Next Article in Journal
Co-Simulation of Smart Distribution Network Fault Management and Reconfiguration with LTE Communication
Previous Article in Journal
Visualization of Operational Performance of Grid-Connected PV Systems in Selected European Countries
Open AccessArticle

Research on the Neutral-Point Voltage Balance for NPC Three-Level Inverters under Non-Ideal Grid Conditions

1
Nanjing University of Science and Technology, Nanjing 210094, China
2
Jiangsu Collaborative Innovation Center for Smart Distribution Network, Nanjing 211167, China
*
Author to whom correspondence should be addressed.
Energies 2018, 11(6), 1331; https://doi.org/10.3390/en11061331
Received: 8 April 2018 / Revised: 15 May 2018 / Accepted: 19 May 2018 / Published: 23 May 2018
(This article belongs to the Section Electrical Power and Energy System)
In order to solve the neutral-point voltage unbalancing problem for neutral-point clamped (NPC) three-level inverters under non-ideal grid conditions, a novel zero-sequence component injection method for modulation signals was proposed in this paper. Based on the mathematical expressions of neutral-point voltage unbalancing, the fluctuation of the neutral-point voltage under different grid conditions was studied. The proposed method dynamically calculates the zero-sequence component for modulation signals by region selections based on sinusoidal pulse width modulation (DCR-SPWM). Under non-ideal grid conditions, this DCR-SPWM method can control the neutral-point voltage balance for NPC three-level inverters with different grid and output power conditions, and improves the grid current quality. The simulation results verified the correctness of the theoretical analysis in this paper, and the feasibility and effectiveness of this method were verified by the experiments in the experimental platform of the NPC three-level grid-connected inverter based on DSP-CPLD controllers. View Full-Text
Keywords: non-ideal grid; three-level inverters; neutral-point voltage balance; modulation signals; region selection non-ideal grid; three-level inverters; neutral-point voltage balance; modulation signals; region selection
Show Figures

Figure 1

MDPI and ACS Style

Lyu, J.G.; Wang, J.D.; Hu, W.B.; Wu, Z.F. Research on the Neutral-Point Voltage Balance for NPC Three-Level Inverters under Non-Ideal Grid Conditions. Energies 2018, 11, 1331.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop