Kinetis MicrocontrollersのトピックRe: Implementing a 50Hz PLL for on-grid inverter https://community.nxp.com/t5/Kinetis-Microcontrollers/Implementing-a-50Hz-PLL-for-on-grid-inverter/m-p/685221#M42189 <HTML><HEAD></HEAD><BODY><P>I'm guessing you are looking to clean up the incoming zero crossing signal to synchronize with the line?</P><P><BR />Synchronized Oscillator as shown in Figure-11 will make things a lot easier by starting with a clean signal.</P><P><A class="link-titled" href="http://cds.linear.com/docs/en/application-note/an12fa.pdf" title="http://cds.linear.com/docs/en/application-note/an12fa.pdf">http://cds.linear.com/docs/en/application-note/an12fa.pdf</A>&nbsp;</P><P>Feed the signal into one of the Input Capture timer pins.</P><P></P><P>If dealing with three-phase will need two zero crossing detectors to determine phase rotation automatically.</P><P>This can also help as at some phase angles the transistors/SCRs will be firing at the zero crossing point on one of the phases.</P><P></P><P><A class="link-titled" href="https://hackaday.io/project/19875-software-phase-locked-loop" title="https://hackaday.io/project/19875-software-phase-locked-loop">Software Phase Locked Loop | Hackaday.io</A>&nbsp;may be of some interest as well.</P><P></P><P>More on&nbsp;<SPAN>Synchronized Oscillators here:</SPAN></P><P><A class="link-titled" href="http://web.archive.org/web/20071216210921/http://www.unusualresearch.com:80/AppNotes/AppNotes.htm" title="http://web.archive.org/web/20071216210921/http://www.unusualresearch.com:80/AppNotes/AppNotes.htm">My favorite Application Notes and Old Obscure Data Sheets</A>&nbsp;</P></BODY></HTML> Thu, 27 Jul 2017 13:55:41 GMT bobpaddock 2017-07-27T13:55:41Z Implementing a 50Hz PLL for on-grid inverter https://community.nxp.com/t5/Kinetis-Microcontrollers/Implementing-a-50Hz-PLL-for-on-grid-inverter/m-p/685220#M42188 <HTML><HEAD></HEAD><BODY><P>Hello Everyone,</P><P></P><P>Are there any examples on implementing a 50Hz digital PLL using the Kenetis K60 MCU?</P><P>If there are any ready made ICs avalable from NXP it would be really helpfull.</P><P></P><P>Thanks,</P><P>Arun</P></BODY></HTML> Thu, 27 Jul 2017 06:56:46 GMT https://community.nxp.com/t5/Kinetis-Microcontrollers/Implementing-a-50Hz-PLL-for-on-grid-inverter/m-p/685220#M42188 arunkumar1989 2017-07-27T06:56:46Z Re: Implementing a 50Hz PLL for on-grid inverter https://community.nxp.com/t5/Kinetis-Microcontrollers/Implementing-a-50Hz-PLL-for-on-grid-inverter/m-p/685221#M42189 <HTML><HEAD></HEAD><BODY><P>I'm guessing you are looking to clean up the incoming zero crossing signal to synchronize with the line?</P><P><BR />Synchronized Oscillator as shown in Figure-11 will make things a lot easier by starting with a clean signal.</P><P><A class="link-titled" href="http://cds.linear.com/docs/en/application-note/an12fa.pdf" title="http://cds.linear.com/docs/en/application-note/an12fa.pdf">http://cds.linear.com/docs/en/application-note/an12fa.pdf</A>&nbsp;</P><P>Feed the signal into one of the Input Capture timer pins.</P><P></P><P>If dealing with three-phase will need two zero crossing detectors to determine phase rotation automatically.</P><P>This can also help as at some phase angles the transistors/SCRs will be firing at the zero crossing point on one of the phases.</P><P></P><P><A class="link-titled" href="https://hackaday.io/project/19875-software-phase-locked-loop" title="https://hackaday.io/project/19875-software-phase-locked-loop">Software Phase Locked Loop | Hackaday.io</A>&nbsp;may be of some interest as well.</P><P></P><P>More on&nbsp;<SPAN>Synchronized Oscillators here:</SPAN></P><P><A class="link-titled" href="http://web.archive.org/web/20071216210921/http://www.unusualresearch.com:80/AppNotes/AppNotes.htm" title="http://web.archive.org/web/20071216210921/http://www.unusualresearch.com:80/AppNotes/AppNotes.htm">My favorite Application Notes and Old Obscure Data Sheets</A>&nbsp;</P></BODY></HTML> Thu, 27 Jul 2017 13:55:41 GMT https://community.nxp.com/t5/Kinetis-Microcontrollers/Implementing-a-50Hz-PLL-for-on-grid-inverter/m-p/685221#M42189 bobpaddock 2017-07-27T13:55:41Z