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SMPT Lecture Series: Lecture 2

posted Nov 8, 2012, 5:48 AM by smpt cob   [ updated Nov 12, 2012, 1:56 PM ]

November 20th

Library, Classroom A, 2 p.m.


Implementation of a Low-Voltage Single-Phase Supply to Generate a Three-Phase System Using Operational Amplifiers


Leonard Edgecombe, Neko Hield, Sheridan Murphy


The purpose of this project was to design and produce an inexpensive, low voltage, three- phase power system using a single-phase supply in order to provide technology students with a safer way to study single and three-phase signals by producing voltages with relatively low amplitudes.  It was intended that each phase would have a voltage of 10 Vp-p and each is 120 degrees out of phase of each other. This was done using conventional UA741 operational amplifiers, resistors and capacitors. These components were used to construct the three stages needed for the project which consisted of a square wave function generator, two second order low-pass active filters, and a mixer circuit. With the completion of the project, three sine waves were produced in which the Phase A voltage was 10.1 Vp-p and its phase 0 degrees, Phase B voltage was 10.0 Vp-p and its phase -119.2 degrees in reference to phase A, and Phase C voltage was 9.92 Vp-p and its phase 122.7 degrees in reference to phase A.