2 Replies Latest reply on Jun 25, 2020 11:49 PM by VasanthR_91

    CY8CKIT-037 Sensorless FOC Motor_i32IuvwAmplifierFactor

    MiRe_1322481

      Hello,

       

      we don't understand why in the example Sensorless FOC Motor the amplification factor

      Motor_i32IuvwAmplifierFactor is set to 4.16 (customer_interface.c , line 66).

       

      The actual configuration of the amplifier circuit should result in a factor of exactly 5.

       

      We would like to understand the reason for the difference since we have to adapt

      the firmware to our own hardware and need to be sure to calculate the factor

      correctly for our board.

       

      Best regards

       

      Michael

        • 1. Re: CY8CKIT-037 Sensorless FOC Motor_i32IuvwAmplifierFactor
          VasanthR_91

          Hi Michael,

           

          Motor_i32IuvwAmplifierFactor: is the factor of amplification multiples in amplification circuit as you have understood. I hope you are referring to  this application note too. Meanwhile I am checking why there is a difference in the factor value from the actual circuit value. I will update you at the earliest.

           

          Best Regards,
          Vasanth

          • 2. Re: CY8CKIT-037 Sensorless FOC Motor_i32IuvwAmplifierFactor
            VasanthR_91

            Hi Michael,

             

            As per the circuit, opamp non-inverting configuration is used- the gain calculation should also include the feedback capacitor in the design. ( One correction when the circuit is purely resistive the gain should be 6).

             

            To set this parameter accurately in your design you could use the oscilloscope to see the phase current value and compare with the  value read  on phase current value in IAR live watch. Calculate if the value read matches the measured value then adjust the gain set in project accordingly.

             

            Best Regards,
            Vasanth