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Regulators With Feedback Control

IP.com Disclosure Number: IPCOM000085962D
Original Publication Date: 1976-Jun-01
Included in the Prior Art Database: 2005-Mar-03
Document File: 2 page(s) / 34K

Publishing Venue

IBM

Related People

Herrell, DJ: AUTHOR [+2]

Abstract

In a known parallel powering scheme the voltage regulator is provided by a string of n Josephson tunneling gates, each switching to the gap voltage, Vg, for total regulator voltage of nVg. Due to variations in the maximum superconducting current, I(m), of each junction and to the delay between junctions, one junction will reach its I(m) first, and switch to the voltage state causing a drop in gate current, I(g), through the regulator string (Fig. A). Until current once again builds up in the regulator string, the other junctions will not switch to V not = 0. Under these conditions, a well-defined output voltage is not guaranteed.

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Regulators With Feedback Control

In a known parallel powering scheme the voltage regulator is provided by a string of n Josephson tunneling gates, each switching to the gap voltage, Vg, for total regulator voltage of nVg.

Due to variations in the maximum superconducting current, I(m), of each junction and to the delay between junctions, one junction will reach its I(m) first, and switch to the voltage state causing a drop in gate current, I(g), through the regulator string (Fig. A). Until current once again builds up in the regulator string, the other junctions will not switch to V not = 0. Under these conditions, a well-defined output voltage is not guaranteed.

The use of feedback control to correct this problem can be used as follows: current, I(L), in the load transmission line is directed, as a control line, back over the string of regulator junctions (Fig. B). As the proportion of regulator junctions switch to V not = 0 state, the load current will reduce the effective I(max) of the still unswitched regulator junctions. The I(max) should be reduced to below the resultant current flowing in the regulators following a partial switch, and will thus ensure that all unswitched regulator junctions now switch. A well-defined output voltage of n{2 delta/e} will result with a final load current: I(L) = n 2 delta over eR(L). (1).

The control current feedback should be designed to ensure: bp >= 1 + n over I(L) {delta I(m)(0) - delta I(s)) (2) where: b = slope of regula...