PPA55xx Quick User Guide
Page 50
6.5.1 PWM MOTOR DRIVE MODE
The nature of the waveforms produced in a PWM motor drive application makes
measurement of the fundamental frequency difficult. In this section we will look
at the switching and fundamental frequencies and how frequency lock and filters
will allow the correct measurements to be displayed on such a complex
waveform
Test device: 1 x Inverter/Motor test unit (set at 65Hz)
Leaving the PPA55xx in “normal” app mode take note of the frequency
measurement
In “normal” app mode the PPA55xx is
locking onto a switching frequency /
high frequency noise of 4 KHz with no
filtering applied. This can be used as
a guide when selecting a frequency
filter from within the PWM motor
drive application