Relay weld diagnostic device

摘要

In relay weld diagnostic device, a threshold value determination unit (104) determines a threshold value on the basis of a resistance value that is set for each of a P-pole-side resistor (24) and an N-pole-side resistor (23) provided to charging equipment. A peak value measuring unit (110) measures the peak value of a voltage supplied to a voltage line by an alternating-current signal output circuit (112). A comparison diagnosis unit (111) assesses the state of a relay (14) on the P-pole side and a relay (15) on the N-pole side by comparing the peak value and the threshold value, and makes a diagnosis as to whether the relays (14), (15) are welded on the basis of the assessed state of the relays (14), (15) and the state in which the relays (14), (15) are controlled.

主权项

1. A relay welding diagnostic apparatus configured to be operated by switching between a relay diagnosis mode and a leakage detection mode, the relay diagnosis mode being configured to determine whether relays which are respectively provided on a P electrode side and an N electrode side of a voltage line connecting a charging facility and a battery together are welded, the leakage detection mode being configured to detect a leakage in the voltage line, the relay welding diagnostic apparatus comprising:
an AC signal output circuit that supplies a predetermined AC voltage to the voltage line, the AC signal output circuit being provided separately from the charging facility; a peak value measurement section that measures a peak value of the voltage supplied to the voltage line from the AC signal output circuit; and a comparison diagnosis section that compares the peak value with a threshold value, wherein in the leakage detection mode, the comparison diagnosis section detects a leakage by comparing the peak value with a threshold value for the leakage detection mode, and in the relay diagnosis mode, the comparison diagnosis section determines a state of the relay by comparing the peak value with a threshold value for the relay diagnosis mode that is different from the threshold value for the leakage detection mode, and determines whether the relay is welded on a basis of the state of the relay thus determined and a state set to the relay.