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TMS320F28388D: Simulink Embeded Coder

Part Number: TMS320F28388D


Hi,

I am using Simulink R2020 to code F28388D, I have to implement a PLL for 400 Hz system. My input is pure 3 phase supply without any harmonics. But my PLL output that I use to generate PWM is oscillating. My PWM does synchronize but it keeps on jumping.

I have two questions.

If some one please have a look at the simulink file and see if I am missing sonething? Are my blocks properly configured? I am using SOC0 for all 3 ADC channels. Does using a same SOC for multiple channels harms the response? I am using same trigger with equal acquisation window of 50 cycles. My ADC clock is set at 66.6 MHz. I am using a 300kHz PWM signal to trigger my all 3 ADC chanels.

Second Question is regarding sampling time. Is there a way I could check if my sampling rate is too fast for my code? For this PLL I can reduce my sampling time to 30-50kHz but then for current control of a converter I need to operate at sampling rate of 300-500 kHz as my switching frequency would be atleast 100kHz. So it is very imporatant for me to know if my sampling rate is not too high. And also is simulink an efficient way of coding ? I have wasted now few months on this problem and now I am wondering if some expert can give their opinion regarding directly coding the controller Vs using simulink embeded coder.

CC: I am not being able to attach my simulink file. Can some one comment how can I do that?

https://www.youtube.com/watch?v=sDRYE8_c9I8

Link to the output of PLL

Thank you 

  • Bilal,

    Thanks for reaching out to the E2E forum.  Based on your question I'm going to pull a few different people into this thread, from both TI and potentially the MW.

    Best,

    Matthew

  • Thank you very much. Is there any way I could share my simulink model with you experts so I could get you opinion ?

  • Hi,

    For the first part of your question is application specific and the winning combination would be the files we may need to review and connect it to right people. This can happen if you contact our support.

    For the second part it is likely you are exploring the multi rate execution modeling approach. Your application has 2 parts that have different requirement for execution rates. We have one shipping example that on multi rate execution using the rate transition blocks.