Electronic and Communication - Engineering

Abstract : This work deals with developing suitable attitude control algorithm for a small low Earth orbit satellite of minimum cost and complexity. The proposed attitude control system deals with a combination of passive and active control methods. Passive control is represented by boom deployment to ensure Earth pointing with accuracy (of _ 50 ). Active control method is accomplished by the use of a set of mutually perpendicular coils called magnetorquer mounted on the principal axes of the spacecraft.

Abstract : Wide range temperature monitoring and annunciation systems are implemented in many industrial applications and the present work is intended to develop a modern and easy-to-install temperature monitoring system that serves monitoring and annunciation of several nodes. The proposed system uses type-k thermocouples as primary sensing element; the output voltage from the thermocouple is amplified using suitable thermocouple amplifier circuits. The system is intended to measure temperatures in the range from 0 to 1250 °C at two different measuring points.

Abstract : In recent years modulation techniques techniques have been introduced into power semiconductor switching devices have proved to be suitable elements for achieving the required modulation processes. Due to the development of these devices, modulation find widespread application in the power frequency conversion and power control. In the present work an attempt is made to use a frequency modulation of discrete form as a technique to development a frequency changer which may compete with the conventional power frequency changer.