H‐Infinity versus model predictive control methods for seamless transition between islanded‐ and grid‐connected modes of microgrids

Abstract

This study presents two proposed adaptive and intelligent control schemes for accurately adjusting the MG voltage and frequency in islanded mode and ensuring the seamless transition between islanded and grid-connected modes. The two proposed controllers are based on improving the performance of the droop control method depending on H-infinity and model predictive control methods. However, when the MG connected to the utility grid, the MG is related to the grid voltage and frequency and the active and reactive power transfer is adjusted using the P/Q control method. Firstly, this study presents a comprehensive review of the commonly used control schemes in MGs. Then, the structure of the two proposed controllers is described and the Simulink model is presented. The controller is applied to an MG test system to validate its capability to meet requirements. In addition, a comparison between the two proposed controllers is made based on the integral of square error (ISE), integral of absolute error (IAE), and integral time-weighted absolute error (ITAE). The results prove that the two proposed control schemes have the ability to adjust the MG in its two operating modes and also provide a seamless transfer between the islanded and grid-connected modes of MGs. * λ weighting of the control action

Robust optimal utilization with a grid‐connected microgrid using EFO‐GBDT based controller technique with integrated converters

“…The three types of case studies utilized in this simulation section is, (a) under constant wind speed, the irradiance of PV is changed, (b) under constant irradiance of PV, the wind speed is varied, (c) under constant irradiance of PV and wind speed, the load fault is occurred. [33][34][35] The detailed delineation of these three cases is depicted in the section underneath using the graphical representation. Overall System Configuration of the EFO-GBDT model is shown in Figure 5.…”

To study unplanned islanding transient response of microgrid by implementing MSOG and SRF‐PLL based hierarchical control in the presence of non‐linear loads

“…7 represents the block diagram of selective virtual impedance by MSOGI frequencylocked loop (MSOGI-FLL) in the αβ frame. Equations (15) and (16) are shown the implemented selective virtual impedances, respectively,…”

“…Most literatures have studied about smooth transition in [8][9][10][11][12][13][14][15][16][17][18], but the effect of the presence of non-linear loads is not considered in these studies, simultaneously. In these researches, main grid and DGs in an MG are usually under balanced conditions and without any harmonic distortion.…”

“…In IM, voltage MPC and droop control are implemented as primary and secondary controls, respectively. The authors in [16] proposed an intelligent‐based control to adjust the MG in operating modes and provide a seamless transmission between them. In addition, an improved droop controller based on the two proposed controllers H‐infinity (HI) and MPC methods is implemented to control the voltage and frequency of MG in IM.…”

Guest Editorial: Challenges in Future Grid‐Interactive Power Converters: ControlStrategies, Optimal Operation, and Corrective Actions

“…Paper [17] presents a dual mode transition control for grid-connected microgrids by support of ESS and PV existing in microgrids to facilitate continuous operation at islanding condition. Similarly, paper [18] presents a model of a predictive control method to realise seamless transition between the islanded and grid-connected microgrids. Paper [19] proposes dual-stage cascaded control to resynchronize an isolated microgrid with the utility.…”