Indexing

Abstract: Power system can be simulated and analyzed based on a mathematical model however; uncertainty still exists due to change of loads and an occurrence of fault. Recently, fuzzy theory highly flexible easily operated and revised, theory is a better choice, especially for a complicated system with many variables. Hence, this work aims to develop a controller based on fuzzy logic to simulate an automatic voltage regulator in transient stability power system analysis. By adding power system stabilizer for tuning of fuzzy logic stabilizing controller there is no need for exact knowledge of power system mathematical model. The fuzzy controller parameters settings are independent due to nonlinear changes in generator and transmission lines operating conditions. Because of that proposed fuzzy controlled power system stabilizer should perform better than the conventional controller. To overcome the drawbacks of conventional power system stabilizer (CPSS), numerous techniques have been proposed in the article. The conventional PSS's effect on the system damping is then compared with a fuzzy logic based PSS while applied to a single machine infinite bus power system.

Abstract: This paper investigates the problem of controlling and modulating power flow in a transmission line using a Synchronous Static Series Compensator (SSSC). The studies, which include detailed PWM techniques controlled for SSSC, are conducted and the control circuits are presented. In this study, a static synchronous series compensator (SSSC) is used to investigate the effect of this device in controlling active and reactive powers as well as damping power system oscillations in transient mode. The SSSC equipped with a source of energy in the DC link can supply or absorb the reactive and active power to or from the line. Simulations have been done in MATLAB/SIMULINK environment. Simulation results obtained for selected bus-2 in two machine power system shows the efficacy of this compensator as one of the FACTS devices member in controlling power flows, achieving the desired value for active and reactive powers, and damping oscillations appropriately.

Abstract: This paper presents a comparative study of Generic Algorithm (GA) and Partical Swarm Optimization (PSO) technique for determining the optimal parameters of (PI) controller for speed control of a brushless DC motor (BLDC) where the (BLDC) motor is modeled in simulink in MATLAB. The proposed technique was more efficient in improving the step response characteristics as well as reducing the steady-state error, rise time, settling time and maximum overshoot.

Abstract: There are three types of DC/AC inverters available on the market, which are classified by their output types: (1) in practice, DC/AC conversion is done with topologies of varying precision. It can be as simple as applying voltages of equal magnitude in opposite directions across a load to generate a square wave. It is a square wave inverter. (2) A more precise method of DC/AC conversion is the modified sine wave, which introduces a dead time in a normal square wave output so that higher peak voltage can be used to produce the same average voltage as a sinusoidal wall-outlet output. This method produces fewer harmonics than square wave generation, but it still is not quite the same as the AC power that comes from AC outlet. The harmonics that are still present in a modified sine wave makes this type of inverter unsuitable for use while electrical noise is a concern, such as in medical devices which monitor the vital signs of a human.(3)Pure sine wave DC/AC conversion will introduce the least amount of harmonics into an electrical device, but are also most expensive method. Since the AC sine wave must come from a DC source, switching must still take place. However, switching takes place with logic so that the energy delivered to a load approaches that of a pure sine wave. This means that extra components and design considerations are involved in the control circuitry of a pure sine wave inverter, driving up cost.
In this paper an overview is presented of different PWM techniques to control the output voltage as well as to reduce the total harmonic distortion of output voltage in an H-bridge inverter.

Abstract: In the modern world, the demand of electricity is increasing day by day. The main reasons of increasing demand are the population, the economy growth and rapid depletion of fossil based energy reserve. Then it must research for an alternative source of power generation. One of the sources is a renewable energy which is not possibly harmful on environment. The need of power rating inverter is required to operate electrical and electronics appliances smoothly. Static UPS are virtually perfect electric generators. They are highly reliable and, by nature, ensure the uninterrupted availability of electric power. As regards electrical characteristics, the inverter (which constitutes the UPS generator) possesses from the point of view of frequency stability as well as voltage stability, performances superior to those of the mains. The only doubtful characteristic is, in the opinion of any engineer, its ability to deliver a sinusoidal voltage regardless of the shape of the current drawn by the load. Most of the available commercial uninterruptible power supplies (UPSs) are actually square wave inverter or quasi square wave inverters. Electronic devices, managed by these inverters will be damaged due to content of harmonics.In this paper a comparative harmonic distortion analysis is presented between and square wave and sine wave i.e. (MSPWM & SPWM) inverters.

