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vanisri
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How to create PWM pulses by comparing the sinusoidal wave with high frequency triangular wave in labview

i need pwm pulses by comparing sinusoidal wave with high frequency triangular wave in labview . is it possible to create this pwm pulses with pulse width modulation technique. please help for this . since i have to drive the inverter circuit using this pulses for various output

 

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bruno_costa
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Re: How to create PWM pulses by comparing the sinusoidal wave with high frequency triangular wave in labview

Why you need generate a triangular wave? Is a sinusoidal wave a input of your system? If dont you can generate a table of pwm periods and the multuply by a scalar to control the amplitude or change the sample rate to control the frequency.

 

 

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vanisri
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Re: How to create PWM pulses by comparing the sinusoidal wave with high frequency triangular wave in labview

Thank you sir,

 In my project i have to vary the frequency of triangular wave to get variable width pwm pulses. my question is can i use the sine wave and triangular wave from any wave form generation in labview or by using simulate signal block.  will you able to give any alternate suggestion?

 

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bruno_costa
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Re: How to create PWM pulses by comparing the sinusoidal wave with high frequency triangular wave in labview

Hi,

As far i know there are two frequencies on the system, first is the carrier frequencie which is the triangular wave. The second is the modulating frequency, the sinusoidal wave.

The triangular wave has a frequecy much greater than the sinusoidal wave, generally ten times the frequency of the sinusoidal wave.

If you want vary anything you should vary the sinusoidal wave, not the triangular wave.

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vanisri
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Re: How to create PWM pulses by comparing the sinusoidal wave with high frequency triangular wave in labview

Thank you sir. as per your answer i have to vary the frequency of sinusoidal wave . you are right. my question is how to implement this in labview using simulate signal block. please tell suggesstion for that.

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bruno_costa
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Re: How to create PWM pulses by comparing the sinusoidal wave with high frequency triangular wave in labview

Hi,

 

Se the code in attachment.

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wedhaaf
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Re: How to create PWM pulses by comparing the sinusoidal wave with high frequency triangular wave in labview

Hi,

I think this is what I need, but I found trouble of how to send the pulses to NI USB DAQ. Would you telling me how to do that?