The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 06, 1997
Filed:
May. 19, 1995
Vadim Lubomirsky, Penfield, NY (US);
Jeff C Sellers, Palmyra, NY (US);
ENI, A Division of Astec America, Inc., Rochester, NY (US);
Abstract
A soft start circuit for a high-power module permits trickle-charging of the capacitor bank prior to power switch actuation, and avoids large current surges or inrush at power up. Positive temperature coefficient thermistor devices, or PTCs are place in shunt across the switch elements or poles of the actuator or other power switch. In a power module that is powered by three-phase AC, the three power conductors are coupled through a three-pole contactor to AC inputs of a polyphase rectifier bridge, which has DC outputs coupled to the capacitor bank and to a load device, such as a high-power RF amplifier. The PTCs are connected, one per pole, in shunt across each pole of the contactor. Alternatively, metallized film capacitors can be employed in lieu of the PTCs.