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. 07, 2013
Filed:
Aug. 06, 2010
Seiji Funaba, Hitachinaka, JP;
Yasuo Noto, Hitachinaka, JP;
Masashige Tsuji, Hitachinaka, JP;
Hitachi Automotive Systems, Ltd., Hitachinaka-shi, JP;
Abstract
A discharge circuit for a DC power supply smoothing capacitor that is used in a power conversion device that supplies DC power via a switch to the DC power supply smoothing capacitor and an inverter, includes; a resistor that discharges charge in the capacitor; a switch connected in series with the resistor, that either passes or intercepts discharge current flowing from the capacitor to the resistor; a measurement circuit that measures a terminal voltage of the capacitor; and a control circuit that controls continuity and discontinuity of the switch; wherein the control circuit, after having made the switch continuous and starting discharge of the capacitor by the resistor, if a terminal voltage of the capacitor as measured by the measurement circuit exceeds a voltage decrease characteristic set in advance, makes the switch discontinuous and stops discharge by the resistor.