Browse Prior Art Database

Bridge Commutate Circuit for Silicon Controlled Rectifier

IP.com Disclosure Number: IPCOM000080791D
Original Publication Date: 1974-Feb-01
Included in the Prior Art Database: 2005-Feb-27
Document File: 2 page(s) / 28K

Publishing Venue

IBM

Related People

Felton, BC: AUTHOR

Abstract

Silicon-controlled rectifier (SCR) 2 supplies current from a point +V to a load 3 that is connected to a node 4, by a filter that includes a capacitor 5 and an inductor 6. The other components in the drawing cooperate to turn off SCR 2, and SCR 2 is switched on and off to provide a selected average voltage at node 4.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 81% of the total text.

Page 1 of 2

Bridge Commutate Circuit for Silicon Controlled Rectifier

Silicon-controlled rectifier (SCR) 2 supplies current from a point +V to a load 3 that is connected to a node 4, by a filter that includes a capacitor 5 and an inductor 6. The other components in the drawing cooperate to turn off SCR 2, and SCR 2 is switched on and off to provide a selected average voltage at node
4.

Suppose that SCR 2 is on and that capacitor 7 is charged -,+ as shown in the drawing. To turn off SCR 2, SCR's 8 and 9 are turned on. This operation connects capacitor 7 and an inductive winding 10 in series between node 4 and point +V; as the current in this circuit rises, the , current in SCR 2 falls and SCR 2 turns off. The combination of capacitor 7 and winding 10 causes the current in this circuit to rise to a peak value and then to fall. SCR 2 turns off at the point in time when capacitor 7 supplies the entire load current.

As the capacitor current rises above the value of the load current, a diode 11 turns on to conduct the excess current. Capacitor 7 continues to supply current to the load until it has become charged +,- to a sufficient value that a diode 13 turns on, to supply the load current from potential point -V and to prevent capacitor 7 from being charged further. At this point in the cycle, energy is supplied to the load by inductors 6 and 10.

At a selected time, SCR 2 is again turned on and the current in SCR 2 rises as the current in winding 10 falls. Capacitor 7 is charged...