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Please help simulation synchronizing dual sin wave using PLL labVIEW



Please I want a simulation based on Lab view for synchronizing generators, as we know that the generator will generate a sin wave.


If anyone can help me with this idea the simulation can be done using to input sin waves and synchronized with each other using PLL (phase lock loop), note that the generators will be synchronized if the frequency, phase angle and voltages are equal ( synchronized). Please if somebody has simulation based on this idea to help me with it.



I will appreciate it.


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Message 1 of 11

using two input sin wave not to (corrected)

Message 2 of 11

In fact I'm also interested in PLL's


So i found this one


Keep an eye on the PID control to reach stable operation

of the loop - it's the most interesting part

Message 3 of 11

Thank you Gprogrammer for your help... but this is not my case. I want to compare frequency of two generated sin wave using the PLL and compare the rms voltage. If the differece between frequency approx. zero (maybe using zero cross method) and the voltage also the difference is approx. zero so the two generators are synchronized.Please for you help. Thank you 😞

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Message 4 of 11

Now you are confusing us. If you only want to compare frequency, phase and amplitude of two sinusoidal signals, you do not need a PLL. Just use Extract Single Tone from the Signal Processing >> Waveform Measurements palette on each signal.



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Message 5 of 11

The idea is to make a simulation that could done in real life to make a synchronizer for generators we need a PLL to synchronize the frequency. But in my case i want to synchronize two sin wave than make difference after the synchronization to assure to that the signal is synchronized. thank you i hope u understand me and dont be confused thank you 😞

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Message 6 of 11

A synchronizer or PLL has three basic components: A frequency-phase comparator or error measurement device, An oscillator (or other signal source such as the rotating mchine in the power generator situation) which can be controlled in phase or frequency, and A control system to convert the output of the comparator to the control signal necessary to change the phase or frequency of the generator.


The VIs in LV to generate sine waves have inputs to set the frequency and phase. So the requirement for a controllable source is easily met.


The phase and frequency comparison can be done several ways: Extract Single Tone Information which I mentioned earlier. You can also simulate the kinds of circuits used in hardware PLLs. These typically consist of a multiplier and a filter to implement the process modeled by the multiplication of two sine waves.  There are also curve fitting VIs.


The control process depends on many choices. How often do you measure the phase of the input signals? How much noise and interference is present? How fast do you want to update the generator phase? What kind of transient response do you want? How fast will the controlled generator change phase in the absence of a control signal? 


Is this an academic assignment? We try not to do your homework for you. We will help you understand how to use LV but the work must be yours.



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Message 7 of 11

Iam new on LV. what i want a simulation to synchronize two generators, the two generators will generate sin waves this sin waves will be compared to achieve synchronization its better to use PLL but i have no idea where to use it in this such simulation.


The below attachment will discuss more what i want but it it can be editted instead of using two generators from outside is to put to sin wave and prove that when this two sin wave are not equal so synchronization faild and vice versa.


no need for the DAQ it can be replaced by an oscilscope to see the two sine waves that are synchronized, any one can help me by this simulation 😞 i will bs very thankful for him.



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Message 8 of 11

Any help please :I

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Message 9 of 11
If I'M getting you right you want to a) Compare Two Sine Waves in Frequency and Phase via PLL This could be done if you feed these two into two equal PLL blocks and compare the Frequency Control of the two PLL internal VCOs. This is simply using PLL as Frequency Measurement building block. (Read something about PLL FM-Demodulation for instance then you'll get familiar with this concept) For the Phase Comparison you could use also the Phase Comparator that you'll find inside the PLL. The VCO outputs can also be used for generating synchronous sine signals of different frequency - this uses a frequency divider inside PLL. PLL gives you the ability to synchronize at every n* f frequency. b) Compare two sine waves in amplitude This is quite simple - isn't it? RMS or peak meters I didnt yet have tested in LabVIEW but I'm sure it'll work.
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Message 10 of 11