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CHAPTER 2: EXPERIMENTAL IMPLEMENTATION OF MATRIX CONVERTER DRIVE
Figure 2.5: Matrix converter used
three circuits with a digital output to sense the direction of the output current (needed
for the four step commutation sequence), three LEM LAH 25-NP current sensors[39]
and three LEM LV-25-P voltage sensors[40], one of the latter ones is used for the clamp
circuit, to detect whether there is an over-voltage on the clamp capacitors. The board
needs two different supplies, +5V for the logic and the gate drives and a dual supply
±15V for the current and voltage transducers. The control signals for the IGBT are
grouped in a 26-pin header, located at the center top of the converter, their function
is described in Table 2.1. Their numbers reflect the one on the PCB design, and the
connector’s key shroud corresponds to the table’s left hand side. The signal’s names
are defined this way: the number in the signal name specifies on which input phase
the IGBT terminal C1 is connected to, 1,2 and 3 represent phases R,S and T. An F (for-
ward) or an R (reverse) specify which of the two IGBT within the module (Fig. 2.2),
then the last character is to specify which of the output phases the IGBT terminal C2 is
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