User Guide

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2021-01-29

System design

User guide for REF-22K-GPD-INV-EASY3B

A reference design for a general purpose drive

The gate layout of the high-side IGBT of the phase U is shown as an example in Figure 15. The traces of the

emitter and gate trace are on top of each other, which minimizes any parasitic inductances.

gate

emitter

minimize the stray

inductance by overlaying

gate and emitter trace

Figure 15

Gate layout of the high-side IGBT of phase U

3.3

Inverter cooling concept

A three-channel cooling system provides the cooling of the inverter, as seen in Figure 1 and Figure 16.

The main cooling of the IGBT is done by a heat sink and an integrated 92 mm fan with a temperature controlled

flowrate of 0-270 m³/h. The air is drawn in the bottom of the unit and blown up through the heat sink to the

outlet at the top of the enclosure, assuming a normal wall mounting position.

A 52 mm auxiliary fan cools the DC-link capacitors and operates at a constant speed with a flow rate of 20m³/h.

As shown in Figure 16 the air is blown into an air channel at the bottom of the capacitor array. To provide an

improved cooling over the entire surface of each capacitor the air is directed up one side and then channeled

via small slits between each capacitor and then finally along the side of the heat sink to the air outlet at the top

of the enclosure.

A second 52 mm fan, also operating at a constant speed, cools a third channel containing the EMI filter. The air

flows beside the heat sink and over the indictors and capacitors of the EMI filter. This cooling channel has a

separate air outlet at the top of the enclosure.