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CognitiveNet
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My professor in Feedback Control Systems told me that a lead-lag compensator is basically a low pass filter and that you can't amplify high frequencies because it requires a lot of energy. Thus, you can't design a PID/lead-lag compensated transfer function which acts like a bandpass filter. Is this correct?
Based on this assumption, I've come up with a theory: In my laboratory, I've built an infrared transmitter and receiver with an RLC as its bandpass filter. The receiver isn't working and no other engineers have been able to make it work. So according to what my professor told me, is this because the power supplied isn't sufficient? (If the voltage was any higher, the op-amps would burn up.)
The circuit is shown in the website bellow;
http://howcircuits.com/active-ir-motion-detector.html
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I recently discovered something interesting that might support what my professor stated:
"If you attempt to set ωCO1 to a higher frequency than ωCO2, the band-pass filter will block all frequencies, and no signal will get through."
http://www.play-hookey.com/ac_theory/band_pass_filters.html
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Another proof that he is right:
The lead compensator offers PD control. This causes it to speed up the response of a system.
With a lead compensator high frequencies are amplified.
The PI controller reduces high-frequency
noise. As such, it can be used as a low-pass filter
The lead-lag compensator combines the lead and the lag compensator.
http://aerostudents.com/files/automaticFlightControl/adjustingSystemProperties.pdf
So from this I assume it is just a compensated low-pass filter.
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Based on this assumption, I've come up with a theory: In my laboratory, I've built an infrared transmitter and receiver with an RLC as its bandpass filter. The receiver isn't working and no other engineers have been able to make it work. So according to what my professor told me, is this because the power supplied isn't sufficient? (If the voltage was any higher, the op-amps would burn up.)
The circuit is shown in the website bellow;
http://howcircuits.com/active-ir-motion-detector.html
-----------------------------------------------------------------
I recently discovered something interesting that might support what my professor stated:
"If you attempt to set ωCO1 to a higher frequency than ωCO2, the band-pass filter will block all frequencies, and no signal will get through."
http://www.play-hookey.com/ac_theory/band_pass_filters.html
-----------------------------------------------------------------
Another proof that he is right:
The lead compensator offers PD control. This causes it to speed up the response of a system.
With a lead compensator high frequencies are amplified.
The PI controller reduces high-frequency
noise. As such, it can be used as a low-pass filter
The lead-lag compensator combines the lead and the lag compensator.
http://aerostudents.com/files/automaticFlightControl/adjustingSystemProperties.pdf
So from this I assume it is just a compensated low-pass filter.
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