JAJU528B August 2022 – January 2023 OPA388-Q1
An error condition is created at ¾ HV battery voltage to chassis ground. To understand the behavior of error conditions, measurements were performed at different battery voltages.
Battery voltage = 400 V, isolation error = 300 V | |
CH1: ISO_POS CH2: ISO_NEG CH3: RELAY_NEG CH4: RELAY_POS | |
Battery voltage = 450 V, isolation error = 337.5 V | |
CH1: ISO_POS CH2: ISO_NEG CH3: RELAY_NEG CH4: RELAY_POS | |
HV BATTERY VOLTAGE (SUPPLIED AND MEASURED) | MEASURED REFERENCE VOLTAGE | MEASURED PEAK ISO_POS VOLTAGE | MEASURED PEAK ISO_NEG VOLTAGE |
---|---|---|---|
100.006 | 2.505 | 2.294 | 2.715 |
150.008 | 2.504 | 2.139 | 2.767 |
200.003 | 2.504 | 1.984 | 2.82 |
250.004 | 2.504 | 1.828 | 2.873 |
300.004 | 2.504 | 1.672 | 2.925 |
350.004 | 2.504 | 1.526 | 2.978 |
400.006 | 2.504 | 1.362 | 3.031 |
450.007 | 2.504 | 1.206 | 3.084 |
Figure 3-23 shows the deviations for POS ADC and NEG ADC voltages from normal conditions. POS and NEG are less than expected and constant when relays are closed. This behavior resonates to an isolation error from the high-voltage section to chassis ground.