Problem with Space Vector PWM with Concerto H63C2
Altair EmployeeSubmitted by Dimitris on Tue, 06/14/2016 - 15:59
Hi,
I have generated the cascaded controllers (inner dq and outer Vdc) for my active rectifier and I am using sPWM, which works fine. Now I want to use space vector modulation (not just 3rd harmonic) to minimise switching losses.
My experimenter kit is the Concerto H63C2 and thus i use F280x library blocks so far and TI 32-bit DIgital motor control blocks (Clack and Park transformations).
1) I saw the discussion between the SVP PWM and the Full Compare PWM in the forum, and I would be keen to go for the second (Full compare) but this is in the F281x lib and when I try to use it the compiler cannot generate an output file. Probably makes sense!!! 2)So, I tried the TI 32-bit digital motor control library and the 'Space vector PWM' block (I use the space vector generator quadrature control block from the same library, to get the duty cycles and works just fine , + the Park and Clack transformations). However, this block ('Space vector PWM') doesn't allow to generate the output file when compiling it. Is there any incompatibility with my DSP? It says when compiling it _F281x_EV1_PWM_Inti and _F281x_EV1_PWM_Update (undefined symbols).I assume that the block have been made only for the F281x DSPs by mistake and not for all the DSPs as it should? Because I use the f280x and I use other TI 32-bit digital motor control library blocks with no problem ....Can you please advice if I am doing something wrong or the block needs to be changed in order to work for concertos?
Is there any way to use the Full Compare PWM with my DSP (for f280x), as I would like to set the dead time and gives better control of my actions.
Thank you in advance for your time.
Kind regards
Dimitris
Answers
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Submitted by imatalon on Wed, 06/15/2016 - 17:33.
Hi Dimitris,
Could you please upload the diagram as well as the cmd text?
Kind regards, Isi
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Submitted by Dimitris on Wed, 06/15/2016 - 17:53.
Hi Isi,
Here are the diagram and a print screen of the cmd text. If I delete the SPACE vector Block from the diagram it generates the .out file.
Kind Regards
Dimitris
<?xml version="1.0" encoding="UTF-8"?>
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Submitted by imatalon on Wed, 06/15/2016 - 17:59.
The error should be above the part you took a screenshot of. Right click and Select all and then press enter. Paste it on a txt file.
Thanks
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Submitted by Dimitris on Wed, 06/15/2016 - 18:39.
This is it
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Submitted by pete on Wed, 06/15/2016 - 22:45.
Dimitris, The 'Full Compare' block is meant for the older F281x part (yes, I know it's odd that F281x is an older part than F280x, but that's how it is). The f280x series (of which your F28M36x is a part) uses the ePWM which lets you adjust deadband as well as a host of other things. We have a number of posts explaining how to set various parameters of the ePWM. Please replace the 'Full Compare' with an ePWM block.
Pete0 -
Submitted by Dimitris on Wed, 06/15/2016 - 23:15.
Dear Pete,
Thank you for your answer, however I do not use the Full compare! The diagram I provided has the Space Vector PWM block from the TI 32bit Digital Motor Control Blocks!
I am currently using the ePWM block (3 of them actually for my three phase rectifier) of the F280x lib, for sine triangle PWM and 3rd harmonic injection PWM, without any problem. However, I want to use Space Vector Modulation now, and the TI 32bit Digital Motor Control Block 'Space Vector PWM' block that is related to this, doesn't work as I stated at my initial message. [However I use the Clark Transform,Park Transform (and their inverse) transformations as well as the Space Vector Generator (quadrature control) block from this library without any issues.]I get he sense that this block has been configured for the f281x core for some reason, while it should be available to my F280x DSP as the other blocks of this library (TI 32bit Digital Motor Control Blocks).
How can I use the 3 independent ePWM blocks to feed to them, the duty cycles generated by Space Vector Generator (quadrature control) without doing effectively 3rd harmonic injection instead of Space vector modulation as I would like to. I assume I need a block that controls all 6 pwm channels (Space vector PWM block) so that the duty cycles calculated can be fed to it and it will switch on and off the MOSFETs accordingly. IF there is any other solution please let me know.
Thank you for your time.
Kind Regards
Dimitrios
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Submitted by pete on Wed, 06/29/2016 - 23:19.
Please use the attached blocks for Space Vector PWM
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