Authors: Arun Kumar Paul
Addresses: Fiona 1602, Hiranandani Estate, Thane (W) 400607, Maharastra, India
Abstract: Unlike most control systems, a single arc welding controller performs different welding functions using dynamics of different arc characteristics meeting complex output characteristics - that includes apart from joint characteristics are arc light intensity, fumes and particulate matters, etc. Moreover, unavailability of feedback in major loop for control of heat input to joint divides the parameters of the complete process into external and intrinsic ones. Intrinsic parameters define arc characteristics. Dynamic non-linear intrinsic parameters cannot be made insensitive even through sliding mode control. Representative dynamical systems for starting, stopping and normal welding are also different. This article explores the scope of practical implementation of SMC to complete range of arc welding process. In constant current (CC) manual arc welding process, arc is extinguished by increasing the arc length much beyond the controller can sustain. In that process, it produces large unusable heat causing discomfort to the welder and co-workers. The present article, as well, discusses implementation mechanism of SMC to optimise arc light intensity and reduce heat generation in arc column in order to convert mechanism of manual arc extinction of SMAW welder friendly. Chattering issue is not important.
Keywords: dynamic control; intrinsic control parameters; arc welding; health hazards; discomfort level control; multiple-structure VSS; variable structure systems; power electronics; soft SCM; sliding mode control; lateral SCM; VSS compatibility; soft switching; arc light control.
International Journal of Power Electronics, 2012 Vol.4 No.5, pp.409 - 432
Received: 09 May 2012
Accepted: 14 Jul 2012
Published online: 08 Jan 2013 *