DTC P0A94-442: DC / DC Converter Performance: Description

The boost converter boosts the 288 V DC from the HV battery to a maximum of approximately 650 V DC. The inverter converts the voltage that has been boosted by the boost converter into alternating current, which is used for driving MG2 and MG1. When a motor generator operates as a generator, the alternating current that it creates is converted into direct current by the inverter. Then the boost converter drops this voltage to direct-current of approximately 288 V in order to charge the HV battery.

Fig 1: DC/DC Converter Performance - Circuit Diagram

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The MG ECU uses a voltage sensor (VL) that is built into the boost converter to detect the high voltage before it is boosted. It also uses a voltage sensor (VH) that is built into the inverter to detect the high voltage after it is boosted. Based on the voltage before and after it is boosted, the MG ECU controls the operation of the boost converter to boost the voltage to the target voltage.