Control scheme of the de-icing method by the transferred current of bundled conductors and its key parameters

Transferring the current of bundled sub-conductors through smart switching modules is a promising de-icing method. This study explores the application of line impedance modulation to line de-icing. The control requirements of the de-icing method by transferred current are illustrated according to the characteristics of the method, and two key parameters, namely, critical ice-melting current and ice-melting time, are introduced. The analytical expression for the critical ice-melting current is deduced theoretically. On this basis, the effect of icing shape on the critical ice-melting current is analysed and discussed, along with the calculation of the critical ice-melting current when icing on the windward surface of conductor. A simplified method for calculating ice-melting time is presented on the basis of the heat balance equation during the ice-melting process. With the control requirements of this method as a framework, the calculation and selection of the grouping mode and current duration for the sub-conductors are discussed, and the control scheme of the de-icing method by transferred current is established. The control scheme is preliminarily validated by laboratory investigations conducted in an artificial climate chamber. The results can serve as a reference for obtaining the ice-melting scheme when de-icing via the transferred current of bundled conductors.