Performa Konfigurasi Modul Surya Seri dan Seri Paralel pada Kondisi Mismatch Karakteristik Arus-Tegangan (I-V) terhadap Daya Output

The installation of a Solar Power System (PLTS) within the ideal conditions still uses the type of solar module with the same current and voltage characteristics. However, these ideal conditions can be different if the commonly used modules are no longer available on the market. Once there is damage or interference in the operating system, such as cracks in the module plate, it will take a significantly long time to replace. This particular condition can obstruct electrical power distribution to its intended loads in the other end. Therefore, creating a robust solar panel system that operates at its maximum capacity requires an alternative or approach to find such a similar module replacement. It is expected that the replacement module will have the I-V characteristics, which relatively resemble that of the earlier module and can help to maintain the energy availability of the solar panel system. This study aims to analyze which factors affect the characteristic irregularity of currents and voltages in a solar panel installation towards the output of a solar panel under certain conditions. The solar panel system is designed using 20 solar modules with each capacity is 250 WP power that is simulated with Simulink. The method creates the mismatch condition of the current and voltage on the solar module in a specific panel configuration. These mismatch conditions are created by combining solar modules with different currents and voltages in the Series (S) and Series-Parallel (SP) configurations. The simulation is carried out by replacing the main solar module with a 5% to 100% replacement solar module. The selection of the replacement module is based on Isc, which is close to the same because the current flowing in the series circuit is the same. The simulation results showed that the solar panel system still functioned properly and produced maximum power under mismatch conditions. Of all three configurations with mismatch conditions, it is found that the best performing configuration works with the Series-Parallel (SP) configuration of the STC conditions. The maximum power which can be sustained with Series-Parallel (SP) configuration reaches up to 40% of the original modules

A hierarchical architecture for increasing efficiency of large photovoltaic plants under non-homogeneous solar irradiation

Under non-homogeneous solar irradiation, photovoltaic (PV) panels receive different solar irradiance, resulting in a decrease in efficiency of the PV generation system. There are a few technical options to fix this issue that goes under the name of mismatch. One of these is the reconfiguration of the PV generation system, namely changing the connections of the PV panels from the initial configuration to the optimal one. Such technique has been widely considered for small systems, due to the excessive number of required switches. In this paper, the authors propose a new method for increasing the efficiency of large PV systems under non-homogeneous solar irradiation using Series-Parallel (SP) topology. In the first part of the paper, the authors propose a method containing two key points: a switching matrix to change the connection of PV panels based on SP topology and the proof that the SP-based reconfiguration method can increase the efficiency of the photovoltaic system up to 50%. In the second part, the authors propose the extension of the method proposed in the first part to improve the efficiency of large solar generation systems by means of a two-levels architecture to minimize the cost of fabrication of the switching matrix

Analysis of AC-DC Converter Circuit Performance With Difference Piezoelectric Transducer Array Connection

This research presents a simulation analysis for the AC-DC converter circuit with a different configurations of the array connection of the piezoelectric sensor. The selection of AC-DC converter circuits is full wave bridge rectifier (FWBR), parallel SSHI (P-SSHI) and parallel voltage multiplier (PVM) with array configuration variation in series (S), parallel (P), series-parallel (SP) and parallel-series (PS). The system optimizes with different load configurations ranging from 10 kΩ to 1 MΩ. The best configuration of AC-DC converter with an appropriate array piezoelectric connection producing the optimum output of harvested power is presented. According to the simulation results, the harvested power produced by using P-SSHI converter connected with 3 parallel piezoelectric transducer array was 85.9% higher than for PVM and 15.88% higher than FWBR

Investigation of magnetic resonance coupling circuit topologies for wireless power transmission

© 2019 Wiley Periodicals, Inc. Magnetic resonance coupling circuits have four general topologies; however, there is a lack of comprehensive theoretical analysis with experimental verification for each of these topologies regarding their attractiveness for wireless power transfer (WPT). This article provides this for each of the four topologies to fully understand their differences and allow the selection of the most appropriate type based on system requirements. In addition, a problem associated with the resonance coupling method is the phenomenon of frequency splitting, which can lead to a high-power transfer efficiency but low-load power at the resonant frequency. Reasons for frequency splitting and methods of circumventing the problem will be illustrated in this article. Of the four topologies, the series-parallel (SP) (input-output) circuit configuration is the most efficient for the realization of a WPT system with a large load impedance, in terms of achieving both a high power transfer efficiency and high-load power

Intrinsic-Capacitance-based Differential Power Processing for Photovoltaic Modules

Partial shading reduces energy production and affects the lifetime of the overall PV system. To mitigate the mismatch effects caused by partial shading, several PV cell- or sub-panel-level techniques employing power electronics have been proposed in the literature, where discrete passive components, e.g., inductors and capacitors, are also used. In this paper, a differential power processing (DPP) technique, which utilizes only the intrinsic capacitance of solar cells, is introduced for small-scale PV applications. The developed DPP topology mitigates the mismatch effects by operating all PV cells at or near to their corresponding maximum power points (MPPs) even under mismatch conditions. The analysis of the topology and its comparison with the frequently used series- and series-parallel (SP)-connected techniques, are presented to validate its efficacy and operational capabilities, through simulation results. Moreover, a prototype is built to verify the topology. The experimental results confirm the elimination of multiple power peaks under mismatch along with maintaining the same voltages across the PV panels.</p

Bounds on series-parallel slowdown

We use activity networks (task graphs) to model parallel programs and consider series-parallel extensions of these networks. Our motivation is two-fold: the benefits of series-parallel activity networks and the modelling of programming constructs, such as those imposed by current parallel computing environments. Series-parallelisation adds precedence constraints to an activity network, usually increasing its makespan (execution time). The slowdown ratio describes how additional constraints affect the makespan. We disprove an existing conjecture positing a bound of two on the slowdown when workload is not considered. Where workload is known, we conjecture that 4/3 slowdown is always achievable, and prove our conjecture for small networks using max-plus algebra. We analyse a polynomial-time algorithm showing that achieving 4/3 slowdown is in exp-APX. Finally, we discuss the implications of our results.Comment: 12 pages, 4 figure

Sensitivity Analysis of a Bidirectional Wireless Charger for EV

Bidirectional chargers are required to fully integrate Electric Vehicle (EV) into the smart grids. Additionally, wireless chargers ease the charge/discharge process of the EV batteries so that they are becoming more popular to fulfill a V2G scenario. When considering the load of wireless chargers, it is a requirement to know the real output power that these systems offer. The designed output power may differ from the real one as components suffer from tolerance. This paper defines six sensitivity factors to model the severity of the effects of tolerance into the output power. To do so, an electric circuit analysis is used and a mathematical formulation is derived. The six sensitivity factors are computed for a laboratory prototype.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech