5.Asynchronous Systems

The past decade has seen tremendous advancement in the design of computer systems. Every year the speed and amount of integration of the processors is increasing exponentially, as per one of the most famous technology predictions of our times: known as Moore’s Law (Dr. Gordon Moore, Cofounder of Intel).
The amount of power dissipation in a chip is also increasing rapidly. Within a decade, the power dissipation in processors as per the current technology will reach to the maximum controllable limits. Reduced power consumption is also very important as we embed computing devices in portable electronic devices. Clockless or asynchronous design methodology is one solution, which can give better performance with reduced power consumption compared to current synchronized to a global clock. So there is no dynamic power consumption. Also, they give "average-case" performance instead of "worst case" performance as in synchronous systems. Thus, asynchronous systems are faster than their synchronous counter parts. The current synchronous design techniques won't be able give optimum results for future processors. A synchronous systems with their improved performance and reduced power consumption are the best alternative currently available for such systems involving intensive computations, portable compact systems etc. This seminar report attempts to bring out the concept of clockless computing and their merits over current computing techniques, which equip it to replace current techniques in near future.

4) ANN Based Power System Restoration

Power System Restoration (PSR) has been a subject of study for many years. In recent years many techniques were proposed to solve the limitations of predetermined restoration guidelines and procedures used by a majority of system operators to restore a system following the occurrence of a wide area disturbance. This paper discusses limitations encountered in some currently used PSR techniques and a proposed improvement based on Artificial Neural Networks (ANNs). This proposed scheme has been tested on a 162-bus transmission system and compared with a breadth search transmission system. The results indicate that, this is a feasible option that should be considered for real time applications.
Artificial Neural Networks (ANNs) are computational techniques that try to obtain a performance similar to that of human’s performance when solving problems. The building block of ANN is Artificial Neuron, which has got structural & functional similarities with biological neurons. ANN is also an efficient alternative for problem solutions where it is possible to obtain data describing the problem behavior, but a mathematical description of the process is impossible. The proposed restoration scheme is composed of several Island Restoration Schemes (IRS). Each IRS is responsible for the development of an Island Restoration Plan when the power system is recovering from a wide area disturbance

3) Advancements In Inverter Technology For Industrial Applications

An Inverter is simply an electronic device that converts low voltage DC battery power 230 volts AC (Alternating Current) electrical power. They are used in applications ranging from microwaves laptops to satellite systems X-Ray machines etc. Most industrial applications require high frequency high voltage power supply. These increased power requirements have lead to significant development in inverted technology.
Significant improvements have been made to the traditional pulse width modulations (PWM) Inverters to make power distribution system more efficient and more suitable to reactive power (var) compensation and harmonic filtering. This includes using multilevel inverters, zero current switching and other power switching devises. Space application involves high power (hundreds of kilowatts to megawatts) systems. Large power conditioning mass reductions are required to enable this megawatt power System. Therefore inverter design for space applications represents the state - of - the- art in power conditioning technology. Different features such as design parameters, output a characteristics, switching components etc of these inverters used in space application are discussed in the II part of the paper.

2) Adaptive Piezoelectric energy harvesting circuit

This paper describes an approach to harvesting electrical energy from a mechanically excited piezoelectric element. A vibrating piezoelectric device differs from a typical electrical power source in that it has a capacitive rather than inductive source impedance, and may be driven by mechanical vibrations of varying amplitude. An analytical expression for the optimal power flow from a rectified piezoelectric device is derived, and an “energy harvesting “ circuit is proposed which can achieve this optimal power flow. The harvesting circuit consists of an ac-dc rectifier with an output capacitor, an electrochemical battery, and a switch-mode dc-dc converter that controls the energy flow into the battery. An adaptive control technique for the dc-dc converter is used to continuously implement the optimal power transfer theory and maximize the power stored by the battery. Experimental result reveal that the use of the adaptive dc-dc converter increases power transfer by over 400% as compared to when the dc-dc converter is not used.