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The major shortcoming in the extraction of electrical energy occurs due to partial shading over a limited area of vast spread solar panels underpinning reduction of efficiency. A number of panels are interconnected in series and parallel to form a photovoltaic (PV) array for large power plants and a shadow over a single cell deteriorates overall performance. As a consequence, several peaks are added to the P-V curve causing hotspots in PV panels, degradation of the PV system, and collapse of tracking algorithms. In order to minimize such issues in PV panels, an effective optimization technique is developed by reconfiguring the panels which are capable of reaching the full global power point in a PV system under partial shading conditions. The study proposes particle swarm optimization (PSO) using PV characteristics of Quaid-e-Azam Solar Plant (QASP) in Punjab, Pakistan1. In PSO, electrical connections of PV modules are changed keeping their physical locations unaltered aiming to improve the performance of the PV system. After reconfiguration, the algorithm finds the best combination of PV modules by equalizing the row currents followed by the comparison of row current, voltages, and power of panels. The proposed PSO is proved to be an efficient method for reconfiguring PV modules in very less computational time by increasing the output power of shaded modules.

The protection of power system is an essential trait in a huge network to efficiently detect and isolate the sections undergoing faults or abnormal behaviour. The key components of a protection scheme include circuit breakers, relays, switchgears and fuses which employ communication from one station to another to achieve high-speed tripping. The automation of these components at the laboratory level using programmable logic controller (PLC) along with supervisory control and data acquisition (SCADA) system owns paramount importance for intelligent decision making, sensing, actuating, monitoring and maintaining the record in the host server. This paper discusses such a technique for conventional power system protection laboratory at a new level of development to promote a control system through PLC and SCADA. The control system has indication of over and under values of voltage, load and frequency, which can trigger malfunctioning of equipment and must be rectified. Furthermore, ground fault and inverse current indication are added to the system for monitoring and controlling purposes. The proposed system enhances the efficiency and safety of the expensive equipment and the personnel to the next level and also introduces new standards of automated protection schemes for modern technical institutes.

In an electrical power system, the ultimate aim is to generate and deliver electrical energy to consumer side with minimum cost involved. Thus, least fuel cost, effective unit commitment and minimum transmission losses are desirous to achieve economic dispatch in a distributed generation network. In this research, economic dispatch considering transmission losses in a distributed generation network of Bahawalpur is reported. A MATLAB algorithm is designed which gives optimum division of power between two power plants and their transmission losses. Power plants considered here are thermal power plant Muzafargarh and Kot Addu Power Company (KAPCO), the former being located at smaller distance from Bahawalpur district. Finally, load trend of Bahawalpur district, optimum generation verses power demand, associated transmission losses, penalty factor and fuel cost economy are shown in the Results Section through graphs and tables. It is concluded that thermal power plant shares higher contribution of load power due to smaller distance from load and, thus, smaller transmission losses ensuring minimum cost operation.

The impact of electric energy transfers from power plants generation to substations then to consumers and its own environment is tremendous. Among various hazards, the overhead wires associated with power lines are the most fatal hazard to birds. The power lines and poles have caused fatal risks for birds and have affected their habitats significantly. Dangerous types of power poles in the middle voltage lines which have small distances between the lines and short insulators cause short-circuits between conductor wires or ground-faults. This paper presents a survey conducted in Multan city, Pakistan. In this survey, all 132kV high voltage grids and their 11kV outgoing feeders are observed and their locations are also marked on Google map. This survey includes current construction type of power lines and poles, principles for bird safety, photographic records, public views about deadly poles and Ultraviolet vision in Birds. This study also highlights the cause of bird casualties on high and large scale from overhead power lines. It presents different technical solutions for bird safety such as proper adjustments to the routing of the power lines and power pole constructions can effectively reduce the risks posed to birds. Detailed study is recommended on large scale; so that conservation measures can be suggested for reduction of losses on birds by power stations in Pakistan. [ABSTRACT FROM AUTHOR]

Transmission line is a vital part of the power system that connects two major points, the generation, and the distribution. For an efficient design, stable control, and steady operation of the power system, adequate knowledge of the transmission line parameters resistance, inductance, capacitance, and conductance is of great importance. These parameters are essential for transmission network expansion planning in which a new parallel line is needed to be installed due to increased load demand or the overhead line is replaced with an underground cable. This paper presents a method to optimally estimate the parameters using the input-output quantities i.e., voltages, currents, and power factor of the transmission line. The equivalent π-network model is used and the terminal data i.e., sending-end and receiving-end quantities are assumed as available measured data. The parameter estimation problem is converted to an optimization problem by formulating an error-minimizing objective function. An improved particle swarm optimization (PSO) in terms of time-varying control parameters and chaos-based initialization is used to optimally estimate the line parameters. Two cases are considered for parameter estimation, the first case is when the line conductance is neglected and in the second case, the conductance is considered into account. The results obtained by the improved algorithm are compared with the standard version of the algorithm, firefly algorithm and artificial bee colony algorithm for 30 number of trials. It is concluded that the improved algorithm is tremendously sufficient in estimating the line parameters in both cases validated by low error values and statistical analysis, comparatively. [ABSTRACT FROM AUTHOR]

Dry band formation on the surface of outdoor insulators is one of the main reasons leading to flashover and power outages. In this paper, a dynamic arc model is proposed for single and multiple dry bands configuration to predict the critical flashover voltage for silicone rubber outdoor insulators. An arc is modelled as a time dependent impedance consisting of a Resistor Inductor Capacitor (RLC) circuit. The effect of dry band location and existence of multiple dry bands on critical flashover voltage is investigated. To validate the proposed model, experiments were conducted in a climate chamber under controlled environmental conditions on rectangular silicone rubber sheets polluted using improved solid layer method based on IEC 60,507. Tests were conducted at different dry band configurations and pollution severity levels. A good correlation was found between experimental results and simulation results. This model can provide a good foundation for the development of mathematical models for station post insulators having multiple dry and clean bands and can be used in the design and selection of outdoor insulators for polluted conditions. [ABSTRACT FROM AUTHOR]