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Ecological and Economical Friendly Analysis of A Hybrid Solar-Grid-Diesel Connected Power Generation System
No full textThis paper presents Importance of hybrid power system. This paper depicts model and simulation of a renewable energy based hybrid power system for improving power quality because optimal utilization of primary energy sources will increase the level of supply reliability. The combination of Grid, Photo Voltaic (PV) Array System, and Diesel generator systems are used for power generation. Due to variation in output power of solar panel, Diesel engine is also coupled to ensure reliable supply under all conditions. The results shows that the proposed hybrid power system can effectively manage the optimal utilization of primary energy sources and improves the power quality in an islanding as well as grid connected mode
An Enhanced Control Strategy for the Stable Operation of Distributed Generation during Grid-Connected and Islanded Mode
No full textThe incident of islanding occurs while the distributed generator fed constant power into the grid after power flow on the source of essential utility has been intermittent. If islanding is not rapidly detected, it can reason serious security and harmful condition. This paper presents coordinated manage of solar photovoltaic unit through maximum power point tracking technique to make available voltage and frequency support for an islanding condition. In normal condition, structure works as constant current control mode subsequent to islanding the structure switched to voltage control mode. The projected technique is capable to discriminate involving an islanding and a non-islanding occurrence. In this paper phase locked loop detection technique designed for detecting islanding situation is conceded out. The authentication of proposed system is established efficiently using MATLAB/ Simulink environment. The simulated results exhibit that the islanding detection technique has zero nondetection zone property and be able to detect islanding within few second
Frequency Reconfiguration Mechanism of a PIN Diode on a Reconfigurable Antenna for LTE and WLAN Applications
No full textMicrostrip patch antennas are increasingly gaining popularity for usage in portable wireless system applications due to their light weight, low profile structure, low cost of production and robust nature. The patch is generally made of a conducting material such as copper or gold and can take any possible shapes, but rectangular shapes are generally used to simplify analysis and performance prediction. Microstrip patch antenna radiates due to the fringing fields between the patch edge and ground plane. In this work, a frequency reconfigurable antenna with a BAR63-02V Positive-Intrinsic-Negative (PIN) diode is designed, simulated and fabricated. The antenna operates at 2.686 GHz for Long-Term Evolution (LTE2500) and 5.164 GHz for Wireless Local Area Network (WLAN) applications. In the OFF state, the antenna operates at 5.302 GHz, which is also suitable for WLAN application. The proposed antenna is fabricated on a FR-4 substrate with a relative dielectric constant, εr of 4.5, thickness, h of 1.6 mm and loss tangent, tan δ of 0.019. The fabrication process is carried out at the Advanced Printed Circuit Board (PCB) Design Laboratory in UTHM
The Utilization of Physics Parameter to Classify Histopathology Types of Invasive Ductal Carcinoma (IDC) and Invasive Lobular Carcinoma (ILC) by using K-Nearest Neighbourhood (KNN) Method
No full textMedical imaging process has evolved since 1996 until now. The forming of Computer Aided Diagnostic (CAD) is very helpful to the radiologists to diagnose breast cancer. KNN method is a method to do classification toward the object based on the learning data which the range is nearest to the object. We analysed two types of cancers IDC dan ILC. 10 parameters were observed in 1-10 pixels distance in 145 IDC dan 7 ILC. We found that the Mean of Hm(yd,d) at 1-5 pixeis the only significant parameters that distingguish IDC and ILC. This parameter at 1-5 pixels should be applied in KNN method. This finding need to be tested in diffrerent areas before it will be applied in cancer diagnostic.
