| 摘要 |
A battery pack voltage measuring circuit of a hybrid electric vehicle and a leakage current blocking method are provided to suppress an unnecessary leakage current by turning off the voltage measuring circuit during an ignition off state. When a pack voltage is applied from a battery pack(10), a high frequency noise is removed from the pack voltage and the result is delivered to an insulation amplifier(22) through a primary second-order active filter(21). The pack voltage is amplified and delivered to a secondary differential amplifier by the insulation amplifier. A differential amplifier(23) recovers a voltage signal from the secondary pack voltage signal from the insulation amplifier and delivers the voltage signal to a secondary second-order active filter. The secondary active filter(24) removes the high frequency noise from the pack voltage signal and delivers the result to a BMS(Battery Management System). The battery pack is connected to a voltage measuring unit(20). A voltage measuring relay(11) is installed on a voltage measuring unit connection side of the battery pack. The BMS(30), which determines whether an ignition key is turned on, turns on/off a contact switch of the relay. |
