DC link capacity enhancement for dynamic operation of back-to-back modular multilevel converters

With the increasing appearance of DC loads and DC sources in the MVAC distribution grids, the need for DC power systems is getting more and more pronounced. As a result, the MMC has become a promising and innovative technology that can serve as the interface between a DC and AC network. The MMC-based MVDC distribution link is one of the...

Supplementary control based on current source coupling for improving dynamic characteristics of active distribution network

Supplementary control (SC) technology is widely leveraged by power supply companies in active distribution networks (ADNs) to improve their stability and dynamic characteristics. Yet, the existed SCs are generally implemented from inside the converter controllers of distributed generators (DGs) or active loads, so there is a need to redesign...

Microinverter for Residential PV Systems

Up to 5 kW PV installations microinverters are common alternatives for the typical string solar inverters. The main draw back of the technology is the slight higher initial cost, however, a more efficient energy generation can be achieved if one of the PV modules are operated optimally at the maximum power point. This work shows that converters...

A Power Hardware-in-the-Loop Based Method for FAPR Compliance Testing of the Wind Turbine Converters Control

A task for new power generation technologies, interfaced to the electrical grid by power electronic converters, is to stiffen the rate of change of frequency (RoCoF) at the initial few milliseconds (ms) after any variation of active power balance. This task is defined in this article as fast active power regulation (FAPR), a generic definition...

Voltage Source Converter Control under Distorted Grid Voltage for Hybrid AC-DC Distribution Links

Back-To-Back (B2B) Voltage Source Converter (VSC) with AC-side LCL filters can be adopted for parallel AC-DC distribution links. In this paper, Grid-side Current Control (GCC) for the inner/fast control loops of the front- and backend power electronics are implemented in order to enhance the system performance against grid disturbances. Herein,...

A Solid-State Transformer for Interconnection between the Medium- and the Low-Voltage Grid

In recent years the complexity of the grid systems has grown due to the increased penetration of renewable energy and distributed generation sources. The increased complexity requires new methods to quickly manage the changing sources and loads. This research focuses on one of such technologies, called the Solid State Transformer (SST). A SST...