This Photovoltaic system to track the maximum power point. The Backstepping controller is used to designed for applied the boost dc converter to improve its performances and to achieve optimal Photovoltaic array output voltage. The Vref is to be provided perturb and observe method. This Lyapunov function is controlled based on the local stability of the sys.tem. grid-connected inverters is used for photovoltaic system to performance modeling and for continuous monitoring of inverter performance during system operation. Hence to prove the maximum power extraction of the system is guaranty. The backstepping method is to be sustain the stability of the converter in wide range of the variations in temperature, radiation.. etc. Simulations used to demonstrate the efficiency in the presence of the environmental perturbations.Keywords: Backstepping, Boost converter, Photovoltaic system, maximum power point, PV grid connected system, Lyapunov stability.
Over recent decades because of many drawbacks of conventional energy sources like higher fossil fuel prices, harmful environmental damage, shortage of sources and increasing pollution the need to use renewable sources of energy has grown over recent decade. Seeing the needs of future generations, in recent decades, non-conventional energy resources are the core center of research investigative work. Among all other non-conventional energy sources wind energy conversion system is come out to be the most cost effective and the preferred alternative for power generation. As the wind has arbitrary and unpredictable nature, it is important that few kind of control strategy has to be introduced to obtain maximum power from the generated power from PMSG. Therefore, to obtain maximum power as possible from wind during uneven wind speed or wind speed variation, tracking controller for maximum power point tracking is employed. This paper represents a system model for a grid connected 3KW PMSG wind turbine system along AC-DC-AC conversion stages. Major object is to extract the maximum energy from the wind which confirms a highest efficiency of proposed work. First, mathematical modeling of wind turbine and PMSG are illustrated in this thesis. Among numerous methods available, the most competent technique of maximum power point tracking is Perturbation and observation (P&O) that has its own qualities. Complete system modeling is carried out by MATLAB & Simulink. Proposed system simulation evaluation is performed to ensure operation of maximum power point tracking and effectively extract maximum power generated throughout the variation in wind speed. Wind speed variation, causes disturbance in system frequency and voltage that results in generation losses. So to decrease significant variation in the system frequency and voltage, a voltage & frequency controller is also used to operate with voltage source converter (VSC). The implementation of the given system is evaluated for various profile of wind speed. A grid connected permanent magnet synchronous generator based WESC is designed, modeled & simulated with MATLAB & SIMULINK.Keywords: Maximum Power Point Tracking, MPPT Algorithm,WECS.
Shiyali Ramamrita Ranganathan introduced a number of classical theories and their practical applications with laws, rules and regulations. In this paper, I mainly applied the philosophical oath of Hippocrates and the philosophical thought of Plato in Library Science for the betterment of library and information centres more user-friendly, user-oriented and also more practical.Keywords: Bentham, Hippocrates, Library science , Philosophy, Plato.
Addressing the stability problem through Single machine infinite bus system is a quite simple and easy to understand. For a more practical approach Multi-machine system would be more beneficial giving the close insight of the real world situation of instability. In such a situation a power system must be able to maintain frequency and voltage level. SO is the case with presented work where a multi-machine system is considered under low frequency oscillations. If such an oscillation persists for a long period of time could lead to separation of a system in the absence of appropriate. It could be damped out by Power system Stabilizers (PSS) which is very effective and generally used controller in such a case. It enhances the stability limit and damping capability of the system. But it performance could further be optimized by the use of suitable optimization method. The method used here is the artificial intelligence (AI) based JAYA algorithm. The presented work uses the platform provided by MATLAB/SIMULINK to develop the multi machine system consisting 3 machines and 9 bus system, hence making it a 3 machine 9 bus system. This system in cooperates the JAYA based PSS which was analyzed under normal, light and heavy loading conditions respectively by applying three phase fault. The results are obtained in terms of speed deviation, change in generator speed and stabilizing signal deviation settling time. The results are compared with the results of system using Conventional PSS and system without any controller to verify its effectiveness and robustness.Keywords:
The purpose of this paper is to provide an overview of social media usage for Products marketing and how the online customers had gone through with these platforms. This study also finds out the customer’s behavior about the using social media in their products purchase decision making. This paper also examines the firm’s behavior about using the social media in their business progression. This paper provides information regarding the influence of social media on businesses. Paper also highlights the current use of social media among firms and customers. The authors try to address the number of area like characteristics, benefits, issues and needs of social media in online shopping or products marketing.Keywords: Social media, Marketing, Customers, Shopping, Products.
This paper presents the comparative study of zero voltage switching full bridge inverter with various controller schemes. The switching waveform of the MOSFET produced by various controllers like PI controller, PID controller, DSP Controller, fuzzy logic controller etc. to obtain maximum output voltage and efficiency. Soft-switching techniques have been applied in the design of inverters, in order to achieve superior performance, maximum efficiency with variation of load. A significant number of new techniques for different applications have been presented. This paper is an attempt to classify the soft-switched dc–ac topologies in a simple and generic way with various controller schemes. The technique classifications are based on the location of the resonant network, the characteristic of switching waveforms (zero-voltage switching or zero-current switching), and the type of resonance (series or parallel). Operating principles, performance, and design limitations are discussed. The ZVS condition achieve for switches presented in circuit for large range of power to obtain maximum efficiency.Keywords: Digital Signal Processor (DSP), Metal Oxide Semiconductor Field Effect Transistor (MOSFET), Proportional Integrator (PI), Proportional Integral Derivative (PID), Pulse Width Modulation (PWM), Zero-current switching (ZCS), Zero-Voltage switching (ZVS).