Posted on July 19, 2012 at 05:39Refer to AN1130 on page 15,
''If the motor speed is suddenly increased by the user so the Z event will happen earlier. If BEMF signal is already be positive when the phase extremity becomes a floating point thus the signal will not cross the threshold voltage and the ST72141 will not detect the End of demagnetisation event. As a consequence, the ST72141
won’t open the Z event detection window.
We force an End of demagnetisation event and so the Z window detection is opened in all cases.''
Can someone please explain how to detect Z event before End of D is not finish yet? and how/when we can force D event in this case?
Do you have timing diagram of phase current and phase voltage similarly to figure 9. in case of Z event is happen early.
Thanks.
