Power regulation on a voltage regulator

[Scott Ronald]

Hi
I have a working programmable voltage regulator, and I want to add a
power regulation loop that feeds the voltage regulation vref. I am
currently reading in the current and voltage by ADCs.

My idea for the power regulator inputs are:
Vmax = the maximum voltage to regulate to (constant)
Iadc = the current on the output of the voltage regulator
Vadc = the voltage on the output of the voltage regulator
P = Iadc * Vadc
Pref = the constant desired power output
Gain = the constant adjustable gain

I am guessing I cannot simply calculate the voltage like this:

Vreg = (Pref - P) * gain
if(Vreg > Vmax)
{
Vreg = Vmax
}

This will not work because power and voltage have different dimensions?

How do you do this?

Scott

 

[MooseFET]

Hi
I have a working programmable voltage regulator, and I want to add a
power regulation loop that feeds the voltage regulation vref.  I am
currently reading in the current and voltage by ADCs.

My idea for the power regulator inputs are:
Vmax = the maximum voltage to regulate to (constant)
Iadc = the current on the output of the voltage regulator
Vadc = the voltage on the output of the voltage regulator
P =  Iadc * Vadc
Pref = the constant desired power output
Gain = the constant adjustable gain

I am guessing I cannot simply calculate the voltage like this:

Vreg = (Pref - P) * gain
if(Vreg > Vmax)
{
   Vreg = Vmax

}

This will not work because power and voltage have different dimensions?

How do you do this?

Are your settings constant?

I assume you want to do something like this only without looping and
incrementing.

if ((Iout*Vout) < Pmax) and (Vout < Vmax)
Increase Vout

if ((Iout * Vout) > Pmax)
Decrease Vout


If this is what you want, there is a little more information needed
about the nature of the load. If the load is a very large capacitor
or a zener diode or the like, it is a much different problem than if
it is resistive.