Kinetis Motor SuiteのトピックRe: Spread Spectrum PWM https://community.nxp.com/t5/Kinetis-Motor-Suite/Spread-Spectrum-PWM/m-p/758632#M480 <HTML><HEAD></HEAD><BODY><P>Geoffrey,</P><P></P><P>KMS doesn't feature spread spectrum PWM by default.&nbsp; You should be able to add support for this into KMS.&nbsp; You would do this by replacing the SVPWM block with a new block of your own design.</P><P></P><P>KMS sets up the PWMs to be center-aligned so that the ADC sample is taken in the middle of the PWM period.&nbsp; So the ADC sample would occur in the same place regardless if the frequency is changing.&nbsp;&nbsp;In addition to modifying the frequency, you would also need to change the deadtime counter since the FlexTimer handles the deadtime insertion.</P><P></P><P>I don't think varying the PWM frequency by a few kHz would impact the control loops within KMS.</P></BODY></HTML> Wed, 03 Jan 2018 14:04:00 GMT linestream-adam 2018-01-03T14:04:00Z Spread Spectrum PWM https://community.nxp.com/t5/Kinetis-Motor-Suite/Spread-Spectrum-PWM/m-p/758631#M479 <HTML><HEAD></HEAD><BODY><P>Does the KMS support spread spectrum PWM?&nbsp; &nbsp;Has anyone attempted to modulate the pwm frequency to spread out the switching noise?</P></BODY></HTML> Wed, 03 Jan 2018 01:06:15 GMT https://community.nxp.com/t5/Kinetis-Motor-Suite/Spread-Spectrum-PWM/m-p/758631#M479 geoffreylansber 2018-01-03T01:06:15Z Re: Spread Spectrum PWM https://community.nxp.com/t5/Kinetis-Motor-Suite/Spread-Spectrum-PWM/m-p/758632#M480 <HTML><HEAD></HEAD><BODY><P>Geoffrey,</P><P></P><P>KMS doesn't feature spread spectrum PWM by default.&nbsp; You should be able to add support for this into KMS.&nbsp; You would do this by replacing the SVPWM block with a new block of your own design.</P><P></P><P>KMS sets up the PWMs to be center-aligned so that the ADC sample is taken in the middle of the PWM period.&nbsp; So the ADC sample would occur in the same place regardless if the frequency is changing.&nbsp;&nbsp;In addition to modifying the frequency, you would also need to change the deadtime counter since the FlexTimer handles the deadtime insertion.</P><P></P><P>I don't think varying the PWM frequency by a few kHz would impact the control loops within KMS.</P></BODY></HTML> Wed, 03 Jan 2018 14:04:00 GMT https://community.nxp.com/t5/Kinetis-Motor-Suite/Spread-Spectrum-PWM/m-p/758632#M480 linestream-adam 2018-01-03T14:04:00Z