A Multi-Functional De-Icing Equipment Using Hybrid Type Parallel Current Source Converters

Abstract

This paper has proposed a phase controlled and PWM controlled power current source converter (CSC) for transmission line de-icing. The proposed system consists of a high-power thyristor-based line commutated converter to contribute a majority of the dc de-icing current and a low power PWM CSC to provide a part of the dc de-icing current and to compensate the low order harmonic ac current from the TCR. Thus, the grid current can be highly sinusoidal. In order to avoid the resonance caused by the interaction between TCR and PWM CSC, a virtual impedance control is implemented in the PWM CSC without using any additional sensors. Comprehensive verification results have been obtained to validate the correctness of the proposed approach.