Abstract:In this paper, A fuzzy logic based DVR model is presented and Modelled with the help of simulink block. Since from inception, fuzzy logic has been utilized in almost all the field but its application is mostly found very efficient in control system engineering. In this work Fuzzy logic controller is designed for DVR (Dynamic Voltage restorer) for mitigating the voltage sag and voltage swell problem. Simulation Result shows the compensation ability of this DVR is very effective.
Keywords: PI (Proportional Integration), VSC (Voltage Source Converter), DVR (Dynamic Voltage Restorer), SPWM (Sinusoidal Pulse Width Modulation).

Abstract: The entire world is facing a challenge to overcome the hurdle of energy crisis. It is fairly evident that a need exist for developing alternative energy sources. Amongst all the available renewable energy sources, solar energy appears to be a viable option as it is easily and widely available. If used in a proper way, it has a capacity to fulfill numerous energy needs of the world. Hence there is great scope of work in field of solar photovoltaic aiming at improved and efficient performances. Solar PV modules convert solar energy into electrical form but are having high non-linear current-voltage relationship which implies that they can operate at only one single point for maximum power. So extraction of maximum power in itself becomes a challenge under varying set of conditions of irradiation and temperature. A step by step approach is followed to analyze and address the problem with high frequency switching DC-DC converters that act as an interface between the module and the load and adjust the switching duty ratio so as to match the load line with that of Maximum Power Point load line. Further there exist various control algorithms to modify duty ratio. Their study is done and one such technique Incremental Conductance (IncCond) is used to process current and voltage of PV array to get the duty ratio. The results are obtained for changing radiation as well. In the present study, a review of Hill Climbing MPPT techniques, has been carried out with detailed flowcharts of algorithms and includes latest research papers published on MPPT techniques.

Abstract: Overhead transmission lines are an essential component of power systems, being the most economical means of transmitting electricity from remote sources of generation to the customer. It is therefore, vital that they be protected and maintained in service to ensure the security of the supply to the end-user, and to protect the capital investment of the power companies. When single phase grounding fault occurs in high voltage transmission line, secondary arc current and recovery voltage must be suppressed in order to ensure that single phase auto-reclosing operates reliably and successfully. Automatic single phase reclosing is used to clear single-phase-to-ground-faults, which are 80% of the transient faults. In order to have successful fast reclosing, different methods are used to extinguish the arc. One of the common methods is to use a single-phase reactor in the neutral of shunt reactor, when the transmission line is compensated with shunt reactors. In this paper, exact arc modeling is  used for transient simulation of neutral reactor and guidelines for selecting the appropriate amount for the neutral reactor are proposed, then uses MATLAB software to simulate suppression effect about different fault point locations towards an example of 735 KV double ended sources high voltage transmission line. According to the simulation results, suppression effects about different locations are distinct. 
Keywords: High voltage transmission, single phase auto reclosing, secondary arc current, shunt reactor, neutral small reactor.
Title: Study of Secondary Arc Current Suppression Effects under Different Fault Location on Extra High Voltage Line
Author:Shalini Chandel, A. K. Sharma
ISSN 2349-7815
International Journal of Recent Research in Electrical and Electronics Engineering (IJRREEE)
Paper Publications

Abstract: In this paper a comparative performance is analysed of Bipolar and Unipolar inverters using Matlab/ Simulink model for a lagging power factor load. The performance analysis is based upon the harmonic distortion in the output voltage of both the inverters for the same load at different carrier frequencies of the carrier signal and at different modulation index (MI) . SPWM technique is used to reduce the harmonic distortion in the output voltage. By changing the carrier signal frequency, selective order of harmonics can be eliminated and by increasing the modulation index, the % of harmonic component in the output voltage profile can be reduced. There are many inverter topologies but output voltage distortion and efficiency are the two main parameters for the selection of an inverter. In spwm technique two such topologies are Bipolar and Unipolar inverters are presented here. These bridge inverter topologies are fed with constant amplitude pulses with varying duty cycle for each period. The pulses are generated by comparison of two waves – a carrier wave, which is a triangular and a reference or modulating wave which is a sinusoidal wave. The frequency of the output wave is same as the frequency of the reference wave.

