Vehicle ground fault detection apparatus
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.
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 a process of detecting 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 3 , wherein the battery for vehicle driving is used as a power supply to charge the coupling capacitor.
5. The vehicle ground fault detection apparatus of claim 4 , wherein a voltage detection resistor is used in a circuit to discharge the coupling capacitor.
6. The vehicle ground fault detection apparatus of claim 4 , wherein the coupling capacitor is charged and discharged while an ignition is off.
7. The vehicle ground fault detection apparatus of claim 3 , wherein a voltage detection resistor is used in a circuit to discharge the coupling capacitor.
8. The vehicle ground fault detection apparatus of claim 3 , wherein the coupling capacitor is charged and discharged while an ignition is off.
9. 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.
10. The vehicle ground fault detection apparatus of claim 9 , wherein a voltage detection resistor is used in a circuit to discharge the coupling capacitor.
11. The vehicle ground fault detection apparatus of claim 9 , wherein the coupling capacitor is charged and discharged while an ignition is off.
12. The vehicle ground fault detection apparatus of claim 2 , wherein a voltage detection resistor is used in a circuit to discharge the coupling capacitor.
13. The vehicle ground fault detection apparatus of claim 2 , wherein the coupling capacitor is charged and discharged while an ignition is off.
14. 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.
15. The vehicle ground fault detection apparatus of claim 14 , wherein a voltage detection resistor is used in a circuit to discharge the coupling capacitor.
16. The vehicle ground fault detection apparatus of claim 14 , wherein the coupling capacitor is charged and discharged while an ignition is off.
17. The vehicle ground fault detection apparatus of claim 1 , wherein a voltage detection resistor is used in a circuit to discharge the coupling capacitor.
18. The vehicle ground fault detection apparatus of claim 17 , wherein the coupling capacitor is charged and discharged while an ignition is off.
19. The vehicle ground fault detection apparatus of claim 1 , wherein the coupling capacitor is charged and discharged while an ignition is off.
20. The vehicle ground fault detection apparatus of claim 1 , wherein the coupling capacitor comprises a plurality of aluminum electrolytic capacitors.