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Double number of pulses per cycle

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Hi ericgibbs;

I run your design expect hrpm signal. I used hall3 sensor output instead of hrpm. Also I can not used parts that made with switchs. I attached my design and simulation output.
 

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  • FreqDoubler5 (1).asc
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The sims with the switches was only posted to show you Rev and Fwd, the earlier asc files are for your sim.
What has happened to the h1,h2 and hrpm voltage source definitions.?
I cannot run your sim, where did you get those 4013 symbols/models.?

I think we are talking about a different specification.

It would be helpful if you draw and post a diagram of ALL the signals, showing the time relationship and polarity of the signals, that you expect from the final circuit design.
 
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The fact that his two signals are not truly quadrature does not change the way they work with a standard quadrature detector for direction detection and index pulsing. The 120 degree separation means that the responsiveness to direction changes will be asymmetrical, but they still will be caught with one transition of each input. My *guess* is that what the OP wants is for this to happen with 4x better resolution by frequency doubling and extracting data from both edges of the doubled freq signals. I don't think this will work because the frequency doublers need two transitions after a direction change to get back in sequence. Or something like that.

ak
 
Hi Analog.
I must admit I find the OP's specification is a little ambiguous, the circuits I have posted should satisfy most RPM sensing.?

Actually rpm of motor is 17.000; but because of safety we are using 1.5% of rpm as 225 rpm
He has geared down the revs from ~17,000 to 271, so I don't think the resolution matters.??

E
 
Hi, Les Jones,

I decided to use a phase sequence detector.Then, I designed a phase sequence detector it detects all of the rising and falling edges of hall1, hall2 and hall3. I will use output of phase sequence detector as clock. Then I will use this clock in a flip flop then I will obtain a finite state machine to determine direction of rotation. But I can not understand your advice that based on BobW's design. You said C is the clock of flip flop. Where I use output of phase sequence detector?
 
This is a diagram of the idea.

Phase_Seq.jpg

The first flipflop is set by phase A and reset by phase B. When phase C ocurres it clocks the state of the first flipflop into the second flipflop. If phase A occurres before phase B then the the first flipflop will be reset so the second flipflop will have a zero clocked into it. If phase B occurres before phase A then the first flipflop will be in the set state when phase C clocks it's state into the second flipflop into the second flipflop. So the second flipflop will now be set. You will probably have to differentiate the rising edge of each phase to get short set and reset pulses. The C phase will clock the data into the second flipflop on it's rising edge.

Les.
 
hi eng.

The circuit in post #20 gives you all the signals you need for 'rotation', 'direction' , etc.
Ignore the switches on the circuit, they are ONLY for the simulation.

I have identified two more signal points on this sim ccg and ccwg, you can see that they are gated to suit the Rev/Fwd signals, no change to the circuit.
 
The circuit below will give a clockwise, /clockwise signal.

spec

2016_11_24_Iss1_ETO_3PHASE_MOTOR_DIRECTION_DETECTOR_VER1.jpg
 
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