Abstract: In this paper, a simulation of SPWM (Unipolar) strategy is presented for Single phase full bridge inverter. The model is simulated in Matlab/Simulink. For different power factor loads the % THD of the output voltage are observed.  The change in modulation index (MI) and the frequency of the carrier signal (f_c) changes the % THD of the output voltage. The width of gate pulses are modulated in order to obtain controlled inverter out voltage and to reduce the harmonic content as well. A comparative study of the % THD of the output voltage for the same load when connected across a conventional inverter and across SPWM fed inverter helps to understand the performance of the inverter. In SPWM inverter, to generate the gate signals, triangle wave is the carrier wave which is compared with the reference sinusoidal wave. The frequency of the output voltage depends on the frequency of the reference wave.

Abstract: Grain storage is the important factor for seasonal production. Grain is an important strategic resource of the country. This article designs Granary Environment Monitoring and Controlling system which is having combination of Embedded system and ZigBee Wireless Sensor Network technology. The design of wireless sensor network using ZigBee which is used for multipoint acquisition and transmission of environment parameters using AVR Processor to the Grain storage manager and transmission of control signals through ARM7 which improves the Scalability and flexibility of grain storage management.

Abstract: In this paper, we are using PLC programmes to control the crane movement. The application of PLC could simplify circuits and make the design easier, safer and more reliable. Earlier in Industry, relays and contactors are adopted to control the crane motion in desired directions. Starting of the cranes and speed control of the crane is realized through convectional starters and resistance series. This kind of design has low reliability, complex operation, high electrical failure rate, power waste and low efficiency .These problems can be rectified by using programmable logic controller.

Abstract: In last few years there is lot of development and attentions in area of blur detection techniques. The Blur detection techniques are very helpful in real life application and are used in image segmentation, image restoration and image enhancement. Blur detection techniques are used to remove the blur from a blurred region of an image which is due to defocus of a camera or motion of an object. In this literature review we represent some techniques of blur detection such as Blind image de-convolution, Low depth of field, Edge sharpness analysis, and Low directional high frequency energy. After studying all these techniques we have found that there are lot of future work is required for the development of perfect and effective blur detection technique.

Abstract: In the induction furnace most concern issue are related to power quality, in the system nonlinear load causes current harmonics and induction furnace cause voltage harmonic.  The harmonics produced in the system they distorts the fundamental sinusoidal waveform so harmonics must be mitigate. One of the best solutions to mitigate harmonics problems is the use of Hybrid filters. Shunt passive filter is to eliminate harmonics currents. Passive filter has some disadvantages mainly related to the filter frequencies they were previously tuned, fixed compensation, resonance can occur because of the interaction between the passive filter and other load, with undesired results. So to overcome this problems development of active filter is required.  Series active filter is suitable for the mitigation of voltage harmonics in this paper we discussed the hybrid scheme having passive filter with tunable element which mitigate current harmonic in between sub order harmonic frequency to particular design order frequency which maintain desired power factor, series active filter with direct control strategies which mitigate voltage harmonic and maintain desired reactive power.

Abstract: It is a framework considering industrial loads for improvement of power factor of industrial load system. Most of loads in industries are inductive in nature and thus having low power factor. Low power factor is highly undesirable and it increases current and also increases losses of active power. This paper discusses how to calculate the correct value of capacitor to improve power factor to overcome above mentioned problems. Because improving power factor will give efficient utilization of electrical power.

Abstract: Computer recognition of sign language is an important research problem for enabling communication with mute people. This project introduces an efficient and fast algorithm for identification of the number of fingers opened in a gesture representing an alphabet of the Binary Sign Language.
The system does not require the hand to be perfectly aligned to the camera. The project uses image processing system to identify, especially English alphabetic sign language used by the mute people to communicate. The basic objective of this project is to develop a computer based intelligent system that will enable mute people significantly to communicate with all other people using their natural hand gestures.
The idea consisted of designing and building up an intelligent system using image processing, machine learning and artificial intelligence concepts to take visual inputs of sign language’s hand gestures and generate easily recognizable form of outputs.
Hence the objective of this project is to develop an intelligent system which can act as a translator between the sign language and the spoken language dynamically and can make the communication between people with mute and normal people both effective and efficient. The system is we are implementing for Binary sign language but it can detect any sign language with prior image processing.