Comprehensive review of trends in microgrid control

Sunflower optimization algorithm-based optimal PI control for enhancing the performance of an autonomous operation of a microgrid

The importance of microgrids has been acknowledged with the increasing amount of research in direct current (DC) microgrids. The main reason for this is the straightforward structure and efficient performance. In this research article, double integral sliding mode controllers (DISMCs) have been proposed for energy harvesting and DC microgrid management involving renewable sources and a hybrid energy storage system (HESS). DISMC offers a better dynamic response and reduced amount of chattering than the traditional sliding mode controllers. In the first stage, the state differential model for the grid was derived. Then, the nonlinear control laws were proposed for the PV system and hybrid energy storage system to achieve the main objective of voltage regulation at the DC link. In the later part, the system’s asymptotic stability was proven using Lyapunov stability criteria. Finally, an energy management algorithm was provided to ensure the DC microgrid’s smooth operation within the safe operating limit. The proposed system’s effectiveness was validated by implementing on MATLAB/Simulink software and comparing against sliding mode control and Lyapunov redesign. Moreover, to ensure the proposed controller’s practical viability for this scheme, it has been tested on real-time hardware-in-the-loop test bench.

https://www.mdpi.com/1996-1073/14/13/3988/pdf

Dynamical Operation Based Robust Nonlinear Control of DC Microgrid Considering Renewable Energy Integration

Integration of distributed energy resources (DER) has always posed a challenge. Smart inverters have started playing a crucial role in efficient integration of DERs. With the basic functionalities of traditional inverters in place, smart inverters can provide grids with related ancillary services either from the customer side or from the utility as well. The ancillary/augmented service from smart inverters includes the concept of reactive power exchange with the grid. Such grid support functions includes the functionalities of photovoltaic/plug in electric vehicles (PV/PEV) inverters as a static synchronous compensators (STATCOMs) by performing virtual detuning, temporary over voltage (TOV) mitigation, voltage regulation, frequency support and ride through capabilities. As the penetration levels of DERs have gone up, the need for such ancillary services has grown as well. This paper is organized in such a way that it will serve as a benchmark for smart inverter technologies in the form of a review. It includes several domains involving the applications, advanced and coordinated control, topologies and many more aspects that are associated with smart inverters based on reactive power compensation schemes for ancillary services. Apart from that, the applications those are associated with smart inverters in the smart grid domain are also highlighted in this paper.

Novel Exertion of Intelligent Static Compensator Based Smart Inverters for Ancillary Services in a Distribution Utility Network-Review

An iterative adaptive virtual impedance loop for reactive power sharing in islanded meshed microgrids

Islanding operation scheme for DC microgrid utilizing pseudo Droop control of photovoltaic system

DC-DC boost converters are necessary to extract power from solar panels. The output voltage from these panels is far lower than the utility voltage levels. One of the main functions of the boost converter is to provide a considerable step-up gain to interface the panel to the utility lines. There are several techniques used to boost the low panel voltage. Some of the issues faced by these topologies are a high duty ratio operation, complex design with multiple active switches and discontinuous input current that affects the power drawn from the panel. This paper presents a boost converter topology that combines the advantages of an interleaved structure, a voltage lift capacitor and a passive voltage multiplier network. A mathematical analysis of the proposed converter during its various modes of operation is presented. A 100 W prototype of the proposed converter is designed and tested. The prototype is controlled by a PIC16F18455 microcontroller. The converter is capable of achieving a gain of 10 without operating at extremely high duty ratios. The voltage stress of the switch is far lower than the maximum output voltage. 

/pdf/non-isolated-interleaved-hybrid-boost-converter-for-hb1ob9bz.pdf

Girish Ganesan Ramanathan

Papers

Islanding operation scheme for DC microgrid utilizing pseudo Droop control of photovoltaic system

Non-Isolated Interleaved Hybrid Boost Converter for Renewable Energy Applications