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:
Nov. 06, 2007
Filed:
Jul. 10, 2006
Tsuyoshi Morita, Zama, JP;
Shinsuke Nakazawa, Yokohama, JP;
Tsuyoshi Morita, Zama, JP;
Shinsuke Nakazawa, Yokohama, JP;
Nissan Motor Co., Ltd., Yokohama-shi, Kanagawa, JP;
Abstract
A ground fault detector and detection method for a vehicle that can determine the cause of the occurrence of a ground fault after detecting the presence of the ground fault. The output terminal of a high-voltage battery is connected to one side of a coupling capacitor. In operation, a pulse signal is applied to a measurement point on the other side of the coupling capacitor, and the voltage generated at that point is detected. Whether the high-voltage battery or the electrical equipment units are grounded is determined. To determine the cause of the ground fault, the oscillation frequency of the square-wave pulse signal is changed and applied to the measurement point. From the change in voltage amplitude detected, it is determined whether the cause of the ground fault is a resistive or a capacitive ground fault, according to the change in the impedance of the battery or the units.