Browse Prior Art Database

Fault Isolation in Parallel Power Supplies

IP.com Disclosure Number: IPCOM000119774D
Original Publication Date: 1991-Feb-01
Included in the Prior Art Database: 2005-Apr-02
Document File: 1 page(s) / 55K

Publishing Venue

IBM

Related People

Egan, PK: AUTHOR [+2]

Abstract

Described is a method to correctly identify a failing power supply among a group (two or more) of power supplies connected in parallel.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 69% of the total text.

Fault Isolation in Parallel Power Supplies

      Described is a method to correctly identify a failing power
supply among a group (two or more) of power supplies connected in
parallel.

      Switching power supplies using current mode control circuitry
are utilized in a Master-Slave arrangement. Although all supplies may
be equipped with identical circuitry, one is designated a Master via
the hookup wiring, and it provides the amplified error voltage signal
to the other Slave supplies.  This accomplishes two things:  First,
any drift of the common output voltage can be blamed on the Master
supply since only its voltage reference and error amplifier are used
to determine the common output voltage. Second, the Master's error
voltage signal can be compared to the Slave supply's actual output
current to determine if the Slave is contributing its proper share of
the combined output power.  Using these concepts along with an input
voltage sensor, an output current sensor, and reporting only the
first fault detected, makes it possible to diagnose a power fault in
a multiple parallel power supply system.  Any fault can be identified
to the primary power source, output load, or a particular power
supply among the parallel units.

      Refer to the figure which shows an implementation of the
concepts.  The master error amplifier output is connected to the
slave error signal inputs of all the parallel supplies, and this
signal is utilized as the reference input to a...