[SOLVED] Pic 16f876a Pure Sinewave inverter

[codewiz]

full-bridge inverter pdf

Hi Taner. Sorry to disturb you. please, can you give the normal voltages expected for the different input signals for the mcu. I mean, on normal working condition, what voltage or range of voltage should curr_l , curr_h , V_OUT , volt etc. measure. Thanks in advance because i want to modify design to handle more load.

 

[Taner]

pic based sine wave inverter

Hi codewiz,
V_OUT = 2.5V +/- max 1.5V (min 1V, max 4V, middle point 2.5V, sine wave)
curr_h = 2.5V +/- max 1V (min 1.5V, max 3.5V, middle point 2.5V, sine wave)
curr_l = 2.5 V +/- max 0.25V (middle point 2.5V, sine wave)
volt = 4.45 - 4.82 Vdc
Stdby = 0 - 5 Vdc
b/a - depending on MOSFET Rds and output current magnitude, approx. 1 - 2V max.

Best regards.
Taner

 

[sekki]

secondary-side pwm sine inverter schematics

Hello OBIALOR

Attach a sorce code

pic---SQUARE wave(isolate)---lpf---lpf---sine ref---comp---full brige--------out
\---feed back------\

use pic basic compiler

 

[OBIALOR]

pic sine wave inverter code source

THANK YOU SEKKI,IN YOUR SCHEMATIC YOU USE PIC16F876, WHY F84-50HZ-60HZ? YOU MENTION ON THE PDF FILE.

 

[sekki]

pic sine wave inverter circuits

Hello OBIALOR

The file name does not matter.
Finally, the PIC16F873 For each monitoring.

Sorry able to English

 

[OBIALOR]

pwm inverter c code

OK, DID YOU HAVE THE PCB?
ALSO I HAVE COMPILE THE SOURCE CODE AND IS OK, PLEASE GIVE ME MORE DETAILS ON THE COMPONENTS.

 

[codewiz]

es.co.th

Thanks Taner for the signal voltages. it means that thevoltages are divided by the resolution of ADC (0.0196) for 8bit mode to give the digital value for coding. for instance, input signal of 1.5v will give approx. 77 as digital value. am i right? please correct me if i'm wrong. i was wondering what V_BAT is at 10.8v and 16v because in your code you divided the digital value by 32 ie [acc_v_avg = acc_v_temp>>5]. it seems not to give me value comparable to "acc_min_l" and "acc_max_h". clear my doubt. i may be getting something wrong. thanks for your support.

 

[khossanr]

pic inverter circuit

Dear all, I m new here. I want to make a microcontroller programming board using serial/USB port,with software,schematic,PCB, if anybody please help me...

Thanks with advance.

 

[howidam]

sine wave inverter reference design avr

Dear friends ,
i don't understand how to create the LUT of sin wave or level correction that used to configure pic register to control PWM. could you help please
how could i get 81,162,.....

Thanks,
wait your reply

 

[santhosh5673]

pure sine wave inverter pcb

Hi Taner/Codewiz

Sinewave Lookup Table calculation:
Ki = PWMmax*sin(i*180/n),
where:
PWMmax=1023
i = 0,1,2,...,n
Best regards.
Taner


I can't be able to get
sine_wave[32] = {81,162,241,318,392,462,527,588,642,691,733,768,795, 815,827,831,827,815,795,768,733,691,642,588,527,462,
392,318,241,162,81,0}

For examle if i = 32 starting from say 1 to 32

when i = 1 ; Ki = 1023 * sin(180/32) = 100
when i = 2 ; Ki = 1023 * sin(360/32) = 200
when i = 3 ; Ki = 1023 * sin(3*(180/32)) = 296
when i= 4 ; Ki = 1023 * sin(4*(180/32)) = 391
when i = 5 ; Ki = 1023 * sin(5*(180/32)) = 482 and so on.

I had calculated using a calculator, if this is not the way to calculate, can you please suggest me how to get those values.

Also how to get the volt_ref_sin[32] = {.........} values.

Please suggest, I am doing a project work on PIC based Inverter.

Thanking you
santosh

 

[Taner]

pic pwm sine

Hi santosh,

Sinewave Lookup Table calculation:
Ki = PWMmax*sin(i*180/n),
where:
PWMmax = 0 -:- 1023
i = 0,1,2,...,n

PWMmax = 831 in this Inverter design.

