• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

MPPT + Voltage Doubler

ACharnley

Member
I have a spreadsheet calculating ideal voltage levels for a MPPT circuit (for a given resistance, inductance, capacitance). The figures are correct.

Given the current source is fixed I've calculated V=IR to produce the voltage levels I should drive the output to.

Questions are:

a. when using a voltage doubler it is right (assume ideal diodes) to half the current so the voltage to be driven to is double?
b. assuming non ideal diodes, is the final voltage [(a) - vDrop] or should the vDrop form part of the MPPT equation?
 

Attachments

Last edited:

dr pepper

Well-Known Member
Most Helpful Member
The op current will be less than 1/2 the ip, for several reasons, voltage dropp across the cap, Esr of the cap, vdrop in the diode.
 

ACharnley

Member
Indeed, however these are variable changing based on current draw and heat. I'll work them in if I can. The first cap(s) are ceramic based so ESR will be minimal, and the second will be large so ESR shouldn't be too high (something like 4700uF).
 

dr pepper

Well-Known Member
Most Helpful Member
I'm sure you know about low esr caps for smps's, those are the ones to go for.
For prototypes & messing ab out I salvage them from psu's, I have some dell server smps's, the quality of the parts is very good.
 

crutschow

Well-Known Member
Most Helpful Member
A capacitive voltage doubler circuit generally has low efficiency.
Better to use a boost switching converter if you are concerned about efficiency (since it's an MPPT circuit, I assume you are).
 

Beau Schwabe

Active Member
I would look into Dickson Charge Pumps also .... Personally I think they are more efficient than a typical Cascade Multiplier. Just my two cents.

Below is a link to a Video of a Dickson Charge Pump that I made awhile back ... "Excuse the miss pronunciation until the very end of the video"

 

Nigel Goodwin

Super Moderator
Most Helpful Member
I would look into Dickson Charge Pumps also .... Personally I think they are more efficient than a typical Cascade Multiplier. Just my two cents.
But not that much more efficient, the OP has been pretty vague about what he's trying to do (and why), but redesigning the complete project properly would be better than trying to bodge things with voltage multipliers. Failing that, a standard switch-mode boost converter would probably be a much better idea than multipliers.
 

Latest threads

EE World Online Articles

Loading

 
Top