Enhancement of power quality issues for a hybrid AC/DC microgrid based on optimization methods

Abstract

The purpose of this paper is to study the harmonic behavior of hybrid microgrids (MGs). To achieve the desired goal, a modified active power filter (MAPF) and a power filter compensator kit (PFCK) modules have been used to improve the harmonics of the AC part of the system. The main challenge and feature of this research is the optimization of MAPF and PFCK controller gain coefficients hierarchical, using Harris hawk optimization (HHO), grasshopper optimization algorithm (GOA), artificial bee colony (ABC), and differential evolution (DE), respectively. Following, this technique was applied in the three control loops including, voltage and current harmonics, and system controller error to reduce the range of the mentioned harmonics to the permissible range. The method will be interesting considering that the PI and PID tuning is based on parallel feed‐forward. The programmed objective functions include the three components current THD, voltage THD and controller error hierarchically. From the point of view of the MGs hierarchical control, the method presented in this study will be implemented in the second level of hierarchical control. In order to improve the operation of the DC part of the grid, a boost converter module (BCM) has been introduced in the form of a new synchronization scheme. The output of the simulation shows the reduction of the harmonic amplitude of the system by the mentioned modules.

Event‐triggered distributed secondary control for enhancing efficiency, reliability and communication in island mode DC microgrids

“…The secondary control level comprises of both the voltage regulation loop and the current regulation loop [7]. The voltage regulation loop compensates for the voltage deviation caused by the droop control.…”

“…The current regulation loop adjusts the power distribution based on the fluctuating power generation of RES and the battery charge status. The correction voltage values obtained from both regulation loops are added together and transmitted to the primary control [7]. $$$$\begin{equation}\delta {v}_i = \delta {v}_{V,i} + \delta {v}_{I,i},\end{equation}$$$$where 𝛿𝑣 𝑉 ,i is the voltage regulation term and 𝛿𝑣 I,i is the current regulation term at node i .…”

Variable weight coefficient MPC control strategy for qZSI‐VSG wind power grid‐connected system

“…Some nonlinear control algorithms have been applied to the qZSI system, including neural network control, fuzzy control, and sliding mode control of the BHO and PSO methods to adjust PI-MR controller parameters. Compared to conventional linear control algorithms to reduce the system's harmonic perturbations [20][21][22][23][24]. In actual control, each controller is independent of each other, and the number of states and constraints need to be dynamically calculated as the working conditions change.…”

Unified power quality control based microgrid for power quality enhancement using various controlling techniques

“…Using the proposed design, UPQC gained active and reactive power injection capabilities in addition to its well-known benefit. Experiments were carried out in various circumstances to validate the efficacy of the suggested strategy in increasing power quality metrics [19], [20]. In series circuit is controlled by DVR, and the voltage varies in response to load variations, which are assessed using the suggested rational energy transformative optimization algorithm [21].…”