Question

Are the following statements true (T) or false (F) of the electromagnetic compatibility in power electronics?

a) Component layout of the power converter does not affect the EMI coupling, just the
switching speed.
b) In power converter, increasing the distance between two wires is a good option to re-
move noise coupling.
c) The frequency content of a PWM controlled output voltage is defined only by the fun-
damental (modulating signal) and the carrier frequencies.
d) The inverter end of the motor cable has no impedance mismatch when there is no filter
installed.
e) With a six-pulse diode rectifier, the grid current will meet the grid standards for a kilo-
watt range motor inverter without a grid filter.
f) A common-mode choke placed at the inverter output will eliminate motor terminal over-
voltage.
g) Replacing IGBTs with GTOs as the inverter switches will improve the power quality
(less noise) and improve the efficiency of the drive.
h) Modulation strategy of an H-bridge feeding the will not affect the generated common-
mode voltage.
i) Motor bearing currents will are harmful for the motor, but will not conduct any noise to
the surrounding equipment. Noise = CM/DM voltage
j) EMI is usually invisible for the converter measurement (for example DC link voltage,
output current).

Answer 1