As a single-stage buck-boost inverter, the impedance-source inverter can achieve the step-up operation using the shoot-through states, which are not allowed in the conventional voltage source inverter (VSI). The introduction of the shoot-through state leads to a pulsating dc-link voltage, and the peak dc-link voltage is related to the shoot-through duty ratio. A small variation of the shoot-through duty ratio may result in significant changes in the boost gain. This means that the design of the impedance-source inverter require more attentions than the conventional inverter, especially for renewable energy sources like PV systems. The peak dc-link voltage can be controlled by directly measuring the dc-link voltage with additional sensors or indirectly through the capacitor voltage in the impedance-source network. However, the additional circuits increase the cost, and the indirect control of the capacitor voltage leads to higher requirements for the voltage withstanding capability of the inverter. In this paper, design considerations and limitations of the impedance-source inverters are then analyzed. The quasi-Z-source inverter is adopted as an example to demonstrate the analysis.
|Titel||Proceedings of 2019 IEEE 10th International Symposium on Power Electronics for Distributed Generation Systems (PEDG)|
|Status||Udgivet - jun. 2019|
|Begivenhed||10th International Symposium on Power Electronics for Distributed Generation Systems - Xi'an, Kina|
Varighed: 3 jun. 2019 → 6 jun. 2019
|Konference||10th International Symposium on Power Electronics for Distributed Generation Systems|
|Periode||03/06/2019 → 06/06/2019|
Liu, W., Yang, Y., & Kerekes, T. (2019). Characteristic Analysis of the Grid-Connected Impedance-Source Inverter for PV Applications. I Proceedings of 2019 IEEE 10th International Symposium on Power Electronics for Distributed Generation Systems (PEDG) (s. 874-880).  IEEE Press. https://doi.org/10.1109/PEDG.2019.8807487