Electrical and Electronics

The ever increasing growth in the market of PM machines has necessitated the need for a careful simulation of the performance of the very important tools capable of taking electrical study to a higher level. Simulations have helped the process of developing new systems by reducing cost and time. Simulation tools have the capabilities of performing dynamic simulations of electric machines in a graphic environment so as to ease the development of new systems. This paper investigates the performance of permanent magnet generator, with the aid of MATLAB/SIMULINK®; a powerful software mathematical tool, for high performance numerical computation. A 230V, 4hp, 2-Pole permanent magnet generator is simulated. The permanent magnets are conspicuously embedded in its rotor. The objective of the paper is to explore the response of the torque components during various operating conditions. Simulation results showed that damper resistances and rotor inertia constant affects the start-up transients of the permanent magnet generator. That is, when the damper resistance and rotor inertia constant were increased there was an increase in the start-up transients. Equally, the responses to step changes in mechanical loading were also observed.

This project proposes a real time fuzzy assisted particle swarm optimization (PSO) based energy management strategy for the multi-source electric vehicles (EVs). In pure EVs the major on-board energy source is the battery which is generally accompanied with other sources such as fuel cell (FC), ultra capacitor (UC) to improve its life time. The energy management algorithm which is formulated as an optimization problem in this project provides optimum sharing of energy sources to meet the vehicle load requirement at every instant without any prior knowledge about the driving profile. The proposed algorithm is simple, efficient and can be easily implemented in a low cost embedded system.

The ultimate goal of the deployment of any voice-centric application is to provide a natural way of human-machine interaction in end-to-end communication and majority of the voice-centric applications in today’s world are promising the same. In this scenario, it is essential to investigate the performance of Speech-Enabled IVR (SEIVR) under the effect of different narrowband codecs. In this paper, the performance of SEIVR has been analyzed by utilizing an ASR engine and speech codecs. SPHNIX-3 has been used as the ASR engine which is CMU’s ASR toolkit for speech recognition and executable files of various narrowband codec are generated with the help of source code and it is taken from standard organizations such as ITU-T, ETSI and ISO/IEC. The results of this paper are completely based on the speech data from TIMIT speech database. The major work done in this paper is to prove that the recognition accuracy of SEIVR increases when there is an increase in Gaussian mixture from Context-Independent (CI) to Context-Dependent (CD) under the influence of various narrow band codecs.

This paper evaluates the benefits of operating an electric distribution network in a security-constrained optimal power flow (SCOPF) in order to mitigate against possible blackout in an N-1 contingency. A 16-bus UKGDS network was used for the analysis. An SCOPF was performed on the network by introducing N-1 line contingency to the network and this resulted to constraints violations. The infeasibility in the solution occurred due to the radial nature of the network. The operation of SCOPF is realized in a mesh network system, which was done by connecting branches between bus 5-7 and bus 12-16 to the network. The system was simulated to operate in SCOPF and N-1 line contingency was inserted to the network to test for constraint violation/ feasibility of the system. This resulted in feasible solution in all the line contingencies with no constraint violation.

Cryptography circuits for portable electronic devices provide user authentication and secure data communication. These circuits should, in general, occupy small chip area, consume low power, handle several cryptography algorithms, and provide acceptable performance. This paper presents the simulation and synthesis of three standard cryptography algorithms on a universal architecture. The cryptography processor implements both private key and public key algorithms and meets the power and performance specifications. The mentor graphics modelsim tool is used for design and simulation and also Synopsys Design Compiler tool is used for synthesis. TSMC 65nm library is used for the synthesis.

In this paper experimentally investigated error-free underwater wireless optical communication (UWOC) system over 7m path in laboratory tap water with up to 46.808dB and BER less than 2.487×10-6. The laser diode source of wavelength 532 nm with 50mW has modulated by intensity modulation/direct detection (IM/DD) technique, BER and S/N have inspected in an underwater optical wireless communication channel with five different water channels types. These are tap water, different concentration of Maalox (Mg(OH)2 and Al(OH)3) in order to obtain high turbid water and salt with Maalox. The analysis of BER has achieved for pulse width modulation (PWM) to transmit a text from optical transmitter to receiver. Results shows that salt and Maalox content decreases the received power, S/N and increase in BER. Also, that 532nm wavelength is the suitable choice for a clear water channel.

We study jitter control in networks with guaranteed quality of service (QoS) from the competitive analysis (as mentioned in [1]) point of view. we analyze on-line algorithms for single jitter regulator that control jitter and compare their performance to the best possible by an off-line algorithm as proposed in [1]. For delay jitter, where the goal is to minimize the difference between delay times of different packets, we show that a simple on-line algorithm using a buffer of B slots guarantees the same delay jitter as the best off-line algorithm using buffer space B/2. We prove that the guarantees made by our (proposed in [1]) on-line algorithm hold, even for simple distributed implementations, where the total buffer space is distributed along the path of the connection, provided that the input stream satisfies a certain simple property. The significance of the results is that it proves the on-line algorithm to be the best possible algorithm to reduce delay jitter for a given buffer size B. The main argue is even if both the distributed and non distributed algorithms get same jitter which one has more advantage. We focused on the advantages of distributing the buffers. The algorithm in its original form is applicable only to a fixed number of packets. We extend the results to a more practical model in which we compare off-line algorithm with n inputs and on-line algorithms with n1 (>n) inputs.

One of the major problems in power system is the occurrence of disturbances that affect the quality of electricity supply. Fault location detection is therefore the key to reliable operation of power equipments and satisfactory service delivery with minimum interruption. This need has given rise to fault location techniques so that the effects of fault can be mitigated with appropriate corrective measures. This paper, thus, presents two algorithmic approaches towards fault location detection with and without using transmission line parameters. A comparison between these techniques, that is the impedance-based method and travelling wave-based method was done to ascertain their degree of efficacy in estimating the distance of various faults at different locations on the transmission line model. The modelling and simulations were done using Simulink and the algorithms of both methods were written using MATLAB codes. Lower the value of percentage error, better the accuracy of algorithm.

The wide range of transmission medium is covered by the wireless sensor network. Due to its increasing popularity many research are done to increase its energy level for effective transmission. The earliest approach in transferring packets with prior processing is more efficient which used the concept of Ant Colony Optimisation approach to obtain the chain.  This existing Power Energy Gathering with Ant colony approach (PEG-ACO) is efficient in minimising transmission distance but there is no mechanism to find out interrupts in transmission, packet loss due to node failure. This paper proposes routing algorithm artificial bee colony approach which optimises the energy level in nodes. The chain is obtained by clustering the nodes with multiple mobile sinks using Artificial Bee Colony (PEG-ABC) concept in order to avoid node failure and packet lost. The load among the nodes is balanced for effective transmission of packets with less energy consumption.

To exploit limited spectrum efficiently CR technology allows unlicensed users to access licensed spectrum bands. Since licensed users have priorities to use the bands, the unlicensed users need to continuously monitor the licensed user’s activities to avoid interference and collisions. To obtain reliable results of the licensed user’s activities is the main task for spectrum sensing. Based on the sensing results the unlicensed users should adapt their transmit powers and access strategies to protect the licensed communications. This paper presents a new spectrum sensing method based on Time-Frequency Analysis. Several realistic signals are taken under different noisy conditions for analysis using Frequency Slice Wavelet Transform (FSWT) to verify its superiority in spectrum sensing.