Determination of the current transfer ratio h
of the BJTs using the
corresponding datasheets. h
is dependent on the previously calculated
current requirement per booster stage.
Calculation of the required current of the driver IC needed to drive the booster
stage(s). This is based on the current transfer ratio and the number of existing
An example for the calculation follows:
Calculation of a bipolar booster stage
6.4 Driver voltage supply
IGBTs are turned on with a positive gate voltage of nominally 15V. To switch off, either
0V or a negative voltage of up to -15V is applied to the gate. The advantages and
disadvantages in this regard are discussed in detail in chapter
In any case, these
gate voltages must be provided by the gate drive unit and should be an isolated
potential, as required by most topologies. In this chapter, therefore, the circuit aspects
are examined in more detail, which are relevant to the gate drive supply voltage.
Furthermore, the power supply provides for the isolation of the power electronic
switches to each other. Depending on the application therefore, the corresponding
standards for clearance and creepage distances have to be observed as well as
compliance with the test voltages. Below are the designations of the relevant standards
for industrial and traction applications. In the automotive sector for (hybrid) electric
vehicles there is currently no approved insulation coordination. At this stage, reference
ismade to the current industry standards in theseapplications.
, "Electronic equipment for use inpower installations"