DRM028 — Rev 0
MOTOROLA
Freescale Semiconductor, Inc.
Figure 3-10. Distributed Back-EMF by Unbalanced
Channel 1 in
Figure 3-11
the other phase (channel 2) is not affected because it faces balanced
mutual capacitance. The unbalance was purposely made by adding a
small capacitor on the motor terminals, in order to better demonstrate
the effect. After the unbalance was removed the "branch" voltage is
clean, without any spikes.
BLDC Motor Control
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Brushless DC Motor Control Theory
Capacity Coupling
shows the disturbed "branch" voltage, while
BLDC Motor Control
Designer Reference Manual
35