%0 Journal Article
%T Real Time Implementation of Incremental Fuzzy Logic Controller for Gas Pipeline Corrosion Control
%A Gopalakrishnan Jayapalan
%A Ganga Agnihotri
%A D. M. Deshpande
%J Advances in Fuzzy Systems
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/203739
%X A robust virtual instrumentation based fuzzy incremental corrosion controller is presented to protect metallic gas pipelines. Controller output depends on error and change in error of the controlled variable. For corrosion control purpose pipe to soil potential is considered as process variable. The proposed fuzzy incremental controller is designed using a very simple control rule base and the most natural and unbiased membership functions. The proposed scheme is tested for a wide range of pipe to soil potential control. Performance comparison between the conventional proportional integral type and proposed fuzzy incremental controller is made in terms of several performance criteria such as peak overshoot, settling time, and rise time. Result shows that the proposed controller outperforms its conventional counterpart in each case. Designed controller can be taken in automode without waiting for initial polarization to stabilize. Initial startup curve of proportional integral controller and fuzzy incremental controller is reported. This controller can be used to protect any metallic structures such as pipelines, tanks, concrete structures, ship, and offshore structures. 1. Introduction Natural gas (NG) transportation pipeline network systems are similar to national power transmission networks and are used for transporting natural gas (NG) across a country for thousands of miles from different source stations to multiple destinations. This underground insulation coated iron pipeline network is operating at a high pressure of 90£¿bars. Corrosion is a phenomenon by which metal is oxidized and etched away naturally contributing to material loss. Corrosion of this pipeline leads to reduction of wall thickness and the design life of the pipelines, gas leakages, environmental pollution, fire hazards, and gas supply disruption. This may lead to major manmade disasters like gas transportation pipeline explosions. Corrosion reduces the life of metal structures, oil and gas transmission underground and undersea pipelines, storage tanks, offshore platforms, and so forth. Corrosion is an electrochemical process. It can be controlled by impressing current in gas pipeline (which acts as cathode of corrosion cell). Basics on pipe to soil potential measurement (PSP) and design details on pipeline corrosion control by impressed current cathodic protection (ICCP) method are available in [1]. Conventional transformer rectifier (TR) units which are used in cathodic protection (CP) system uses multitapped secondary transformer [2]. Precision regulation at output is not
%U http://www.hindawi.com/journals/afs/2014/203739/