AN863 Datasheet, PDF (18/22 Pages) STMicroelectronics – Improved sensorless control with the ST62 MCU for universal motor

IMPROVED SENSORLESS CONTROL WITH THE ST62 MCU FOR UNIVERSAL MOTOR
Figure 12. Variation of the current at zero-crossing it0 versus firing delay td at
600 rpm, while the load is varying. The cross-hatched area is not
allowed, as friction keeps the motor stalled for very large firing
delays. The set of vertical lines is a graphic representation of the
table contents.
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