A comparison of various double loops frequency selective surfaces in terms of angular stability

This paper presents the comparison of Frequency Selective Surfaces (FSS) structure performance based on three different double loops: square, circular and hexagonal structures. The simulation process of the double loops FFS structures are carried out by using the Computer Simulation Technology (CST) Microwave Studio software. The dielectric substrate used in the simulation is the FR-4 lossy substrate

Hole making process of carbon fiber reinforced polymer (CFRP) using end mill cutting tool

This paper presents an alternative way of producing a hole by using a helical milling concept on a carbon fiber reinforced polymer (CFRP). Delamination is a major problem associated with making a hole by drilling on the CFRP. This study focused on helical milling technique using a vertical machining center in order to produce a hole. Various levels of cutting parameter such as cutting speed, feed rate and depth of cut have been chosen to observe the effect of trust force, delamination and surface roughness. The result will be used to determine on which cutting parameters give the best hole quality that will achieved by this new approached

VHDL Based Maximum Power Point Tracking of Photovoltaic Using Fuzzy Logic Control

It is important to have an efficient maximum power point tracking (MPPT) technique to increase the photovoltaic (PV) generation system output efficiency. This paper presents a design of MPPT techniques for PV module to increase its efficiency. Perturb and Observe method (P&O), incremental conductance method (IC), and Fuzzy logic controller (FLC) techniques are designed to be used for MPPT. Also FLC is built using MATLAB/ SIMULINK and compared with the FLC toolbox existed in the MATLAB library. FLC does not need knowledge of the exact model of the system so it is easy to implement. A comparison between different techniques shows the effectiveness of the fuzzy logic controller techniques.  Finally, the proposed FLC is built in very high speed integrated circuit description language (VHDL). The simulation results obtained with ISE Design Suite 14.6 software show a satisfactory performance with a good agreement compared to obtained values from MATLAB/SIMULINK. The good tracking efficiency and rapid response to environmental parameters changes are adopted by the simulation results

Cakar ayam shaping machine

Cakar ayam (Figure 7.1) is one of the Malay traditional cookies that are made from sliced sweet potatoes deep-fried in the coconut candy. In current practice of moulding the cookies, the fried sweet potatoes are molded using traditional manual tools, which are inefficient and less productive for the mass production purposes. “Kuih cakar ayam” associated with the meaning of the idiom means less messy handwriting has a somewhat negative connotation .This cookies may just seem less attractive in shape but still likeable . In fact, this cookie is considered a popular snack even outside the holiday season. The choice of the name of this cookie is more to shape actually resembles former chicken scratches made by the paw the ground while foraging. The value of wisdom, beauty and creativity of the Malays is clearly evident through the Malay cookie. Although it is attacked by the invention of modern cakes that look far more interesting, these cakes will be able to survive a long time until now

An FPGA Kalman-MPPT implementation adapted in SST-based dual active bridge converters for DC microgrids systems

The design of digital hardware controllers for the integration of renewable energy sources in DC microgrids is a research topic of interest. In this paper, a Kalman filter-based maximum power point tracking algorithm is implemented in an FPGA and adapted in a dual active bridge (DAB) converter topology for DC microgrids. This approach uses the Hardware/Software (HW/SW) co-design paradigm in combination with a pipelined piecewise polynomial approximation design of the Kalman-maximum power point tracking (MPPT) algorithm instead of traditional lookup table (LUT)-based methods. Experimental results reveal a good integration of the Kalman-MPPT design with the DAB-based converter, particularly during irradiation and temperature variations due to changes in weather conditions, as well as a good balanced hardware design in complexity and area-time performance compared to other state-of-art FPGA designs

Fuzzy Controller Design Using FPGA for Sun and Maximum Power Point Tracking in Solar Array System

In this paper, Two fuzzy logic controllers are fabricated on modern FPGA card (Spartan-3AN, Xilinx Company, 2009) to increase the energy generation efficiency of solar cells. These controllers are, sun tracking controller and maximum power point tracking controller. Sun tracking generating power system is designed and implemented in real time. A tracking mechanism composed of photovoltaic module, stepper motor, sensors, input/output interface and expert FLC controller implemented on FPGA, that to track the sun and keep the solar cells always face the sun in most of the day time. The proposed sun tracking controller, and maximum power point tracking controller are tested using Matlab/Simulink program, Maximum power point tracking system is designed and implemented in real time. The results show that both controllers have a response better than conventional controller applied on the same system

