Wireless critical process control in oil and gas refinery plants

Wireless telemetry systems are now becoming a relevant topic in the field of critical process control in industrial plants and oil/gas refineries. In contrast to wireline communication, wireless links are inherently unreliable. This unreliability depends critically on the propagation environment of the radio-links as the layout of scattering objects (pipes and metallic structures) influences the strength and the fluctuations of the received signal power. The development of next generation critical process control systems using the wireless technology calls for the design of advanced network architectures. By following the guidelines introduced by recent standardization, this paper proposes a novel architecture based on the most recent technological advances to enable wireless advanced process control for tight closed loop applications. Cooperative network paradigm is indicated as the key technology to provide link reliability even in critical environments. A cooperative link-layer protocol has been developed and tested over a IEEE 802.15.4 compliant radio network deployed in non line-of-sight (NLOS) propagation environment with dense metallic obstacles. Test-bed measurements evaluate experimentally the benefits of the cooperative architecture.