Applied Mechanics and Materials Vol. 785

Abstract: In this paper, we have developed transmitter, receiver and 2 structure magnetic resonant couplings. Both of the Transmitter and Receiver couplings are made of copper tubing. Transmitter and Receiver circuits were build by using Multisim software. Transmitter in put by DC source 12 Volt, 0.5 Ampere, with 50 cm Air gap wireless power transfer can reach efficiency 25.2 % with DC 3.02 Volt, 50.01 mA, at Frequency 164.76 kHz.

Abstract: Switches fault in power converter has become compelling issues over the years. To reduce cost and maintenance downtime, a good fault detection technique is an essential. In this paper, the performance of STFT and S transform techniques are analysed and compared for voltage source inverter (VSI) switches faults. The signal from phase current is represented in jointly time-frequency representation (TFR) to estimate signal parameters and characteristics. Then, the degree of accuracy for both STFT and S transform are determined by the lowest value of mean absolute percentage error (MAPE). The results demonstrate that S transform gives better accuracy compare to STFT and is suitable for VSI switches faults detection and identification system.

Abstract: The maximum output power of a photovoltaic (PV) system with a DC-DC converter depends mainly on the solar irradiance (G) and the temperature (T). Therefore, a maximum power point tracking (MPPT) mechanism is required to improve the overall system. The conventional MPPT approaches such as the perturbation and observation (P&O) technique have difficulty in finding true maximum power point. Thus various intelligent MPPT systems such as fuzzy logic controllers (FLC) are recently introduced. In FLC based MPPT, selecting the type of the membership function (MF) and the number of the fuzzy sets (FS) is critical for better performance. Thus, in this paper various adaptive neuro fuzzy inference system (ANFIS) is utilized to automatically tune the FLC membership functions instead of adopting the trial and error method. To find suitable MF for FLC, ANFIS is developed in MATLAB/Simulink and the effect of different types MF investigated. Simulation result shows that the FLC with triangular MF and seven FS give the best result. The evaluation indices used in this study includes the maximum extracted energy, minimum standard deviation of the error, and minimum mean square error.

Abstract: This paper presents the investigation of partial shading characteristics of mono-crystalline and poly-crystalline photovoltaic module connected in series. Simulink models are developed to assist the investigation to determine the ideality factor for mono-crystalline and poly-crystalline photovoltaic module. Commercially available mono-crystalline and poly-crystalline photovoltaic module are used to extract measurable parameters for the model to study the behaviour of I-V curve. Measurements have been conducted for the investigation including mono-crystalline only, poly-crystalline only, both unshaded, mono-crystalline shaded and poly-crystalline shaded. This paper contributes to the understanding of partial shading characteristics of different materials presence in photovoltaic string.

Abstract: since PV inverter cost and performance in residential Solar System Application is a controversial subject, it always needs to be researched to encounter the challenges of cost competitions especially with environmentally polluted fossil fuel energy expense. This research proposes a fundamentally novel solutions for utilizing the unavoidable solar system losses by the hypothesis of dispensing the power converters in domestic application of home solar system. This hypotheses based on matching methods between the energy source, the Battery bank, and the load, home appliances. Since the energy source is a direct current DC supply, this matching process would be via evaluating of the normal alternative current AC appliances and compatibility range to be switched on DC supply, the operation of the appliances evaluated individually with DC supply either by direct coupling or with simple modification, the analysis of the data have been accumulated in terms of efficiency. Individually, appliances were classified according to different aspects in such a way that shows its compatibility range with the DC power supply. A comparison results for each classified appliances have been done for both operation conditions AC and DC. The efficiency of a relatively good quality Inverter would be referred to see what gain would be obtained from switching to DC supply-load matching when eliminating of AC Inverter from the system. A sequence of processes have been carried out on home appliances individually in terms of its electrical and electronic composition towards best system performance and reasonable cost. MATLAB Simulink has been used as a simulation program. The results shows; great utilization of the home solar system losses, cost and faults probability reduction, high efficiency, and more reliable system.

