An Active-Neutral-Point-Clamped Switched-Capacitor Multilevel Inverter with Quasi-Resonant Capacitor Charging
- Publisher:
- IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
- Publication Type:
- Journal Article
- Citation:
- IEEE Transactions on Power Electronics, 2022, 37, (12), pp. 14888-14901
- Issue Date:
- 2022-01-01
Closed Access
Filename | Description | Size | |||
---|---|---|---|---|---|
An Active-Neutral-Point-Clamped Switched-Capacitor Multilevel Inverter with Quasi-Resonant Capacitor Charging.pdf | Published version | 10.76 MB |
Copyright Clearance Process
- Recently Added
- In Progress
- Closed Access
This item is closed access and not available.
Switched-capacitor (SC) multilevel inverters (MLIs) offer various advantages over conventional series MLIs owing to the operation from a single DC source, self-balanced capacitor voltages, and inherent voltage gain. However, these advantages come at the cost of high current stress on the capacitors, associated semiconductors, and the DC source. This inrush current has limited the practical application of SC-MLIs to a fractional kilowatt rating. This paper proposes a practical solution by introducing a unity gain 9-level active-neutral-point-clamped SC-MLI with an alleviated capacitor charging current. Switching loss in the SC circuit semiconductors is reduced by using a modified switching sequence that allows the charging current to flow with a minimum interruption till it is turned off at zero-current crossing. The structure also integrates protection against the detrimental effects of voltage transients across the charging inductor. The inverter exhibits a maximum efficiency of 98.03% at 583.91 W output power. Compared with similar SC-MLIs with hard-charging, the proposed inverter significantly reduces the losses and improves efficiency. Experimental results from a 2 kVA laboratory prototype validate the theoretical analysis and show the capacitor voltages stable under varying load impedance and modulation index.
Please use this identifier to cite or link to this item: