The Research Of The Industrial Ethernet POWERLINK Time Slot Control Strategy

With Fieldbus technology was applied to the field of industrial automation control, the industrial automation present a trend which is from low to high speed and low precision to high precision, the centralized control to distributed control and is proposed an technology which is based on Ethernet technology to realize the fieldbus technology, thus was born the real-time industrial Ethernet technology. Thereinto, because the high real-time bus POWERLINK without professional ASIC chip, and open all source, so the high real-time industrial Ethernet POWERLINK is the developing relatively quickly one.In this paper, we study the control strategy of the industrial Ethernet POWERLINK, and analysis of all kinds of the characteristics and the existence insufficiencies of the control strategy of POWERLINK original time slot, and according to the original time slot control strategy to optimized, respectively puts forward the modified way and optimize the implementation scheme of the time slot in synchronous and asynchronous, to make the strategy is suitable for industrial Ethernet POWERLINK current distribution of master-slave communication mode, and does not change the original POWERLINK link layer structure of the network. The optimization model in the Time slot in synchronous phase is proposed to use the original SCNM polling time slot and PRC time slot combination, based on improving the system time synchronization to calibrate and analyse the conflict node, and in the guarantee conditions for the robust stability of the system to improve system real-time performance. Time slot in asynchronous phase optimization model using a half open system, in asynchronous POWERLINK node to accept the master node scheduling, the multiple asynchronous POWERLINK nodes can send data in the same period, while maintaining the original nature of the network under the premise of making asynchronous POWERLINK nodes can join the network in the process of system operation, and ensure that the original POWERLINK device to work properly, make not to join the network at the same time with the original POWERLINK device performance and POWERLINK network performance.POWERLINK experiment platform, realizes the POWERLINK master-slave network, and optimize the network based on the data frame and object dictionary changes into the POWERLINK network, complete the experiment and design verification plan, after optimization is obtained by analyzing the experimental data slot is better than before with the time slot.Thus increase the control strategy of the industrial Ethernet POWERLINK time slot and real-time industrial Ethernet POWERLINK provides compatibility optimization, and effectively improve the POWERLINK real-time and stability of the network, it has important significance and practical value for the application and the research of the POWERLINK in the field of industrial control.