Smooth DC-Link Y-Source Inverters: Suppression of Shoot-Through Current and Avoiding DC Magnetism

The Y-source impedance network is truly referred to as the origin of the magnetically coupled impedance source inverters. The key characteristics, including high boost capability and design flexibility, are associated with the coupled inductor turn ratio. However, the magnetic element brings some practical challenges, such as voltage spikes, high shoot-through (ST) current, and bulky coupled inductors. This article proposes two new Y-source inverters with clamped dc-link voltage. Due to the high boost ability, they are suitable for single-stage high gain inversions. Additionally, the significant reduction in the amplitude of the ST current leads to a reduction of the total power loss and capacity of the reactive component. Another attractive characteristic is that the Y-shaped coupled inductor's stored energy is no longer affected by the power rating of the converter, as a result of the zero dc magnetizing current. All these contribute to the high efficiency and power density of the proposed converters. The design guidelines of the components are presented and a thorough comparison with the state of the art is carried out. The achievements are then confirmed through extensive tests on a 500 W laboratory setup.

Automated summary

This article introduces two new Y-source inverters with clamped dc-link voltage, which have high boost capability and design flexibility, can reduce the amplitude of shoot-through current, and improve power density and efficiency.