Sustav za efikasno upravljanje solarnom energijom

Solar power is the major renewable energy source opted by developing countries as stand-alone / Grid enabled system. Industries and educational institutions are opting for solar energy to combat power crisis. This paper proposes knowledge based, self configurable, smart controller to efficiently use solar energy according to load, under frequent grid failure environment. It is enabled with fault identification and isolation. Extension to higher power capacity is easily achieved with plug and play mechanism. Proposed control architecture is implemented using Field Programmable Gate Array (FPGA), that supports modular level implementation with well defined interfaces for each sub-system. It can be used with low power as well as high power photo-voltaic system. Efficiency of the proposed architecture is demonstrated for the photo-voltaic system installed in educational institution.Solarna energija spada među glavne obnovljive izvore energije odabrana od strane zemalja u razvoju kao samostalnih izvora ili umrežene s ostalim izvorima. Industrija i edukacijske institucije predlažu solarnu energiju u borbi protiv energetske krize. U ovome radu predstavljen je samokonfigurabilan regulator za efikasno korištenje solarne energije s obzirom na opterećenje i česte promjene u mreži. To je omogućeno uz identifikaciju kvara. Ekstenzija na visoke snage jednostavno se postiže sa uređajem koji se može odmah koristiti. Regulator je implementiran koristeći programirljive logičke sklopove (FPGA) koji podržavaju modularnu implementaciju svake razine sa sučeljem prema svakom podsustavu. Predloženi sustav može biti korišten za niske snage kao i za visoke snage kod fotonaponskih sustava. Efikasnost predložene arhitekture testirana je na fotonaponskom sustavu postavljenom na edukacijskoj instituciji

Fuzzy Control Based Renewable Energy Sources for DC Microgrid Applications using FPGA Platform with EMS

The main objective of this proposed system is to provide uninterruptible power supply to the load.  This proposed system mainly deals with the Energy Management System (EMS) of the DC microgrid systems, using the fuzzy logic control.  This proposed system consists of the power sources, which obtains its power from the PV panels, Wind turbine, and fuel cells stack.  The EMS incorporates the fuzzy control that is responsible for the Energy Management and Battery Management.  The fuzzy maintains the State of Charge (SoC) parameters of the battery.  The fuzzy logic implementation of this system was done by using the Field Programmable Gate Array (FPGA)

Maximum Power Point Tracking in PV Arrays with High Gain DC-DC Boost Converter

Photovoltaic (PV) system is an electricalgenerator that has been widely used. Ease of implementation,supported by a large number of potentials and needs of GreenEnergy, has become a factor in the increasing number andquickly applied to PV arrays. However, PV arrays haveconstrained related to generator conversion efficiency and theamount of power produced due to inconstant irradiation andtemperature. This problem can be solved by a MaximumPower Point Tracking (MPPT) approach. This article discussesthe MPPT technique with High Gain DC-DC Boost Converterusing the Perturb and Observe (P&O) algorithm. The sameP&O algorithm is also tested in the conventional converter toshow performance and superiority of each converter. Theresults obtained show the advantages and disadvantages ofeach converter used in MPPT by P&O algorithm

Proposed Algorithm MPPT for Photovoltaic System

A proposed algorithm MPPT (Maximum Power Point Tracking) is proposed in this paper. When the insolation change rapidly, the P&O (Perturb and Observe) algorithm is used to adjust the operating point of the PV (Photovoltaic) array close to the MPP (Maximum Power Point) for fast tracking; also, the INC (Incremental Conductance) algorithm and the fuzzy controller skip drawbacks of the P&O algorithm by decreasing oscillations around the MPP and the underestimated. In addition, to improve the control precision, the effectiveness of proposed algorithm is validated by simulation using Matlab/Simulink, the simulation results show that the proposed algorithm tracks the MPP quickly, reduces the oscillation around the MPP effectively and improves the energy conversion efficiency of the PV panel