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Help regarding labview model

As I am working on LAbview and I am getting some problems related to it. Some of the blocks are not in library, which are marked with black circle in the attachment. Simply I have to estimate the phasors with the help of recursive and non-recursive algorithm in LABVIEW in the attached file, nonrecursive algorithm have been used where,A 50-Hz signal x(t)=230 cos (120*pi*t+pi/4) is sampled at a frequency of 600 Hz i.e. 12 samples per cycle are taken. First 20 samples are obtained and phasor estimate through recursive and nonrecursive are evaluated. The data window is of 12 samples. Since phasor estimation is performed over a cycle, the first phasor is obtained after obtaining 12 samples i.e. after one complete cycle of the sinusoid.  The phasor output in polar form for recursive and nonrecursive estimates as obtained from Labview front panel as shown in attachment.

The input signal can be generated from library VI i.e. Simulate Signal VI. This signal can also be real time acquired from a data acquisition system like NI ELVIS which is compliant with Labview. This analog input signal is then converted to discrete signal with A2D VI and stored in an array. Here data window is considered for 12 samples. A user defined VI has to be prepared for calculating the Fourier coefficient of the data samples. Appropriate arithmetic operations are performed to estimate phasor for first data window. The complex term obtained after phasor calculation is converted into polar form and displayed as output. This algorithm is repeated for subsequent data samples.



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Message 1 of 19
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As I am working on LAbview and I am getting some problems related to it. Some of the blocks are not in library, which are marked with black circle in the attachment. Simply I have to estimate the phasors with the help of recursive and non-recursive algorithm in LABVIEW in the attached file, nonrecursive algorithm have been used where,A 50-Hz signal x(t)=230 cos (120*pi*t+pi/4) is sampled at a frequency of 600 Hz i.e. 12 samples per cycle are taken. First 20 samples are obtained and phasor estimate through recursive and nonrecursive are evaluated. The data window is of 12 samples. Since phasor estimation is performed over a cycle, the first phasor is obtained after obtaining 12 samples i.e. after one complete cycle of the sinusoid.  The phasor output in polar form for recursive and nonrecursive estimates as obtained from Labview front panel as shown in attachment.

The input signal can be generated from library VI i.e. Simulate Signal VI. This signal can also be real time acquired from a data acquisition system like NI ELVIS which is compliant with Labview. This analog input signal is then converted to discrete signal with A2D VI and stored in an array. Here data window is considered for 12 samples. A user defined VI has to be prepared for calculating the Fourier coefficient of the data samples. Appropriate arithmetic operations are performed to estimate phasor for first data window. The complex term obtained after phasor calculation is converted into polar form and displayed as output. This algorithm is repeated for subsequent data samples.



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Message 2 of 19
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Hi Alok,

 

please don't create double posts in different threads, especially when you forget to add attachments!

 

I moved your 2nd message into this thread…

Best regards,
GerdW


using LV2016/2019/2021 on Win10/11+cRIO, TestStand2016/2019
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Message 3 of 19
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This is the attachment

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Message 4 of 19
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Hi Alok,

 

the big black icons are custom-made VIs. Ask the one who created that block diagram.

 

The other encircled functions are BuildArray and IndexAndBundleClusterArray…

Best regards,
GerdW


using LV2016/2019/2021 on Win10/11+cRIO, TestStand2016/2019
Message 5 of 19
(4,545 Views)

Hello sir.. 

 

Sir in this I am getting magnitude with angle but i am getting only 1 value. I am not getting the same magnitude and angle should be progressed by 30 degree. Magnitude is shown in block (array of clusters) coming 162.635 with the angle 45 degree but i am not getting all values

not getting this
162.635∠45°
162.635∠75°
162.635∠105°
162.635∠135°
162.635∠165°
162.635∠-165°
162.635∠-135°
162.635∠-105°
only getting single first value

and i also want to know the time taken to find out the non-recursive updates as shown in block array of clusters.

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Message 6 of 19
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If you talk about mangitude, angle, value, etc. it would help to change the label of the various controls so they correspond to the meaning.

 

In any case, your express VI is configured to reset with every call. Configure it for "continous generation" instead and also slow down the loop rate so you can actually see what's happening.

 

Message 7 of 19
(4,351 Views)

Respected sir,

But I want to see the results with each and every value. I want individual Ans like this.

162.635∠45°
162.635∠75°
162.635∠105°
162.635∠135°
162.635∠165°
162.635∠-165°
162.635∠-135°
162.635∠-105°

So please tell me how will I can get these values, So that each of these values are visible.

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Message 8 of 19
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I am getting only three values i.e.

162.635∠45°
162.635∠-75°
162.635∠-165°

these are wrong. I need these values

162.635∠45°
162.635∠75°
162.635∠105°
162.635∠135°
162.635∠165°
162.635∠-165°
162.635∠-135°
162.635∠-105°

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Message 9 of 19
(4,333 Views)

If you need different values for the incremental phase, you need to change the parameters of the signal. Figure it out: The starting phase of the next wave is wherever the previous wave ended, so the fractional part of the period is important.

 

You've been working on this now for weeks making basically no progress. Just do the math and the rest will fall into place. It seems you want a 30 degree increment, so each single wave should be N+1/12 periods.

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Message 10 of 19
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