A New Hybrid Robust Fault Detection of Switching Systems by Combination of Observer and Bond Graph Method
No full textIn this paper, the problem of robust Fault Detection (FD) for continuous time switched system is tackled using a hybrid approach by combination of a switching observer and Bond Graph (BG) method. The main criteria of an FD system including the fault sensitivity and disturbance attenuation level in the presence of parametric uncertainties are considered in the proposed FD system. In the first stage, an optimal switching observer based on state space representation of the BG model is designed in which simultaneous fault sensitivity and disturbance attenuation level are satisfied using H=H1 index. In the second stage, the Global Analytical Redundancy Relations (GARRs) of the switching system are derived based on the output estimation error of the observer, which is called Error-based Global Analytical Redundancy Relations (EGARRs). The parametric uncertainties are included in the EGARRs, which define the adaptive thresholds on the residuals. A constant term due to the effect of disturbance is also considered in the thresholds. In fact, a two-stage FD system is proposed wherein some criteria may be considered in each stage. The efficiency of the proposed method is shown for a two-tank system
Comparative Analysis of Linear Controllers used for Grid Connected PV System
No full textRequirement for electrical energy is increasing in a ramp function manner. To meet the steady increasing in energy demand it is required to find some alternate source of energy. Except the conventional source of energy one type of renewable energy i.e PV may be regarded as a clean source of energy to meet the energy demand. PV modules generating DC power cannot be directly connected to the electrical infrastructure as most of the grid infrastructure uses either 230volt or 120 volt. Therefore power electronic device most be connected (inverter) between PV and grid. In order to make a competitive market between the renewable generated power and conventional way of generating the power it is required to design a cost effective inverter, qualitative output which is pure sinusoidal and harmonics free. In this paper a comparative analysis among the various linear controllers are presented. Proposed Optimised PID Controller is Presented through MATLAB Simulink based environment
Modeling and Simulation of Fuzzy Logic based Maximum Power Point Tracking (MPPT) for PV Application
No full textThis paper presents modeling and simulation of maximum power point tracking (MPPT) used in solar PV power systems. The Fuzzy logic algorithm is used to minimize the error between the actual power and the estimated maximum power. The simulation model was developed and tested to investigate the effectiveness of the proposed MPPT controller. MATLAB Simulink was employed for simulation studies. The proposed system was simulated and tested successfully on a photovoltaic solar panel model. The Fuzzy logic algorithm succesfully tracking the MPPs and performs precise control under rapidly changing atmospheric conditions. Simulation results indicate the feasibility and improved functionality of the system
A Triple Band Bow Tie Array Antenna Using Both-sided MIC Technology
No full textA single-fed linearly polarized 2x2 microstrip bow tie array antenna is proposed. The feed network has microstrip line and slot line where microstrip-slot branch circuit is connected in parallel. The feed network of the array is designed using both-sided MIC Technology to overcome the impedance matching problem of conventional feed networks. The 2x2 half bow tie array antenna is also truncated with spur lines for optimization of antenna performance. The array antenna unit can be realized in very simple and compact structure, as all the antenna elements and the feeding circuit is arranged on a Teflon glass fiber substrate without requiring any external network. The design frequency of the proposed antenna is 5 to 8 GHz (C-Band) and the obtained peak gain is 12.41 dBi. The resultant axial ratio indicates that linear polarization is achieved
A Framework for Optimizing the Process of Energy Harvesting from Ambient RF Sources
No full textEnergy harvesting has been an active research topic in the past half a decade with respect to wireless networks. We reviewed some of the recent techniques towards improving energy harvesting performance to find that there is a large scope of improvement in terms of optimization and addressing problems pertaining to low-powered communicating mobile nodes. Therefore, we present a framework for identifying available RF sources of energy and constructing a robust link between the energy source and the mobile device. We apply linear optimization approach to enhance the performance of energy harvesting. Probabilility theory is used for identification of event loss in the presence of different number of nodes as well as node distances. The objective of the proposed system is to offer better availability of RF signals as well as better probability of energy harvesting for mobile devices. The proposed technique is also found to be computationally cost effective
Unbalanced Voltages Impacts on the Energy Performance of Induction Motors
No full textThis paper presents the results of a study about the effects of unbalanced voltages on the energy performance of three-phase induction motors. The principal contribution of this paper is that presents a detailed analysis of the influence of positive and negative sequence voltage components and the angle between them on several characteristics such as: line currents, losses, efficiency and power factor under different voltage unbalanced conditions. A three-phase induction motor of 3 HP was used as a case study. The results of the investigation show that the positive sequence voltage must be considered together with the voltage unbalance factor (VUF) or percent voltage unbalance (PVU) index to evaluate the performance of the induction motor. It is also shown that the behavior of the motor load influences on the positive sequence parameters next to the voltage, while in the case of negative sequence only influences the negative sequence voltage