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. 01, 1979
Filed:
Mar. 27, 1978
Richard K Davis, Salem, VA (US);
General Electric Company, New York, NY (US);
Abstract
In an adaptive type of control for precipitators, the current reference ramp signal is compared with a precipitator current signal to produce a phase reference signal which is combined with sawtooth waves to produce a first train of pulses. In a spark detector, signals proportional to electrode potential are differentiated, and the differentiated output is integrated. The integrator output, if in excess of a reference potential, triggers a spark pulse of predetermined width and amplitude. The spark pulse, in addition to causing a predetermined small set back of the ramp signal, is integrated to produce a turn-off and recovery signal having a rapid excursion and subsequent slower return excursion of adjustable slope. The latter signal is combined with the sawtooth waves to produce a second train of pulses commencing after a predetermined turn-off interval and increasing in width at a predetermined recovery rate. Both trains of pulses are added to produce enabling signals for controlling the SCR's in the precipitator input circuit. Arc signals produced by an arc detector cause additional downward ramping of the ramp signal to minimize electrode current during arcing.