LEAK DETECTOR OF ELECTRIC VEHICLE

摘要

PROBLEM TO BE SOLVED: To make always safely detectable a leak by impressing alternating current signal between a vehicle body and a high voltage battery pack and obtaining the resistance component of admittance from the relation between amplitude and phase of the signal voltage and current. SOLUTION: An alternating current signal is generated by an alternating signal source 1, a leak detector circuit and a battery pack 3-ac are isolated through a capacitor 2 and the alternating current signal is sent to the battery pack 3-ac including a leak admittance 3b-2 between a high voltage assembly battery 3a and a vehicle body. A phase discrimination means 4 converts the phase difference between an alternating current (i) and alternating voltage (v) of the alternating signal source 1 into a voltage Vϕ. An admittance detection means 5 outputs a voltage Vyleak corresponding to leak admittance form the alternating current (i) and the alternating voltage (v). A leak judgment means 6 obtains the real part of the admittance, that is, a resistance component of the leak from the voltage Vϕand the absolute value of the admittance to compare with the reference value of the resistance component with a comparison means 6b and the existence of leak can be judged.