Control of distributed generators and direct harmonic voltage controlled active power filter for accurate current sharing and power quality improvement in islanded microgrid

Harmonics are regarded as one of the main challenges in a microgrid. This issue may even get worse when different distributed generators (DGs) work together to solve the load sharing problems due to mismatched feeder impedances and diversified DG ratings. Even though load sharing can be achieved, the microgrid suffers from voltage unbalance and total harmonic distortion (THD) issues at the output of DG terminals as well as at the point of common coupling (PCC). Thus, in this paper, the power quality improving method is discussed, with a target of load sharing under the hierarchical control of different DG units and an active power filter (APF) in microgrids. To achieve this objective, we propose integrating a direct harmonic voltage controlled APF with DGs to improve their harmonic compensation performance. This proposed control scheme has many advantages over conventional control using a shunt resistive active power filter (R-APF) with voltage controlled DGs. First, based on the existing THD level of the PCC voltage, the proposed scheme provides improved voltage compensation and reduction in THD in the islanded microgrid. Secondly, equal load sharing can be achieved simultaneously. Thus, the proposed scheme provides better performance and a seamless interface as the proposed study mainly contains both the voltage controlled DGs and the local based voltage detection APF

Improving Convergence Speed of Bat Algorithm Using Multiple Pulse Emissions along Multiple Directions

Metaheuristic algorithms are effectively used in searching some optical solution space. for optical solution. It is basically the type of local search generalization that can provide useful solutions for issues related to optimization. Several benefits are associated with this type of algorithms due to that such algorithms can be better to solve many issues in an effective way. To provide fast and accurate solutions to huge range of complex issues is one main benefit metaheuristic algorithms. Some metaheuristic algorithms are effectively used to classify the problems and BAT Algorithm (BA) is one of them is more popular in use to sort out issues related to optimization of theoretical and realistic. Sometimes BA fails to find global optima and gets stuck in local optima because of the absence of investigation and manipulation. We have improved the BA to boost its local searching ability and diminish the premature problem. An improved equation of search with more necessary information through the search is set for the generation of the solution. Test set of benchmark functions are utilized to verify the proposed method’s performance. The results of simulation showed that proposed methods are best optimal solution as compare to others

Hybrid energy sources status of Pakistan: An optimal technical proposal to solve the power crises issues

Power outage owing to shortage of power generation, transmission losses, lack of planning and inappropriate policies has led to escalate the energy crisis in Pakistan. The reason for selecting Pakistan is to facilitate its 220 million population and to attract the international investors to take benefit by integrating power generation units into National Grid of Pakistan (NGOP). Domestic, Industrial, health and education sectors are badly affected due to this power crisis. Instead of remedial measures and providing incentives to the investors in power sector, the government of Pakistan (GOP) has remained unable to overcome the dilemma in power sector due to improper check and balance. The failures in completion of hydropower dams and generating electricity by fossil fuels has resulted in increased power generation cost and environmental hazards. Therefore, some suitable solutions are compulsory for meeting the escalating power demands adequately. The incorporation of renewable energy units and stopping electricity theft can be the most explicit choice for meeting aforementioned problems. This paper explores the vast potential of Pakistan with respect to energy production by means of solar and wind power units. Moreover, most appropriate sites for incorporating power generation units are also critically reviewed. The paper also proposes the short-term, mid-term and long-term effective solutions along various practical proposals for overcoming the existing power crisis in Pakistan. Keywords: Power outage, HVDC, Energy crisis, Energy solutions, Renewable energy, Pakista