The Benefits of Soft Sensor and Multi-rate Control for the Implementation of Wireless Networked Control Systems

• Grant number: 14/24353-2
• Support Opportunities: Regular Research Grants - Publications - Scientific article
• Start date: December 01, 2014
• End date: May 31, 2015
• Field of knowledge: Engineering - Electrical Engineering
• Principal Investigator: Eduardo Paciência Godoy
• Grantee: Eduardo Paciência Godoy
• Host Institution: Universidade Estadual Paulista (UNESP). Campus Experimental de Sorocaba. Sorocaba , SP, Brazil

Abstract

Recent advances in wireless networking technology and proliferation of industrial wireless sensors have led to an increasing interest in using wireless networks for closed loop control. The main advantages of Wireless Networked Control Systems (WNCSs) are the reconfigurability, easy commissioning and the installation in places where cabling is impossible. Despite these advantages, there are two main problems which must be considered for practical implementations of WNCSs. One problem is the sampling period constraint of industrial wireless sensors. This problem is related to the energy cost of the wireless transmission, once power supply is limited, which unable the use of these sensors in several closed-loop controls. The other technological concern in WNCS is the energy efficiency of devices. As the sensors are powered by batteries, it is expected the lowest possible consumption to extend battery lifetime. As a result, there is a compromise between the sensor sampling period, the sensor battery lifetime and the required control performance for the WNCS. This paper develops a model based soft sensor to overcome these problems and enable practical implementations of WNCSs. The goal of the soft sensor is generating virtual data allowing an actuation on the process faster than the maximum sampling period available for the wireless sensor. Experimental results shown the soft sensor as a solution to the problem of sampling period constraint of wireless sensors in control applications, enabling the application of industrial wireless sensors in WNCSs. Additionally, results demonstrated the soft sensor potential for implementing energy efficient WNCS through the battery saving of industrial wireless sensors. (AU)