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

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

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

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

Low cost microcontroller implementation of Takagi–Sugeno Fuzzy MPPT controller for photovoltaic systems

Maximum power point trackers have a significant role in optimizing the energy conversion efficiency in a photovoltaic system. The numeric achievements of MPPT algorithm can be implemented and tested by using several embedded boards as Digital Signal Processor, Field-Programmable Gate Array, Arduino, and dspace. Alternatively, for the low cost, availability and simplicity, the PIC microcontrollers can be used compared with the other hardware devices. Therefore, this paper presents the implementation of a Takagi–Sugeno fuzzy controller on a low cost PIC microcontroller, for tracking the maximum power point of a PV module. The PV system consists of a PV emulator, DC-DC converter, and resistive load. The different steps in design, simulation and realization of the T-S Fuzzy logic controller are discussed. The proposed controller system was evaluated by comparing its performance metrics, in terms of efficiency and the Integral Square Error, with existing technique in the literature. The results corresponding to the experimental validation show that the proposed MPPT controller is able to ensure a perfect tracking of the maximum power point with variation of irradiance and is performing better than reported in a previous work

A real time simulation of a photovoltaic system with maximum power point tracking

International audienceThis work presents an experimental stand for the study of a power electronics control system to locate and track the maximum power point of a photovoltaic (PV) array to ensure efficient power transfer from the solar cells to the load under varying environmental conditions. A real-time photovoltaic solar cell measurements and a control system was developed to guarantee that the maximum power output is attained. This stand is built at the Electrical Machinery Laboratory of “Vasile Alecsandri” University of Bacau, Romania

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

A Review on Photo Voltaic MPPT Algorithms

A photovoltaic generator exhibits nonlinear voltage-current characteristics and its maximum power point varies with solar radiation and cell temperature. A Dc/Dc power converter is used to match the photovoltaic system to the load and to operate the PV (photo voltaic) cell array at maximum power point. Maximum Power Point Tracking (MPPT) is a process which tracks one maximum power point from PV array input, varying the ratio between the voltage and current delivered to get the most power it can. There are different techniques proposed with lot of algorithms are being used in the MPPT controller to extract the maximum power. It is very difficult for the photo voltaic designers, researchers and academic experts to select a particular MPPT technique for a particular application which requires the background knowledge and comparative features of various MPPT algorithms. This paper will be avaluable source for those who work in the photo voltaic generation, so its objective is to review the main MPPT algorithms in practice and analyzes the merits and demerits with various factors