Programming pic

[Phoenix1996]

Hello
I am designing an inverter for input ranging from 220-440v DC 13A, and output of 220v ac 50hz, it is designed for 5kw, using pic30f2010 as an oscillatory circuit.


Can any body tell me how to produce SPWM of 40khz using pic PWM pins 23-26, 1L,1H, 1L,1H to drive an IGBT H-bridge using Sin wave lookup table of 200+ values of steps per cycle.

I am using pi filter using 6mH choke and 10uf/440V foil capacitor.

I need to add feedback system that checks the output voltage and increases dutycycle of SPWM accordingly.

This is the first stage of the inverter, later on I want to ad LCD to show these values.



I want the inverter to switch off when the I put voltage is less than 220V DC from PV array.

Ps: do you think ACS712 module at the output to check the current sensing and give feedback and also check shortcut parameters.
I am planning to use Lm393 for this comparison.

Kindly guide me in this regard.



Thanks

 

[Aussie Susan]

That is a very old DSP chip. If this is really a new design then you are better of selecting a much newer chip (generally more memory, faster, cheaper etc.).
If you are using s sine lookup table then why do you need a DSP chip at all?
There are a lot of designs out there for exactly what you are looking for - i.e.driving an H-bridge.
When you also talk about filters etc, it seems to be mtmat you are getting a little ahead of yourself with the design.
Susan

 

[Tahmid]

Hello
I am designing an inverter for input ranging from 220-440v DC 13A, and output of 220v ac 50hz, it is designed for 5kw, using pic30f2010 as an oscillatory circuit.


Can any body tell me how to produce SPWM of 40khz using pic PWM pins 23-26, 1L,1H, 1L,1H to drive an IGBT H-bridge using Sin wave lookup table of 200+ values of steps per cycle.

I am using pi filter using 6mH choke and 10uf/440V foil capacitor.

I need to add feedback system that checks the output voltage and increases dutycycle of SPWM accordingly.

There is some information I have covered in the past:

1. https://tahmidmc.blogspot.com/2011/01/generation-and-implementation-of-sine.html
2. https://tahmidmc.blogspot.com/2023/11/smartsinepy-and-example-of-gui.html
3. https://tahmidmc.blogspot.com/2013/02/demystifying-use-of-table-pointer-in.html
4. https://tahmidmc.blogspot.com/2012/11/feedback-in-sine-wave-inverter-pic16f.html

Those contain some implementation details that you should be able to adapt to your application using the dspic30.

This is the first stage of the inverter, later on I want to ad LCD to show these values.



I want the inverter to switch off when the I put voltage is less than 220V DC from PV array.


Ps: do you think ACS712 module at the output to check the current sensing and give feedback and also check shortcut parameters.
I am planning to use Lm393 for this comparison.

Kindly guide me in this regard.



Thanks

You can attenuate (and isolate if needed) your DC input and feed it to an ADC to sense the input voltage. Then, in software, you can compare against your 220V reference. Alternately, you can use a comparator like the LM393 you mentioned and sense the output of the comparator. Which part of this gives you trouble?

If you're working with these voltages, you should proceed carefully especially if you're not sure of what you're doing.

Thanks,
Tahmid.