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        1 - Providing Improved Structure and Adaptive Control Strategy for Solar System with the Ability to Improve Power Quality in Islanded Microgrid
        Reza Ghobadi Ghazanfar Shahgholian
        Due to the ever-increasing price of fossil fuels and growing concerns about environmental pollution, the utilization of renewable resources, such as photovoltaic (PV) systems, has witnessed significant growth. However, the lack of an optimal structure and control strate More
        Due to the ever-increasing price of fossil fuels and growing concerns about environmental pollution, the utilization of renewable resources, such as photovoltaic (PV) systems, has witnessed significant growth. However, the lack of an optimal structure and control strategy for PV systems poses a crucial challenge in fully exploiting their potential capabilities. This article proposes a suitable structure and adaptive control strategy for PV systems, enabling the maximum utilization of PV system capabilities in island microgrids. The proposed control structure and strategy are based on a two-stage converter, facilitating maximum power point tracking in PV, injecting the generated PV power into the microgrid with minimal harmonic levels, and improving the power quality of the microgrid by compensating for harmonic components. In this method, the tasks of the DC/AC converter, including the injection of PV active power into the microgrid, provision of reactive power, and harmonic compensation, are prioritized and managed by considering the current peak limitation to prevent inverter overcurrent. Additionally, an adaptive controller is designed to enhance the accuracy and speed of power control. The proposed structure and strategy have been evaluated by simulating a sample microgrid in MATLAB/Simulink. The simulation results demonstrate that the proposed method enables the PV system to operate at maximum power with minimum harmonic levels, leading to a significant improvement in the speed and accuracy of the control system and enhancing the power quality of the islanded microgrid. Manuscript profile
      • Open Access Article

        2 - Improving Performance of Total Harmonic Distortion Based Fault Detection Scheme for Inverter Interfaced Islanded Microgrids
        Iman Sadeghkhani
        Global warming and environmental concerns have led to increasing penetration of converter interfaced renewable energy resources. One of the main challenges of inverter interfaced islanded microgrids is the fault detection. This paper investigates the performance of tota More
        Global warming and environmental concerns have led to increasing penetration of converter interfaced renewable energy resources. One of the main challenges of inverter interfaced islanded microgrids is the fault detection. This paper investigates the performance of total harmonic distortion (THD) based fault detection scheme when various inverter topologies, main current limiting strategies, and different reference frame are employed. Then, based on this analysis, the performance of THD based fault detection scheme is improved using the instantaneous saturation limit and independent control capability in the natural reference frame. The proposed scheme does not mal-operate in the presence of non-linear loads and can distinguish fault condition from load change. Also, using the auxiliary control system, the proposed fault detection scheme is capable of detecting single line to ground fault in three wire system when synchronous/stationary reference frame is employed. Various time-domain simulations verify the effectiveness of the proposed scheme in the case of symmetrical and unsymmetrical faults. Manuscript profile