Best regards.
Taner

 

[howidam]

chinese inverter for ups in karachi

Dear friends,
why you deciede to use 831 as PWMmax , how to calculate it ? what is the design parameter used to get this value (is it function in Vin,Vout......)

 

[santhosh5673]

programma in c per inverter pwm sine wave

Hi Taner/Howidam

Taner thank you for the support
Hi howidam, I too thought of asking the same question of how PWMmax = 831 has been got.

---> Taner
1] If PWMmax = 831, then do we need to change the value in the declaration
const long pwm_max=1023; to
const long pwm_max=831; ????

2] I was unable to come up to get the values of
volt_sine_ref[32] and delta_corr[32], Please guide me in this regard with equations for the same.

3] Also, I tried to search some documents related to "programming pic16* in C" but could't got. Is that can be got only by installing ccs c compiler or can I have some documents (pdf) for learning all the c programming syntax (instructions) like read_adc(), output_high(), set_adc_channel() etc ??. If you have please share the programming pdf, docs.

4] I was unable to understand some keywords like ADC_READ_ONLY, ALL_ANALOG, ADC_CLOCK_DIV_32, etc. Where does these words have been declared ??

Please provide me the solution.

santhosh

 

[santhosh5673]

inverter pwm sine wave

Hi prends/Taner :|
I just downloaded ccs c 30 days demo version, where I just ruuned the pwm_inverter.c program. It has given .h file where all the #defines have been listed.
But still for the other first 3 q's I coul't got the solution. If anybody have "programming pic16f* using c" documentations please share.

When i compiled the .c file I got a error: program is too large - sine_pwm

I guess program memory is not sufficient here. Is there any solution for this, please suggest.

santhosh

 

[MRahman]

pic pwm converter

Hi Mr. Santhosh

Please use CCS C -V4 you should be able to compile it. **broken link removed** -for compiler.
Thank you
Mohamad

 

[codewiz]

16f876a ccs

Thanks Taner for the signal voltages. it means that thevoltages are divided by the resolution of ADC (0.0196) for 8bit mode to give the digital value for coding. for instance, input signal of 1.5v will give approx. 77 as digital value. am i right? please correct me if i'm wrong. i was wondering what V_BAT is at 10.8v and 16v because in your code you divided the digital value by 32 ie [acc_v_avg = acc_v_temp>>5]. it seems not to give me value comparable to "acc_min_l" and "acc_max_h". clear my doubt. i may be getting something wrong. thanks for your support.

I still have doubt about the above. I may not really get the reason why ">>" is often used in C for ADC. Please Taner I'm still waiting for help. Thanks.

 

[howidam]

pic16f876a based dc-ac inverter circuits

dear friends,
why we set PWMmax as 831 and how we can map the given sine wave LUT to a real time values like 20us,... duty cycle of the sine.
and please , if any one can guide me in concept and how to construct the LUT.
thanks
best regards,

 

[asif hameed]

16f876a

Hi Mr. Taner,

thank you for your great design but i am facing the following problem.
After Assembeling inverter and burning the pic, i tried to fire it up. but only red and green led's are blinking alternatively at a 1 sec. interval. I had checked every track and connection and its all ok. On checking on Osciloscope the A/B and OE signals from pic are not generating, but the pwm signal is there. What would be the problem? plz help.

i will be highly obliged.

 

[Taner]

pwm inverters schematic

Hi asif hameed,
Active level of OE signal is low level (Log. "0").
A/B direction signal is a square wave signal with frequency 50Hz and 50% duty cycle.
For correct work of the inverter all feedback signals must be connected to the PIC MCU, with normal working levels.

Best regards.
Taner

 

[asif hameed]

circuit pwm for inverter

Thank you for your quick reply.

I have simulated the invereter in proteus and after some struggling, achieved the simulated output. I found that my system is lacking the feedback from FET's i,e. a/b which must be from 1-2 volts as you mentioned earlier. i am using FET's P75NF75 instead of IRL3803, do you think that it can cause the problem? I am working on it and hopefully will update you tomorow. I am uploading the photo of my version of inverter .[/img]