Throttle control using PWM technique

[ramjimep@gmail.com]

Hi all,

I am struggling to write a LabVIEW program for controlling a throttle body (to achieve a specific mass flow rate of air). I should supply a constant frequency (500Hz) and with an appropriate pulse width (which will be converted into current) based on the air mass flow rate . The output throttle angle are two voltage signals (from potentiometer). I am yet to calibrate the throttle body and hence do not know what the pulse width should be. I am using NI USB6009.

Could someone please help me out in writing the labview code for this requirement.

Many thanks.

[apok]

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ramjimep@gmail.com wrote:

Hi all,

I am struggling to write a LabVIEW program for controlling a throttle body (to achieve a specific mass flow rate of air). I should supply a constant frequency (500Hz) and with an appropriate pulse width (which will be converted into current) based on the air mass flow rate . The output throttle angle are two voltage signals (from potentiometer). I am yet to calibrate the throttle body and hence do not know what the pulse width should be. I am using NI USB6009.

Could someone please help me out in writing the labview code for this requirement.

Many thanks.

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you have not given enough information regarding the electrical specifications you want to test? what is the voltage levels of the pulse width? what is the voltage levels of the 2 signals? is it AC/DC? is this for "work"?...tell them, they need to buy something better than a USB6009 and you can't work under these current conditions 

[ramjimep@gmail.com]

Hi Apok,

Electrical specification:

The throttle body motor is supplied with 12V. 

The feedback signal for the throttle position is an analog signal with their voltage varying between 1.9 to 5V or the resistance varying between 580 ohm to 1525 ohm.

Many thanks.

[nathand]

The 6009 is not capable of producing a reliable PWM signal at 500hz.  You need a device capable of pulse generation such as the USB-6341 (X Series).  With such a device, it is trivial to generate the pulse train you need by following the examples provided with LabVIEW.  There are likewise many examples showing how to do analog input.  If you try the sample code and cannot get it working, upload your code explaining what you tried, what you want to do, and what error or problem is occurring.

[ramjimep@gmail.com]

Hi Nathand,

Thanks for the information on USB-6009 and USB-6341.

I am still writing the program. I am totally new to LabVIEW and writing my first program.

I will post the VI once I get it reasonably good. 

Many thanks.

[ramjimep@gmail.com]

Hi All,

I have got the LabVIEW program up and running. My colleague wrote the program and works just perfect for my requirement.

I am sharing it as it would help others, especially for LabVIEW beginners like me. Thank you everyone who spent their time helping me.

In case if I need any help in the near future, I will post it.

Best regards,

Ramji