Abstract:
As a typical single-phase electric power system, high-speed railway system gradually absorbs the more single-phase electric traction vehicles (trains) with its rapid deve...Show MoreMetadata
Abstract:
As a typical single-phase electric power system, high-speed railway system gradually absorbs the more single-phase electric traction vehicles (trains) with its rapid development. Traction power load (TPL) is the electrical part of the train. The incompatible interactions between traction power network (TPN) and TPL generally cause the serious wideband oscillations, fortunately, which can be readily analyzed with the identified wideband impedances. As for impedance identification, the multi-frequency harmonic generator is of great significance to rapidly excite the desired responses for impedance calculation, however which is vacant for the single-phase TPL, and needs a further study. Aiming at it, this article proposes a multi-frequency harmonic generator based on the transformer-less cascaded H-bridge (CHB) converters with floating DC capacitors. In detail, its corresponding multi-frequency harmonic control loop is derived by the internal model principle (IMP), and the inserted notch filter and repetitive controller can strengthen the multi-frequency harmonic output performance. Finally, results of simulation and corresponding down-scale physical experiment can well verify that the proposed harmonic generator can output multiple harmonics simultaneously with high purity and well-behaved tracking performance.
Published in: IEEE Transactions on Vehicular Technology ( Volume: 72, Issue: 12, December 2023)