuator data, status, alarm and the setting and modification of the actuator parameters that need to be sent to the profibus master station are all handled by the profibus communication processor.
3. Profibus redundant bus communication design
Figure 2: System Redundancy
Figure 3: Flying Redundancy
For profibus redundant slaves, the profibus slave redundancy specification must be observed. The Profibus slave redundancy specification specifies two redundancy methods, namely System Redundancy (SR redundancy) as shown in Figure 2 and Flying Redundancy (FR redundancy) as shown in Figure 3.
Keyuan SY series profibus DP redundant bus-type electric actuators support both redundant methods. If the profibus field bus control system supports SR redundancy (for example, Siemens CPU 400-H series products), connect the actuator to the control system according to the SR redundancy mode, as shown in Figure 2. At this time, the two bus interface addresses of the profibus DP redundant bus type actuator of Keyuan are equal (#m=#n). When the interface of the Primary Slave (master slave) is damaged or the communication cable of the master slave is interrupted, the SR redundant The redundant master station sends the parameterized command for channel switching. After the redundant slave station receives the parameterized command for channel switching, it automatically switches the Backup Slave (standby slave station) to the Primary Slave. The switching process is seamless and will not cause I /O loss of data.
If the profibus field bus control system supports FR redundancy, the actuator will be connected to the FR system according to the connection method shown in Figure 3. The two interfaces of the redundant slave station are connected to the same bus. At this time, the addresses of the two bus interfaces of the profibus DP redundant bus type actuator are not equal (#m≠#n), and the address of the Primary Slave should be less than 62 , the address of the Backup Slave is the address of the Primary Slave + 64.
If the profibus redundant bus control system supports parameterized command switching, the redundant slave station will switch according to the parameterized command; if the profibus redundant bus control system does not support parameterized command switching, the redundant slave station will judge whether it needs to be switched. .
4. Summary
With the further improvement of automation technology, Profibus redundant bus control system will be further popularized and used. Keyuan SY series profibus redundant bus-type electric actuators can be perfectly integrated with the profibus redundant bus control system, maximize the advantages of profibus fieldbus, improve the communication reliability and maintainability of electric actuators, and save wiring costs for customers And later maintenance costs, thereby improving the core competitiveness of electric actuator products.
The Links: SKKD380/18 7MBR50SA060