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The management of energy in distribution networks has been gathering attention in recent years. The simultaneous control of generation and demand is crucial for achieving energy savings and can further lower energy pricing. The work aims to develop a control scheme for a hybrid microgrid that can provide stability to the bus voltage and effectively manage the power flow. Solar energy is the current trend in renewable energy sources (RES). There is a surge in the installation of solar PV systems both on a large scale and on a small scale, such as rooftop PV systems. Installation of RES at residential premises has to be conducted with a proper power management scheme. The hybrid microgrid for this work consists of a PV system with a boost converter to extract maximum power, a DC-DC bi-directional converter to charge or discharge the hybrid energy-storing devices, and a three-phase AC-DC interlinking converter for exchange of energy with the utility grid. The control and power management scheme checks the voltage of each unit and maintains the power flow according to operating conditions. Disturbances are introduced in the form of load switching and irradiance variation to check the system performance. The system is tested on the MATLAB (R2021a) Simulink platform for varying its different modes of operations. An experimental set-up has been developed with hardware-in-the-loop to validate the simulation results. [ABSTRACT FROM AUTHOR]

Increasing awareness for green energy and sustainable energy management has accelerated the popularity for the incorporation of distributed energy resources and distributed energy storage into the distribution network and microgrid. This has proliferated the use of power electronic-based devices giving rise to a serious issue of deteriorating power quality (PQ) in the distribution system. In this context, this article presents a photovoltaic (PV) integrated unified power quality conditioner (UPQC) operating with an adaptive compensating technique based on variable leaky least mean square (VLLMS) algorithm. It is a soft computing-oriented method that offers quicker convergence to the desired condition in an iterative approach keeping the weight of the updating parameters within the specified limit. The VLLMS-based algorithm eliminates the use of low pass or moving average filter for the extraction of fundamental components from polluted source voltage and load current to generate reference signal for the switching of shunt as well as series voltage source converters (VSC) of the UPQC. Due to the involvement of feed-forward component of PV in the compensating technique of shunt VSC, it efficiently and smoothly manages power balance between grid, load, and PV besides resolving the PQ issues of current harmonics and poor power factor at PCC. It also ensures the regulation of dc-link voltage. The series converter maintains pure sinusoidal voltage at the load terminal irrespective of sag/swell and harmonics present in the grid voltage. The effectiveness of the proposed system is verified through simulation as well as hardware implementation under different static and dynamic operating conditions. [ABSTRACT FROM AUTHOR]

This article shows the motivation towards the development of a novel hybrid fuzzy‐based sliding mode control scheme for photovoltaic tied DSTATCOM topology for eliminations of perturbations in source currents and reactive power compensation. A LCLC type passive filter is employed at the output of PV fed DSTATCOM, which helps to connect the solar system to a grid. The presence of the series capacitor in the passive filters decreases dc link voltage, which helps in reducing the ratings of DSTATCOM in the proposed system. The switching signals for the PV fed DSTATCOM is generated by the utilization of novel hybrid fuzzy‐based sliding mode control scheme. To improve the efficiency of dc link voltage controller and to regulate the dc link voltage, fuzzy logic‐based approach has been utilized. The controller performance has been compared with conventional algorithms of reference signal generation to analyze the efficiency. An experimental prototype has been developed in the laboratory and results are analyzed to validate the efficiency of the proposed controller. [ABSTRACT FROM AUTHOR]

Summary: In this paper, a novel photovoltaic‐tied unified power quality conditioner (PV‐tied UPQC) scheme is proposed for elimination of major current‐ and voltage‐related power quality issues present in the distribution system. Photovoltaic‐tied UPQC topology is completely new in its category of photovoltaic grid integration. Although advanced UPQC schemes have been discussed in literatures, but concepts related to PV‐tied UPQC are few in number to discuss elaborately about elimination of power quality issues. In this paper, a new PV‐tied UPQC topology with an improved LCL filter at shunt inverter part is proposed, which provides better compensation to current quality issues. This paper also proposes a novel model reference tracker control law to improve power quality and elimination of current harmonics, voltage sag/swells, and unbalance. It has feature to regulate tracking error between model reference signal and actual measured signal. Therefore, proposed model reference approach provides robustness and flexibility for various operating conditions. In addition, integral plus sliding mode controller has been used for better control of dc‐link voltage to deal with severe change in power system conditions. Performance and efficiency of present topology with novel controller is analyzed along with conventional controllers through laboratory developed prototype, controlled by DS1103 dsp processor. [ABSTRACT FROM AUTHOR]

