Voltage-Balancing Strategy for Three-Level Neutral Point Clamped Cascade Converter under Sequence Pulse Modulation

Loss Balancing in Three-level Active-neutral-point-clamped Converter

The 3L-NPC (Neutral-Point-Clamped) is the most popular multilevel converter used in high-power medium-voltage applications. An important disadvantage of this structure is the unequal distribution of losses among the switches. The performances of 3L-NPC structure were improved by developing the 3L-ANPC (Active-NPC) converter which has more degrees of freedom. In this paper the switching states a...

Modified Unipolar Carrier-Based PWM Strategy for Three-Level Neutral-Point-Clamped Voltage Source Inverters

This paper presents a simple modified unipolar carrier-based pulsewidth modulation (CBPWM) strategy for the three-level neutral-point-clamped (NPC) voltage source inverter (VSI). Analytical expressions for the relationship between modulation reference signals and output voltages are derived. The proposed modulation technique for the three-level NPC VSI includes the maximum and minimum of the th...

Smooth Switching Technique for Voltage Balance Management Based on Three-Level Neutral Point Clamped Cascaded Rectifier

Abstract: This paper discussed the topology of in the three-level neutral point clamped cascaded rectifier (3LNPC-CR) for designing the Chinese Power Electronic Traction Transformer (PETT). To balance the DC-link voltage (Vdc) in 3LNPC-CR, a smooth switching technique is proposed in this paper. The controlling processes of each module are relatively independent when the proposed technique is ap...

Diode Free T-type Three-level Neutral Point Clamped Inverter for Low Voltage Systems

A Study of Three-Level Neutral Point Clamped Inverter Topology

The three-level Neutral Point Clamped (NPC) inverter has become matured and widely used topology in high-power medium-voltage applications due to several advantages associated with it as compared to other available multilevel topologies. This paper presents a brief review on operation of threelevel NPC inverter. Different modulation strategies used in NPC inverter is also discussed. The problem...