# Time period between rising edeges of a signal

Discussion in 'Homework Help' started by keerthanagovind, Apr 17, 2015.

1. ### keerthanagovind Thread Starter New Member

Apr 17, 2015
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0
Hi..I need to do a project for my M.tech.I am using PSIM 9.0.3 for my simulation.In my project, I have to find time period between rising edges of a signal inorder to calculate the speed of a BLDC motor using the equation w=20/(P*t).How do i find the same?Thanks in advance

2. ### MikeML AAC Fanatic!

Oct 2, 2009
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What are you allowed to use for your project?

3. ### WBahn Moderator

Mar 31, 2012
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Are you able to successfully run the simulation?

How are you supposed to find the period? Manually? Using formulas in the simulator?

4. ### keerthanagovind Thread Starter New Member

Apr 17, 2015
3
0
Thats where i need help.I cant find a way to measure the time period.

Sorry sir.I didn't get you.Could yoy please make it more clear?

I am not able to complete my circuit without speed calculation.So i am really in need to measure time period.

Last edited by a moderator: Apr 18, 2015
5. ### WBahn Moderator

Mar 31, 2012
18,088
4,917
There are many ways to measure the time period. You can simply look at the display of the waveform and write down what the times are for successive rising edges and then use a calculator to compute the period. Or you can include a microcontroller in your circuit that digitizes the waveform and then run a program that determines the period. Or well over a dozen other methods in between those extremes. You aren't giving us enough information on what your requirements are to be able to offer much assistance.

What "circuit" is it that you are trying to complete?

6. ### keerthanagovind Thread Starter New Member

Apr 17, 2015
3
0
I am trying to do current source inverter fed buck type brushless dc motor.I am using sensorless method for position estimation.So to find out speed in my reference paper the author has suggested to measure time period ts between rising edges of signal and use the above equation.So i need to know how to find the time period between rising edges of a signal while doing simulation in psim.

Thank youSir,But I am trying to do the project in software and not in hardware initially. is the above method possisible in that case?

Last edited by a moderator: Apr 18, 2015
7. ### t_n_k AAC Fanatic!

Mar 6, 2009
5,448
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PSIM has a configurable & resettable up/down counter function.
This, along with a few other functions, may be put to use for waveform period measurement.