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:
Jun. 02, 1992
Filed:
Apr. 03, 1991
Gang Liu, Detroit, MI (US);
Michael P Polis, Grosse Pointe Park, MI (US);
Beijing Wang, Detroit, MI (US);
Wayne State University, Detroit, MI (US);
Abstract
A solid-state power transformer circuit is provided for converting the positive and negative periods from an AC input signal having a predetermined frequency and applied to an input of the circuit into a high frequency signal and, subsequently, converting the high frequency signal into a regulated output signal at an output of the circuit. A plurality of electronic optically-coupled switches are utilized for chopping the AC input signal at a chopping frequency. The switches are controlled by the oscillator of an integrated circuit to adjust the duty cycle of the switches. A filter, in the form of a pair of capacitors, is connected between the input and output to suppress the high-frequency voltage harmonics produced during chopping. The capacitors, in combination with other capacitive and resistive elements of the circuit provide a total separation impedance between the input and output of the circuit to electrically isolate the output from the input. The integrated circuit also includes a switch and a controller which controls the switch and oscillator by monitoring the output signal and comparing the output signal with a reference signal so that the oscillator produces a control signal for controlling the duty cycle of the optically-coupled switches so that the output signal is regulated.