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This paper formulates a maximum power point tracking (MPPT) technique that accurately tracks the maximum power point of photovoltaic (PV), which undergoes simultaneous or independent sudden changes in load resistance and irradiance. The proposed algorithm is fundamentally divided into three parts; current and voltage perturbation algorithm (IPA/VPA), perturbation step-size reduction algorithm (PSSRA) and a deviation avoidance loop. The use of dual perturbation parameters using IPA and VPA ensures high tracking speed. PSSRA iteratively reduces the perturbation step-size of IPA and VPA and helps in reducing the power oscillations around MPP. Finally, a deviation avoidance loop is developed to detect a change in irradiance by examining the sign of the slope of the two power curves, namely P-V and P-I. The algorithm compares the per unit change in voltage and current of PV, to determine a simultaneous change in both irradiance and load resistance. The proposed algorithm is compared with two recently developed MPPT algorithms. The results show that the proposed technique can track the MPP with high speed and low steady-state oscillations and does not deviate from the MPP tracking path regardless of fast changes in irradiance and load resistance.

High penetration of PVs within the grid system has initiated policies and regulations to enable and encourage selfconsumption PVs as a viable solution for mitigating adverse effects of high pv-penetration on grid as also for reducing energy cost to the prosumer. This solution comes with an additional cost of energy storage such as battery. This paper presents an economic assessment of grid-connected PV systems for self-consumption. Assuming values for performance ratio of PV system, insolation level, inflation, interest rates and incentive grants, the levelized cost of electricity (LCOE) is evaluated for the case study in Malta. The influence for incentives proposed by the Maltese Government is analysed.

This paper aims to highlight the endeavors of a microgrid campus development from data to design stage that is under development at the Malta College of Arts, Science and Technology (MCAST), Malta. Malta is an island in the middle of the Mediterranean Sea having an area of 316km2 and receives the highest EU solar irradiance. The MCAST micro-grid is the first living laboratory for training and research on the island with onethird of the campus fully development in state-of-the-art facilities. In this case study, the loads consumption, photovoltaic (PV) generation and potential Electric Vehicles (EVs), that may support the campus when necessary are analysed for further designs supported by over 2 years of campus data. This analysis would provide the understanding of integrating future EVs on campus and higher penetration of PVs while keeping high consumption loads at watch. In addition, reliability and cost factors of the MCAST micro-grid are considered and recommendations are given on the infrastructure to complete campus wide transformation.

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As the number of distributed generation power plants are being increasingly connected to the grid, the system operators are continuously revising the grid codes which enhance the reliability for a continuous supply of power. The power electronics interface plays a vital role in controlling the amount and quality of power components that are injected into the grid. Thus, a well-designed current control strategy is essential which governs the performance of the grid-connected PV (GCPV) system under normal or fault conditions. The selection of appropriate control strategies also helps in fulfilling various control objectives. This paper evaluates the performance of conventional current control techniques of GCPV systems, when subjected to sudden variation in irradiance under unbalanced grid faults. The MATLAB/Simulink results helped in comparing the peak current amplitude in faulty phase of these four conventional strategies. Finally, the THD of these control strategies are compared to determine their overall performance.

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Widespread Photovoltaics (PVs), which are seen by a distribution network (or an isolated microgrid) as a constant power injecting source, can be detrimental to the frequency stability of the network. To assist in frequency regulation and response, the constant current control for a Distributed Energy Resource is substantially modified to provide inertial response within the low voltage network. PVs that deploy inertial control require an additional storage in order to cater to the demand supply balance. This approach is feasible for large scale PVs, however, rooftop PVs possess limited flexibility for additional storage. This paper studies case of a low-voltage networked microgrid with an appreciable PV penetration, in the presence of a diesel generator (DG) as a separate bus. A coordinated control for PV is designed in this paper, which can help in the transition in between the grid-forming mode to the grid-following modes (with the inertial control loop acting as the Phase locked loop), with the help of an auxiliary DC link voltage based control which is designed in a way that does not require any switching action.