THS II (TOYOTA HYBRID SYSTEM II)
02DTH82Y
Reactor
Nominal Voltage
of DC 244.8 V
Boost IPM
IGBT
(1)
(2)
IGBT
ON
Inverter
02DTH83Y
(1)
(2)
Maximum Voltage
of DC 650 V
OFF
TH-50
Boost Converter Control
1) General
The boost converter boosts the nominal voltage of DC 244.8 V (for the HV battery) up to a maximum
voltage of DC 650 V, in accordance with the signals provided by the THS ECU via the MG ECU.
The inverter converts the alternating current generated by MG1 or MG2 into a direct current. The
boost converter drops the maximum voltage of DC 650 V to nominal voltage of DC 244.8 V (for the
HV battery) in accordance with the signals provided by the THS ECU via the MG ECU.
The boost converter consists of a boost IPM (Intelligent Power Module) with built-in IGBTs
(Insulated Gate Bipolar Transistors) that effect switching control, and a reactor that stores (and
charges) electrical power.
2) Voltage Boost Conversion Function
The function of the boost converter to boost the nominal voltage of the HV battery from DC 244.8
V to maximum voltage of DC 650 V flows as described below.
The IGBT (2) turns ON, causing the
electrical power of the HV battery
(nominal voltage of DC 244.8 V) to
charge the reactor. As a result, the
voltage in the reactor rises.
In the next stage, when the voltage in
the reactor rises to maximum voltage
of DC 650 V, the IGBT (2) turns OFF,
causing a counter electromotive force
to be created.
Induced by the counter electromotive
force that is created, the electrical
power (maximum voltage of DC 650
V) that is charging the reactor flows
into the inverter.
