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## how to find the area under the graph .... cant solve !!!

Hello everyone. I am a year 3 student of EE and i am doing a final year project about state of charge of lithium ion battery.

Now i want to know the capacity of battery discharged so i develop a program and a current adjust button to adjust the dischrage current.

But here is a problem. I dont know how to find the area of the graph under the dischage current against time.

Can anyone help me plz ??

Message 1 of 6
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## Re: how to find the area under the graph .... cant solve !!!

You would just integrate your data, there's a VI for that. 🙂

What is the datatype of your curve (array, waveform, dynamic, etc.)?

Can you attach a simplified version of your actual VI and some data?

LabVIEW Champion. It all comes together in GCentral
What does "Engineering Redefined" mean??
Message 2 of 6
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## Re: how to find the area under the graph .... cant solve !!!

actually i use GPIB card to link the load and the computer together, so i cant give a simplified verison for u.

But the full version is still easy to read .

I use a bundle to combine the the two readings together.

Message 3 of 6
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## Re: how to find the area under the graph .... cant solve !!!

Hi,

as the plots looks like a bar plot you may simply use the formula "sum(I*dt)" (which is a simplified form of integration).

But as a "year 3 student of EE" you should have heard that before

Best regards,
GerdW

using LV2011SP1 + LV2017 (+LV2020 sometimes) on Win10+cRIO
Message 4 of 6
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## Re: how to find the area under the graph .... cant solve !!!

yes i know i * dt but as the discharge current changes, i dont want the time to accumulate with the previous discharge current time. That 's why it annoy me a lot and i dont know how to use those integration vi  as those need a waveform input but in my program the waveform is just a bundle of current and voltage. Can i still use the vi  to do that ??

Message 5 of 6
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## Re: how to find the area under the graph .... cant solve !!!

Hi there,

You can split the data into several parts, and bundle the data to waveform datatype and use integral vis in LV to fulfill the job.

NISH AE

Fortune

Message 6 of 6
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