An optical deformation measurement system for buckling tests on Continuously Transposed Cable (CTC) using high-speed camera recordings and marker tracking is proposed. The aim of the buckling test setup is to analyze the mechanical strength of CTCs with respect to radially acting electromagnetic forces as they appear in power transformers. Therefore a CTC winding arrangement is fed by a short-circuit current while the deformation is recorded by the camera system. The verification of the new deformation measurement system is done by an independent system based on acceleration sensors. Especially operationally aged power transformers can be affected by high short circuit currents, resulting in serious damages on windings. Thus, the influence of ageing phenomena on the mechanical strength of CTCs like degradation of the paper insulation shall be investigated with the proposed system. Experimental results are proposed for a factory-new CTC and the influence of paper insulation on its stiffness is evaluated from the marker tracking results during the short circuit tests.
<p>The short circuit withstand capability of power transformers describes the ability of the windings to withstand electromagnetic forces resulting from current density in the conductors and magnetic stray fields. Especially operationally aged transformers often have a reduced short circuit strength what can lead to irreversible deformation of windings if high fault currents occur. Short circuit strength is to some degree dependent on the mechanical strength of the conductors. Mainly the cellulosic insulation materials experience degradation during operation time due to high temperatures and moisture. Hence a reduction in short circuit strength can be correlated to some degree with the aging of the cellulose. In this paper the influence of paper insulation around Continuously Transposed Conductors (CTC) on their mechanical strength will be analyzed by a simplified analytical model as well as by a FEA based mechanical simulation model.</p>
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.