Abstract: The continuously increasing use of photovoltaic cells requires various efforts to maximize the harnessing of solar energy. This paper presents the research results of fuzzy-logic method implementation to maximize the absorption of solar energy. It is based on the optimization of solar panels position according to the sun direction. The Takagi-Sugeno method is chosen in the fuzzification stage. The control algorithm is implemented on a microcontroller ATMega-128 using BASCOM-AVR program. DC motor is used to actuate the solar panels. The results show an increase of 0.48V in the output of solar cells sensor using the fuzzy logic computation-based tracking system. The resulted tracking system proves to consume less power because the tracking process is halted while moving the DC motor continuously.

Abstract: A new method for monitoring and control of domestic distribution box is proposed and developed for automated recovery of power continuity during interruption. The system automatically test each of the sockets to determine the source of the failure and isolate them. The data of the modified connection will be sent to the client through a server, wirelessly to notify the user the modifications made. Parallel processing via multi-threading in the server are used to increment the upper limit of TCP transmission's throughput. Multiple SQLite database are used by multiple threads for parallel storage of data to increase performance.

Abstract: This paper presents an efficiency comparison and verification of two types of Brushless DC (BLDC) motors and drives combination. The trapezoidal BLDC motor is excited by trapezoidal drive and sinusoidal BLDC motor is excited by sinusoidal drive. In air conditioner fan motor system, the sinusoidal type of BLDC motor with sinusoidal drive is applied. However, the DC link voltage of the motor is high and thus demands for high power consumption. Furthermore, the sinusoidal drive use vector control which is complicated to be implemented and make the driver high cost. Therefore, further improvement in energy consumption and drive system is required by develop combination of trapezoidal BLDC motor with trapezoidal drive. Thus, these two combination motors and drives required for efficiency comparison. The motors drives are simulated by using MATLAB and then their efficiencies are measured. At the end of this paper, the results show that the trapezoidal BLDC motor with trapezoidal drive offers higher efficiency compared to sinusoidal BLDC motor with vector control drive. It indicates that the developed drive system is considerable to be applied in the air conditioner fan motor system.

Abstract: This paper compares overall efficiency of trapezoidal BLDC motor which is excited by trapezoidal drive and sinusoidal drive. The different characteristics and performance of trapezoidal Brushless DC (BLDC) motor is formed by driving methods. Sinusoidal drive that excites trapezoidal BLDC motor generates greater maximum torque than trapezoidal drive. However, with regard to high frequency loss caused by a pulse width modulation (PWM) carrier and switching loss, the trapezoidal drive has potential to achieve higher efficiency than the sinusoidal drive. Thus, these two drive methods excite trapezoidal BLDC motor are compared to study the efficiency performance. The motors drives are simulated by using MATLAB and their efficiency are measured. The results show that the trapezoidal BLDC motor with trapezoidal drive has higher efficiency compared to trapezoidal BLDC motor with sinusoidal drive.

Abstract: This paper discusses the optimal Distributed Generator (DG) coordination using the Particle Swarm Optimization (PSO) technique where the DG output and location are determined simultaneously. Furthermore, this study analyzes both single DG and multiple DGs configurations. The influence of DG Power Factor (PF) to the optimal DG placement and the DG output are investigated by varying the DG PF values. Specifically, the PF were configured to five values, which are 0.8, 0.85, 0.9, 0.95 and 1.0. From the results, the optimal DG placements are similar, regardless of the PF condition. For example, in the single DG unit experiment, the optimal DG location is at bus 6 whilst in the triple DG units test, the optimal locations are at busses 14, 24, and 30. In contrast, the value of PF significantly influences the optimal DG output and power loss reduction. This study concludes that the design with three DGs where their PFs are configured to 0.8 has the least power loss.