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Thread: POCO issue or not?

  1. #21
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    190615-2216 EDT

    Consider the general concept of a voltage regulator.

    This a device that in some way can adjust its output voltage based upon the measured output voltage at some output point. This can and usually is local at the regulator output terminals. But there are many DC regulators with remote sense capability. This means one can do the regulation operation such that the voltage at the remote location is what is regulated.

    To a large extent within some limited range this means that the apparent source impedance of the regulator is much lower than the source impedance of the power input to the regulator.

    Suppose you had a DC regulator that could hold output within 10 mV with a load change of 1 A, then the apparent small signal regulator output impedance is Z = 0.01/1 = 0.01 ohm. For some applications this could be approximated as zero source impedance.

    Next consider a substation with voltage regulation. From the substation to users there is line and transformer impedance. A power consuming load will lower the voltage at the load point.

    Next consider power generators as the load, solar panels. This means there is a rise in voltage from those generators near the generators. This rise will be greater than the drop from other loads when demand from power consumers is lower than power from the generators. Likely with a lot of solar some time after sun rise. So voltage away from the substation at the load end may go above the regulated value at the substation.

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  2. #22
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    Good summary gar.
    BB+/BB=?

  3. #23
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    190616-2132 EDT

    With most areas now having smart meters installed, and assuming that the power company can get voltage information from the meters, then it should be possible to get some remote voltage measurements that could be used in the voltage regulator feedback loop.

    In my general neighborhood area I know of no PV arrays. Around Ann Arbor there are a number of large DTE PV arrays. One on North Campus is https://www.google.com/maps/@42.3022...thumbfov%3D100

    A new large substation is being built on North Campus within 1/2 mile of the array. This new substation is in addition to another that is a couple miles away, and the combination provides redundant power supply. This is also backed up by multi-megawatts of various diesel generators. There are critical projects on the North Campus that require relatively uninterrupted power. There is also some North Campus steam generation, and of course the Main Campus power plant.

    Thus, North Campus has good redundancy.

    In the microcircuits lab they also produce extremely pure water, and have extremely clean air.

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