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Determination of Remotely Located Voltage Phase Angles

IP.com Disclosure Number: IPCOM000074629D
Original Publication Date: 1971-May-01
Included in the Prior Art Database: 2005-Feb-23
Document File: 2 page(s) / 37K

Publishing Venue

IBM

Related People

Shortie, JW: AUTHOR [+2]

Abstract

It is often quite difficult to determine the relative phase relationships of voltages at generating plant busses, since the busses are frequently remotely located with respect to one another.

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Determination of Remotely Located Voltage Phase Angles

It is often quite difficult to determine the relative phase relationships of voltages at generating plant busses, since the busses are frequently remotely located with respect to one another.

Phase relationships of all voltages at, for instance, generator busses of a dispersed power system may be measured for control purposes by the illustrated system. The precision oscillator provides a continuous source of clock pulses to the accumulator counter which does not provide an output until it has received an "on-time" pulse from the on-time receiver to start its accumulating function. When the sensor applies the voltage sine-wave to the zero-crossing detector, and the voltage sine-wave crosses zero, the zero-crossing detector produces a "transfer" signal to transfer the current value in the accumulator counter to buffer register No. 1. The next zero-crossing is detected by zero-crossing detector to produce a second transfer signal. This second transfer signal causes a transfer of the now current value of the accumulator counter to buffer register No. 2. Values stored in buffer registers No. 1 and No. 2 are read into the terminal unit and transmitted over communication links to a computer. The computer determines the period of the voltage sine-wave T3 by subtraction of T1 from T2. The voltage phase relative to the "on-time" pulse is computed as T1 over T2(360 degrees) = phi(RT). The voltage phase of any buss relat...