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Reference Number: AA-02024// Views: AA-02024// Created: 2021-07-14 18:58:20// Last Updated: 2021-07-15 16:34:03 HowTo How to configure an offset to your external resolver excitation source There are three different methods to configure an offset to your external resolver excitation source. First method : with loadIn port Depending on the bitstream you have, you will find this LoadIn port : This LoadIn port allows you to set an offset for the resolver as you can see in the firmware model : In order to set the offset value the LoadIn block should be used and set with the correct port number : For any question on how to set the 2 inputs of the LoadIn block please contact the Technical support Second method : with the hardware Analog inputs are differential, each channel has a (+) terminal and a (-) terminal : For example, the first analog input channel will read the difference between the (+) terminal and the (-) terminal : CH00 = (CH00+) - (CH00-). so if your external excitation has an offset you can cancel it by connecting the same value of the offset in CH00-. Example : Let's say your external excitation is : A*Sin(2*pi*f*t + phase) + offset Then you should connect the external excitation (with offset) to CH00+ and connect a DC signal with the same amplitude than the offset to CH00-. Your analog input will read exactly CH00 = A*Sin(2*pi*f*t + phase). note : This method is compatible with all the firmwares in comparison with the first method that requires a specific bitstream. Third method : Schematic editor If you have a schematic editor firmware, click on the PMSM block and go to the resolver section. After setting the excitation source type to be "external", you will be able to set an offset for your desired analog input channel : |