As the electronic interfaces between distributed energy resources and the electrical network, power converters play a vital role in voltage stabilization and power conversion. So far, various power converter control methods have been developed. Now it is urgently needed to compare and understand these approaches to support the smart microgrid pyramid. This article provides an overview of the state-of-the-art of parallel power converter control in microgrid applications. The most important control schemes to address existing challenges, including concentrated control, master–slave control, droop mechanism, virtual synchronous generators, virtual oscillator control, distributed cooperative control, and model predictive control, are highlighted and analyzed in detail. In addition, the hierarchical control structure, as well as future trends, are reviewed and discussed.

Overview of Power Converter Control in Microgrids—Challenges, Advances, and Future Trends

As the electronic interfaces between distributed energy resources and the electrical network, power converters play a vital role in voltage stabilization and power conversion. So far, various power converter control methods have been developed. Now it is urgently needed to compare and understand these approaches to support the smart microgrid pyramid. This article provides an overview of the state-of-the-art of parallel power converter control in microgrid applications. The most important control schemes to address existing challenges, including concentrated control, master–slave control, droop mechanism, virtual synchronous generators, virtual oscillator control, distributed cooperative control, and model predictive control, are highlighted and analyzed in detail. In addition, the hierarchical control structure, as well as future trends, are reviewed and discussed. 

As the use of distributed generation with power electronics-based interfaces increases, the separation between DC and AC parts of the grid is reduced. In such inverter-dominated AC grids, impedance-based analysis methods are proving to be more powerful than traditional state-space-based analysis methods. Even the conventional parameters and standards used to estimate the stability of generators and stronger grids cannot fully capture the dynamics of weaker, inverter-dominated grids. It then stands to reason that system impedances that are commonly used to analyze DC systems will be useful in the analysis of grid-forming inverters in these hybrid systems. To understand the value of studying the impedances of inverters and other elements in weak AC grids, this article reviews and describes the various ways in which impedance-based analyses can be used to define, assess, and improve the performance of grid-forming inverter controllers. An exemplary case using the conventional P-f/Q-V droop control demonstrates the application of impedance-based analyses to determine the impact of the controller on the input and output stability of the inverter.

https://www.mdpi.com/1996-1073/14/9/2686/pdf

Review of Impedance-Based Analysis Methods Applied to Grid-Forming Inverters in Inverter-Dominated Grids

This work has been supported by FCT—Fundacao para a Ciencia e Tecnologia within
the R&D Units Project Scope: UIDB/00319/2020. This work has been supported by the FCT
Project newERA4GRIDs PTDC/EEI-EEE/30283/2017, and by the FCT Project DAIPESEV PTDC/EEIEEE/30382/2017.

/pdf/review-of-a-disruptive-vision-of-future-power-grids-a-new-12ivl0e4ue.pdf

Review of a disruptive vision of future power grids: a new path based on hybrid AC/DC grids and solid-state transformers

As the use of photovoltaics becomes more widespread, new technologies for more efficient energy generation, transmission, and distribution based on power electronics converters are being developed. The most common applications are grid-on, energy storage, hybrid, and high voltage gain applications. These applications impose several additional requirements in the design of power converters associated with the solar battery’s maximum power tracking and operation in a wide range of input currents and voltages. The practical realization of such solutions can be implemented on the basis of various topologies, which requires a preliminary application of criteria for assessing their effectiveness. The paper conducts a comparison of different topologies on power converters based on two parameters that describe their cost and power loss for various PV applications. For a straightforward study, these parameters are represented using the gain factor, which allows for an accurate comparison of the efficiency of various types of converters.

/pdf/power-converter-solutions-for-industrial-pv-applications-a-2ls7ydgi.pdf

Power Converter Solutions for Industrial PV Applications—A Review

Owing to the smart lifestyle, environmental consciousness, and dwindling fossil fuel supplies, there is a huge demand for clean and green energy. Microgrid (MG) is a crucial approach to renewable and clean energy. Because of the success of the AC utility grid and the growing demand for critical loads, it is very convenient to provide AC/DC MG that can easily satisfy both the alternating current (AC) MG and the direct current (DC) MG requirements. Due to uncertainty in load variations, main grid failures, intermittent power generations from renewable energy sources (RESs), the synchronization and interconnection of different power converters are the paramount issues in the control of AC/DC MG. This article presents an overview-oriented state of the art in the recent advancement in control strategies of AC/DC MG and its associated power converters control. Based on recent research, this article summarizes unobstructed views on different topologies, types of power converters, power converter controls, and control strategies of AC/DC MG. Finally, it identified some future challenges that need to be addressed in order to develop a sustainable and reliable control strategy for AC/DC MG. This article will serve as a guide for researchers.

/pdf/a-comprehensive-review-on-power-converters-control-and-3167efbs0k.pdf

A Comprehensive Review on Power Converters Control and Control Strategies of AC/DC Microgrid

This paper presents a comprehensive analysis of direct and indirect matrix converter fed asynchronous motor drives. The algorithm of space vector modulation scheme is used for controlling the asynchronous motor drive. A separate simulation model for direct matrix converter fed asynchronous motor and indirect matrix converter fed asynchronous motor is presented and their performances are analysed. The result shows that indirect matrix converter fed asynchronous motor drive have improved steady state response with smoother torque characteristics.

Simulation based comprehensive analysis of direct and indirect matrix converter fed asynchronous motor drive

Operation and control of a synch invulnerable master‐slave organised islanded alternating current microgrid

Recently the tremendous advancement has been seen in the field of matrix converter topology. For high power drive applications, industries often need high power AC-AC converters like three level matrix converter because it is having the ability to generate a set of balanced sine waves for inputs as well as outputs. The three level matrix converters possess better output performance with reduced harmonic contents compared to all two-stage indirect matrix converters. In this matrix converter topology, the idea of neutral-point clamped-VSI is employed to the inversion step of the matrix converter circuitry. To control the power switches the gate signals are produced using NTVV based space vector modulation. To justify the theoretical study a complete model of a three-level twin-step matrix converter has been designed in Matlab/Simulink and its performances are analysed.  

/pdf/modelling-and-analysis-of-a-ntvv-svm-based-three-level-twin-2c00m40zih.pdf

Shamsher Ansari

Papers

A Comprehensive Review on Power Converters Control and Control Strategies of AC/DC Microgrid

Simulation based comprehensive analysis of direct and indirect matrix converter fed asynchronous motor drive

Operation and control of a synch invulnerable master‐slave organised islanded alternating current microgrid

Modelling and analysis of a NTVV-SVM based three-level twin-step matrix converter

Seamless plug-in plug-out enabled fully distributed peer-to-peer control of prosumer-based islanded AC microgrid