This paper deals with grid integration of photovoltaic systems through single-phase unified power quality conditioner (PV-1UPQC) based on notch filter novel control algorithm for its function such as better phase detection, voltage sag/swell, voltage unbalance, voltage and current harmonics eliminations. A notch filter-based control algorithm includes a phase-locked loop (PLL) mechanism which is responsible to avoid multiple zero crossing at the time of highly distorted grid voltage detection. Notch filter PLL-based control algorithm is applied to both series and shunt inverters of PV-tied UPQC. In addition to normalizing voltage and current perturbations, proposed controller has feature of phase detection and perfect grid synchronization. Synchronous reference d-q frame controller and unit vector control algorithm with conventional PLL is also studied, utilized and evaluated for control of PV-1UPQC. Hardware setup is developed in laboratory using DS1103 dSPACE processor. Performance and efficiency of PV-1UPQC are analyzed through simulation and experimentation for various operating conditions. [ABSTRACT FROM AUTHOR]

This paper proposes a new hybrid maximum power point tracking (MPPT) algorithm combining grey wolf optimization (GWO) and perturb & observe (P&O) technique for efficient extraction of maximum power from a photovoltaic system subjected to rapid variation of solar irradiance and partial shading conditions. GWO handles the initial stages of MPPT followed by application of the P&O algorithm at the final stage in view of achieving faster convergence to the global peak (GP). This MPPT thus overcomes the computational overhead as encountered in the case of a GWO-based MPPT algorithm reported earlier by Mohanty et al. The idea behind using the hybrid technique is to scale down the search space of GWO which helps to speed up for achieving convergence toward the GP. The proposed MPPT algorithm is first implemented using MATLAB/Simulink and subsequently an experimental setup is prepared for its practical implementation. From the obtained results, it is confirmed that the proposed MPPT provides superior tracking performance in any weather conditions compared to both GWO and PSO+PO-based MPPT algorithms. [ABSTRACT FROM AUTHOR]

This paper presents a single-phase grid-connected photovoltaic power system with the capability of maximum power point tracking (MPPT) of photovoltaic (PV) array and reactive power compensation. The non linear characteristics of the proposed modified p-q theory have been improved with the help of maximum power point tracking (MPPT) controller. MPPT controller helps to feed the inverter with maximum power from the solar grid, for switching pattern generation hysteresis controller is used. The simulation results developed in MATLAB/Simulink software, verify the performance and advantages of the proposed system used to integrate the single phase grid to photovoltaic for enhancing the power quality. Also the proposed scheme has been verified in laboratory setup for its real time implementation. [ABSTRACT FROM AUTHOR]

This paper proposes a low rating photovoltaic fed improved hybrid distributed static compensator (DSTATCOM) for the compensation of harmonics and reactive power. The proposed system satisfies the load active power demand with reduced power rating of the photovoltaic source for same load rating as compared to the standard L or LCL filters. The system is modeled and controlled by considering the non-linearity of the system. A dc voltage droop regulator is used to control the power flow from solar system and to maintain dc link voltage. To make the system robust, switching pulses for inverter is generated using sliding mode controller. The efficacy of proposed model with sliding mode controller over linearly controlled system is validated through simulation results. The proposed system prototype is developed and operated in real time to show the effectiveness of the system. [ABSTRACT FROM AUTHOR]

This paper presents a comparative assessment of two controllers, namely sliding mode controller and hysteresis controller for active power filtering of a grid integrated Photovoltaic (PV) system. These control algorithms were employed in Voltage Source Inverter (VSI) for active power filtering as well as for converting the dc voltage from PV array to 3-phase ac voltage. For superior tracking efficiency a modified Incremental Conductance Maximum Power Point Tracking (ICMPPT) algorithm is employed to extract maximum power from PV panels. A PI controller is used for regulation of dc link capacitor voltage. Instantaneous power theory based reference current generation is used for the active power filtering. Both sliding mode control algorithm and hysteresis control algorithm are designed for tracking the reference inverter current in order to elimination the grid current harmonics. The steady state and transient performances of the two controllers i. e. sliding mode controller and hysteresis controller are compared. These two control schemes are implemented on a grid connected PV system firstly using MATLAB/Simulink and then on an experimental setup developed in the laboratory. From the obtained simulation and experimental results, it is found that sliding mode controller exhibits superior performance such as better transient and steady state behavior under parameter uncertainties as compared to the hysteresis controller. [ABSTRACT FROM AUTHOR]