Sine PWM generation using Arduino UNO

Maybe you should look up Taylor series.

The code you posted just uses a look up table to make sines from phase angles and a DDS (google it) to make the phase angles. If you want to run your inverter at  a constant frequency you don't need to bother with the DDS, just make a table of pulse widths and step though it at  a constant rate. You should synchronize the PW changes with the PWM frequency  - it might be worth interpolating between sine values from a table to avoid steps in the PWM settings.  I don't use Arduinos so I'm not sure if you have the level of control you would get in C or Assembler.

Is your project more concerned with hardware or software ?

What hardware are you using for the inverter itself.

MK

Thank you for your quick response. I am doing both hardware and software, and now i am at a stage where i have developed my hardware part and i am experimenting with the software. i am using MOSFET switches along with opto-couplers and drivers.

i would like to thank you again for your advice but I am looking for an explanatory guidance through the program itself, so i can find what is responsible for the output frequency, how I can invert the signal (without the use of logic gates) and guide it through a different output and how can i integrate a pwm algorithm independent from the control signal in order to control a couple of other switches! I know it may sound confusing but the general idea is to generate a SPWM signal for the H-bridge circuit, separate the positive from the negative half cycle. Along with that, I need another square pulse for additional purposes.

You're going to have to unpick the programme yourself to really understand it. Have you looked up DDS synthesiser yet (there's a lot on the web some of the stuff on Analog Devices' website is helpful).

I doubt very much that the Arduino can generate complementary PWM outputs - you would need a much more modern micro with better timers - are you stuck with the Arduino  or could you use an ARM Cortex (the ST parts (and others)) have much more sophisticated timers with complementary outputs, dead time control, emergency stop etc.

MK

I was just reading about this capability with the TivaC Connected Launch pad last night, it has very sophisticated timers and has all the above features and quadrature Encoder input for speed and direction sensing as well. A very powerful chip and quite an extensive support library

Hi bro,

nw i wna to make an inverter , generate spwm by aurdino

check this site

Lab3 - Laboratory for Experimental Computer Science

pwm out put frm aurino fed into low pass filter ,

in order to make invert pulses

use comparator.

output of filter fed into comparator (lm339)

signal fed into  +ve terminal of 1st cmparator

and -ve of 2nd comparator.

the other terminal are connected to the potential dividor ,itz rail voltage is 3.3 v frm aurdino.

nw u got 2 pulses

in order to get dample with orginal pulses.

use AND GATE logic

OUTPUT frm 1st compartor is fed into 1st input of AND GATE ,other input is orginal spwm pulse frm aurdino..

if u did nt get AND GATE use 2 NAND GATE for each pulse

inw u got 2 pulses, if u wan to isolate use optocoupler, then fed into driver (ir2110) ic

I believe he was looking for a software solution if he is still looking from last year July.