Vehicle ground fault detection apparatus

Patent metadata

Field	Value
Publication number	US-2017197508-A1
Application number	US-201515313996-A
Country	US
Kind code	A1
Filing date	Apr 3, 2015
Priority date	May 26, 2014
Publication date	Jul 13, 2017
Grant date	—

Abstract

This vehicle ground fault detection apparatus maintains a high level of insulation in an aluminum electrolytic capacitor to improve long-term reliability. This vehicle ground fault detection apparatus ( 10 ) detects a ground fault of a DC power supply by connecting the positive terminal or the negative terminal of a high-voltage power supply to one terminal of a coupling capacitor ( 15 ) provided with aluminum electrolytic capacitors (C 1, C 2, C 3 ), applying a square-wave pulse signal to a measurement point at the other terminal of the coupling capacitor, and detecting a voltage signal generated at the measurement point. The vehicle ground fault detection apparatus ( 10 ) includes a charger and discharger (CPU 13 ) that charges and discharges the coupling capacitor when a ground fault of the DC power supply is not being detected.

First claim

1 . A vehicle ground fault detection apparatus for detecting a ground fault of a DC power supply by connecting a positive terminal or a negative terminal of a high-voltage power supply to one terminal of a coupling capacitor provided with an aluminum electrolytic capacitor, applying a square-wave pulse signal to a measurement point at the other terminal of the coupling capacitor, and detecting a voltage signal generated at the measurement point, the vehicle ground fault detection apparatus comprising:
a charger and discharger configured to charge and discharge the coupling capacitor when processing to detect a ground fault of the DC power supply is not being performed.

2 . The vehicle ground fault detection apparatus of claim 1 , further comprising a voltage measurement unit configured to measure a voltage of the coupling capacitor after charging.

3 . The vehicle ground fault detection apparatus of claim 2 , wherein the voltage measurement unit is further configured to measure a voltage of a battery for vehicle driving.

4 . The vehicle ground fault detection apparatus of claim 1 , wherein a battery for vehicle driving is used as a power supply to charge the coupling capacitor.

5 . The vehicle ground fault detection apparatus of claim 1 , wherein a voltage detection resistor is used in a circuit to discharge the coupling capacitor.

6 . The vehicle ground fault detection apparatus of claim 1 , wherein the coupling capacitor is charged and discharged while the ignition is off.

7 . The vehicle ground fault detection apparatus of claim 1 , wherein the coupling capacitor comprises a plurality of aluminum electrolytic capacitors.

8 . The vehicle ground fault detection apparatus of claim 2 , wherein a battery for vehicle driving is used as a power supply to charge the coupling capacitor.

9 . The vehicle ground fault detection apparatus of claim 3 , wherein the battery for vehicle driving is used as a power supply to charge the coupling capacitor.

10 . The vehicle ground fault detection apparatus of claim 2 , wherein a voltage detection resistor is used in a circuit to discharge the coupling capacitor.

11 . The vehicle ground fault detection apparatus of claim 3 , wherein a voltage detection resistor is used in a circuit to discharge the coupling capacitor.

12 . The vehicle ground fault detection apparatus of claim 4 , wherein a voltage detection resistor is used in a circuit to discharge the coupling capacitor.

13 . The vehicle ground fault detection apparatus of claim 8 , wherein a voltage detection resistor is used in a circuit to discharge the coupling capacitor.

14 . The vehicle ground fault detection apparatus of claim 9 , wherein a voltage detection resistor is used in a circuit to discharge the coupling capacitor.

15 . The vehicle ground fault detection apparatus of claim 2 , wherein the coupling capacitor is charged and discharged while the ignition is off.

16 . The vehicle ground fault detection apparatus of claim 3 , wherein the coupling capacitor is charged and discharged while the ignition is off.

17 . The vehicle ground fault detection apparatus of claim 4 , wherein the coupling capacitor is charged and discharged while the ignition is off.

18 . The vehicle ground fault detection apparatus of claim 5 , wherein the coupling capacitor is charged and discharged while the ignition is off.

19 . The vehicle ground fault detection apparatus of claim 8 , wherein the coupling capacitor is charged and discharged while the ignition is off.

20 . The vehicle ground fault detection apparatus of claim 9 , wherein the coupling capacitor is charged and discharged while the ignition is off.

Assignees

• Calsonic Kansei Corp

Inventors

• Kobayashi Yasuhiro

Classifications

• B60L3/0069

  relating to the isolation, e.g. ground fault or leak current · CPC title

• G01R31/006

  on road vehicles, e.g. automobiles or trucks (testing of ignition installations peculiar to internal combustion engines F02P17/00) · CPC title

• G01R31/3835

  involving only voltage measurements · CPC title

• G01R31/025

  Physics · mapped topic

• B60L3/0046 Primary

  relating to electric energy storage systems, e.g. batteries or capacitors · CPC title