<p class="Abstract">The conventional three-phase alternating current (AC) to direct (DC) converter can be modified using two isolated-gate bipolar transistor (IGBT) as by-pass switches connected tapping points on the secondary side of transformer. This scheme yields a reduction in both harmonic contents and reactive volt-ampere absorption. possibly eliminates need for an on-load tap-chang...

Multilevel inverters have been developed due to limitations of the conventional two-level voltage source inverters (VSIs). Most of the topologies of multilevel inverters that have been presented in the literature are based on the sharing of the rated voltage between the switches so that the switches with lower voltage ratings can be used. In these topologies, the current rating of all of the sw...

First of all, in this paper, the topology and operation of the three-phase three-level Z-source inverter based on neutral-point-clamped (Z-NPC) are studied. Moreover, different combinations of permissible switching states and control signals are explained for this inverter. In this paper, the topology of the three-phase three-level Z-NPC inverter is extended for an n-level state. Also, a combin...

In this paper, dynamic performance of a transformerless cascaded PWM static synchronous shunt compensator (STATCOM) based on a novel control scheme is investigated for bus voltage regulation in a 6.6kV distribution system. The transformerless STATCOM consists of a thirteen-level cascaded H-bridge inverter, in which each voltage source H-bridge inverter should be equipped with a floating and iso...

The cascaded three-level neutral-point-clamped (3L-NPC) converter and the modular multi-level (MMC) are attractive solutions for medium-voltage direct-current (MVDC) applications. Due to their low cost compared MMCs, 3L-NPC converters have been adopted in ANGLE-DCa 30 MVA MVDC link demonstration project North Wales, UK. DC voltage imbalance across submodules (SMs) is a common challenge both typ...