Development of Constant Current Charge Controller for 3KW Wind Turbine

This paper describes the development of constant current charge controller for 3kW wind turbine designing with 48VAC PM alternator. As the wind speed is not constant, the output voltage from the wind turbine is always changing. In the circuit design, the changing voltage is sent to the 48V battery bank (series connection with 12V 200Ah batteries) by using the constant current charging method to extend the battery life. It does not only provide the two-step charging; the first step for the slow charging and the second step for the fast charging, but also use the overheat sensing circuit to prevent the damage of the expensive battery bank. In this work, the controller circuit operates properly switching first stage or second stage alternately depending on the full/low battery voltage. Unfortunately, if the overheating condition appears in the circuit, the cut-out circuit using temperature sensor decides to stop charging. To indicate clearly the battery charging conditions, the LCD display unit using the microcontroller is provided in the circuit design. The current sensing circuit is also added to show the battery charging current on the LCD display through the microcontroller. In this paper, the voltage comparator circuit, the two-step charging circuit, the overheating sensing circuit and the LCD display are described by simulating with Proteus (ISIS

Time reversal Electromagnetic Simulation using FDTD with MATLAB

The Finite Difference Time Domain method (FDTD) uses centre-difference representations of the continuous partial differential equations to create iterative numerical models of wave propagation. Initially developed for electromagnetic problems the technique has potential application in acoustic prediction. In this paper the time reversal electromagnetic simulation has been discussed. That work is based on the sensor management for a room The reversal time for sensor from the different source of transmission could be viewed on the MATLAB command window. This research aims to develop the signal processing of the sensor management within 3 meters around signal source

Development of Constant Current Charge Controller for 3KW Wind Turbine

This paper describes the development of constant current charge controller for 3kW wind turbine designing with 48VAC PM alternator. As the wind speed is not constant, the output voltage from the wind turbine is always changing. In the circuit design, the changing voltage is sent to the 48V battery bank (series connection with 12V 200Ah batteries) by using the constant current charging method to extend the battery life. It does not only provide the two-step charging; the first step for the slow charging and the second step for the fast charging, but also use the overheat sensing circuit to prevent the damage of the expensive battery bank. In this work, the controller circuit operates properly switching first stage or second stage alternately depending on the full/low battery voltage. Unfortunately, if the overheating condition appears in the circuit, the cut-out circuit using temperature sensor decides to stop charging. To indicate clearly the battery charging conditions, the LCD display unit using the microcontroller is provided in the circuit design. The current sensing circuit is also added to show the battery charging current on the LCD display through the microcontroller. In this paper, the voltage comparator circuit, the two-step charging circuit, the overheating sensing circuit and the LCD display are described by simulating with Proteus (ISIS) softwar

Acoustic Echo Cancellation Using Adaptive Least Mean Square Algorithm

In telephony system, the received signal by the loudspeaker, is reverberated through the environment and picked up by the microphone. It is called an echo signal. This is in the form of time delayed and attenuated image of original speech signal, and causes a reduction in the quality of the communication. Adaptive filters are a class of filters that iteratively alter their parameters in order to minimize a difference between a desired output and their output. In the case of acoustic echo, the optimal output is an echoed signal that accurately emulates the unwanted echo signal. This is then used to negate the echo in the return signal. The better the adaptive filter simulates this echo, the more successful the cancellation will be. This paper examines LMS algorithm of adaptive filtering in acoustic echo cancellation system. A discrete signal processing is employed in MATLAB for simulation with acoustic signals

Analysis and Simulation of Sinusoidal PWM Technique for Sine Wave Inverter

A sinusoidal pulse width modulation technique of generating sine wave with minimized harmonics is implemented in this paper. The technique is essentially focused on sinusoidalpulse-width modulation (SPWM) control of H-bridge DC-AC inverter stage connected in series between high voltage DC links (Vs) and output (VO). It also provides the producing of SPWM signals to control the H-bridge inverter driving stage such as single phase or three phases. This technique is mathematically modelled and simulated in Matlab. Finally, the results are verified that the output sine wave is voltage regulated and ripple less. The proposed technique “generation of sinusoidal PWM by comparing a sinusoid with a triangular wave” aims to implement of a voltage regulated sine wave inverter with ripple free and glitch free output sine wave that can be operated electronic devices efficiently

Consistent Replica Selection Mechanism for Cloud Data Storage

Cloud computing is becoming increasinglypopular and cloud storage services attract moreattentions for their high security and availability witha low cost. Cloud storage is expected to become themain force of the future storage market. To achievehigh data availability, cloud storage services rely onreplication. Data replication is a widely usedtechnology in quorum based data center distributedstorage system. In such systems, it is important tochoose a closest set of replicas to service a clientrequest for increasing performance and reliability.Static replica selection would be suboptimal evenover a dedicated infrastructure. Suboptimal replicachoices result in reduced performance as a result ofincreased response latency. In this paper, aconsistent replica selection mechanism is proposed toautomatically select number of consistent replicas bysearching nearest replicas and selecting consistentreplicas depends on current time, nearest arrivaltime, read/write latency and version for each readrequest. This mechanism tends to achieve theperformance of client requests for cloud services byreducing latency cost

Analysis of phase Lead compensation design for Hot-Ingot Robot control system using

The paper describes the result comparisons that were developed for the phase lead compensator design using MATLAB. The MATLAB m-files that use the implementation of classical experiments are described. The Root locus analysis for stability of Hot-Ingot Robot Control System has been analyzed. The Hot-Ingot Robot Control System can be designed to gain insight into a variety of concepts, including stabilization of unstable control systems, Root locus analysis. The analysis has resulted in a number of important conclusions for the design of a new generation of control support systems

GPS and Microcontroller Interfacing for Vehicle Warning System

The global positioning system (GPS) has solidified its presence as a dependable means of navigation by providing absolute positioning in various applications. Coordination of vehicles in high-density traffic increases the efficiency of transportation infrastructure usage while improving safety standards. Vehicle warning system’s design for highway and other traffic zone monitors its own precise location using GPS receiver, and alerts when pre recorded blackspots near. In the first stage, latitude and longitude information are extracted from NMEA messages of GPS receiver to display on LCD. The second stage involves the comparison of the current position with stored blackspots location and then alerts. This paper describes an interfacing between GPS and Microcontroller as a first stage of this system. It utilized currently available technology to interface with the vehicle computer and the global positioning system device

Development of Altitude Control System for Autonomous Flight Vehicle

The purpose of doing this research is to develop and implement altitude control system for holding of aerial vehicle. This paper emphasizes on the longitudinal stability control system. Experimental autonomous flight vehicle developed by Tamkang University is used as the application airframe as it gives coefficients to get the very accurate model of aircraft flight behaviour. An altitude hold control structure is constructed classical designs. The structure contains two control loops. The inner loop is for altitude rate regulation. In this control loop, the combination of altitude rate and pitch angle are used as the feedback signals. The simulation results of the inner loop are used to design the outer altitude control loop. The inner control loop for this research work is considered in this paper