Some questions about IR2110 and IGBT based inverter frequency

[Nysix]

Hi all

I'm still having problems with my inverter circuit. Looking for informations about circuits and IR2110, I designed the following circuit:



My goal is control a AC motor changing its velocity, keeping the relation Voltage/Frequency be constant. The desired inverter's output is:



I'm using a 16F877A for generate the switching signal (four signals, one to each IGBT). Works fine on ISIS, but when I assembled this circuit in protoboard, it don't work. I'm no sure about what is not working properly...

- The IR2110 works in this frequency interval (5~60 HZ)?
- Vdd pin should be connected in +5V source and Vss in common ground circuit?
- The bootstrap capacitor is correct (330uF) for my application?

Thanks for any help and sorry for my english :/

 

[ch wazir]

urs designed cct. seem to be good,apparently no mistake is found.what problems you are facing need to be explained.however if you send the oscillator cct.of 16f877 more guidance will be submitted.regads

 

[Nysix]

Hi ch wazir.

The project don't work, only works in simulation... I have doubts about the time that the HIN pin can be high, because the frequency of my project is low (between 5 and 60 Hz), then the HIN pin may be high up to 200 ms... I don't know if the bootstrap capacitor works in this situation.

 

[ch wazir]

Hi ch wazir.

The project don't work, only works in simulation... I have doubts about the time that the HIN pin can be high, because the frequency of my project is low (between 5 and 60 Hz), then the HIN pin may be high up to 200 ms... I don't know if the bootstrap capacitor works in this situation.

plz upload the osc.cct in order to fix the problem,yours bootstrap cap seems accurate.i hve already worked on the cct you sent and its pretty good one.Regards

 

[Nysix]

Hi ch wazir,

Sorry, what means osc.cct? Where can I find it?

 

[ch wazir]

the signals coming to hin and lin pins of IR2110 i.e from osc.

 

[Nysix]

Ah, right. I upload in .jpg.



The first wave goes to HIN pin of IR2110 in left side;
The second wave goes to HIN pin of IR2110 in right side;
The third wave goes to LIN pin of IR2110 in left side;
The fourth wave goes to LIN pin of IR2110 in right side;

 

[Nysix]

Finally I found the problem
Is necessary put in high the LIN pin first. This charges the bootstrap capacitor

Thanks for all help.

 

[nup]

Can u please tell wat is the input given to Hin and Lin. please reply...............

 

[Nysix]

Hi,
I do not understand your question very well (I don't speak English very well). Could you repeat it?

Thanks.

 

[nup]

u have posted a inverter circuit with IR2112.
so what are u giving HIN and LIN pins of IR2112?

i hope my question is clear to u.

thanks.

 

[Nysix]

Hi nup,

I'm using a microcontroller (PIC16F877A). You can connect it directly through a resistor (470R or 330R), but a best option (in my opinion) is to use a 4049 inverter buffer and optocouplers (if the switching frequency is low).

 

[nup]

actually i am trying to simulate this circuit in pspice so wat should i connect at HIN and LIN?

 

[irfan ahmad]

aslam-o-alikum



first of all ir2112 requires 15v vdd and 7.5 to 15v in input of in2112(hin or lin)
i think you can make paires of controll inputs of ir2112
you can connect ic1 (hin) pin to ic2 (lin) and supose its name is b1(bising1)
and similarly ic1 (lin ) pin to ic2 (hin) and supose its name is b2(bising2)
now you have only two controll wires b1 and b2 to controll from micro controller.
yout can also use timer 1 to generate low frequency
and reload value of timer1 can be manipulated by using a c(language) variable.
and also in main subrutine you can change value of variable used for timer1.

 

[Nysix]

I'm using ISIS to simulate.

 

[steve000]

Hi all ^_^ :
i simulate the original H bridge circuit which Nysix post above on isis , the problem is when i add an atmega8 with program to generate the pulses for the drivers the isis give me a simulation error : " Time step to small " and i don't know why , then i delete the wire between the atmega8 and the drivers the simulation work fine but when i wire any thing to the atmega8 the problem still accors , i don't know the problem from what , Can anyone help me ?

 

[Nysix]

Hi steve000,

Sometimes this error occurs here, but I just ignore (the circuit works)

 

[electronicsbasecom]

I was read this topic slow from begining and I am glad that you realize thata you should charge bootstrap first, I also realize that alone

I was working with IR2112...similar to IR2110... at 4kHz frequency, but my new project have to work with 5Hz frequency. Any problem with such low frequency?

 

[Nysix]

electronicsbasecom,

I think that there aren't problem with 5Hz, my project works with frequencies among 5Hz and 60Hz. However, you need increase the bootstrap capacitor value (you don't said in your post, but I assumed that is a low value due the 4kHz frequency). Try a 330uF capacitor, I used this value in my project.