Gravy Boat, Custom Albin 25

How a joule thief circuit works.
https://www.youtube.com/watch?v=0GV...tHUeBthidmdYHQH9q7CDNTlDB7lDL-uqL50oYE0vd99_A

A joule thief can increase DC voltage, which can't be changed with a transformer as AC current can.

 

Ability to repair your equipment at sea is an important skill. So, understanding your equipment is a necessary prerequisite to being able to repair it. I found this video instructive. Don't intend to build this. It's instructive in recognizing the major components and functions of your inverter.
https://www.youtube.com/watch?v=tyvZGIlHEok

and this one

https://www.youtube.com/watch?feature=player_detailpage&v=6XLwVR_qBqU

Reasoning behind these posts is, solar panel charge controllers are expensive. The good ones are.
And batteries are a considerable investment if you have very many.

I'm considering the advisability of hooking solar panels directly to an inverter, with an intervening low voltage shutoff.
Battery chargers are necessary to charge from shore power, so will already be on board.
They are charge controllers, reducing to maintenance charge or shutting off when battery fully charged.
They are less expensive than solar cell charge controllers of comparable quality.

I suspect, running an inverter from solar cells and 110v battery chargers from the inverter, might be a more compact, safer for batteries, and more economical system.
You need the chargers anyway, and the inverter can equally be run from the batteries when not charging the battery.

Since the battery charger produces DC current, obviously it's rectifying and probably not sensitive to hertz. I think.
Probably won't be most efficient system, but money saved on charge controllers could be invested in bigger wattage solar panels to compensate.

Any caveats? Comments?

 

Harbor Freight panels about 4$ a watt.
Costco and Home Depot, 2$ a watt.

https://sunelec.com/

 

What's the point here?

 

quoted from my previous two posts

System A; charge controllers, inverters, battery chargers
System B; inverters, battery chargers

System B is simpler, less equipment to possibly fail, and less costly. If also less efficient, there is adequate compensation.

 

Okay! Definitive final post on the tuna can (as candle) controversy.
While the 1$ 5 oz tuna cans have no lids to fit that I can discover, the 12 oz tuna cans (1.89$) have plenty of re-purposeful candidates for fitting lids.
Lids on cashews nuts cans, and many other canned products snap on the 12 oz tuna can just perfect.
Even outfitted my bike with a SeaSwing stove, as you can see.
And the 12 oz can fits snugly inside the SeaSwing burner holder, under the pot well.

And a better price per oz on buying tuna.

My intention is to gorge myself on tuna casseroles and tuna melts and tuna salad and tuna chowder and tuna burgers (made like salmon patties or crab cakes) over the next few days until I have 6 empty cans.
http://www.caswellplating.com/elect...ing-kits/complete-baby-shoe-bronzing-kit.html

Enough to bronze 100 pairs baby shoes, or 6 large tuna cans and my 3 anchors of 3 different styles/purpose.

Just need to overcome the "non-conductive" restriction on parts to be plated.

On to next topic.
Tired of discussing tuna cans and soon will be tired of tuna, I'll bet.

http://allrecipes.com/recipe/239191/salmon-tuna-patties/
http://www.yummly.com/recipes/tuna-crab-cakes

 

I'll have these three anchors on board, but plan to push my long nose into the mud for most of my anchoring.

Mushroom Soft mud anchor, excellent piggy back for plow or Danforth in ooze. Prevents unintentional breakout.

Good dinghy anchor too.




Sand and mud. Danforth






sand, rock, weeds, and grass. Plow



http://www.boatus.org/guide/navigation_31.html

 

Probably seems confusing how I jump from topic to topic.
My excuse is: that's how my days are dis-organized.
Many aspects of the project are weather sensitive which is beyond my control.
Other aspects are dependent on cash flow and material purchase/material on hand.
Don't have immediate response to those limiters. Can't just go buy some more, if I run out. Gotta find the funds first.
Other aspects are energy sensitive. Fitting is repetitive trimming and checking for fit.
Get's exhausting when one handed supporting a fridge in an awkward tight corner.
Frequently I just run out of gas and have to do something less strenuous while my muscles recoup.
Other aspects are time sensitive.
The marina doesn't permit power tools and hammering and other rude noises at night.
Construction mostly limited to daylight hours. I can paint or clean at night, that's about it.

Anyway, I research in the evening and plan the next day, best I can.
The fridge is nearly fitted, will post photo hopefully tomorrow.

 

http://www.leonics.com/support/article2_14j/articles2_14j_en.php

"How MPPT works?
The major principle of MPPT is to extract the maximum available power from PV module by making them operate at the most efficient voltage (maximum power point). That is to say:
MPPT checks output of PV module, compares it to battery voltage then fixes what is the best power that PV module can produce to charge the battery and converts it to the best voltage to get maximum current into battery. It can also supply power to a DC load, which is connected directly to the battery.

MPPT is most effective under these conditions:
•
Cold weather, cloudy or hazy days: Normally, PV module works better at cold temperatures and MPPT is utilized to extract maximum power available from them.
•
When battery is deeply discharged: MPPT can extract more current and charge the battery if the state of charge in the battery is lowers.


MPPT solar charge controller
A MPPT solar charge controller is the charge controller embedded with MPPT algorithm to maximize the amount of current going into the battery from PV module.

MPPT is DC to DC converter which operates by taking DC input from PV module, changing it to AC and converting it back to a different DC voltage and current to exactly match the PV module to the battery.


Basics of Maximum Power Point Tracking (MPPT) Solar Charge Controller

Examples of DC to DC converter are
•
Boost converter is power converter which DC input voltage is less than DC output voltage. That means PV input voltage is less than the battery voltage in system.
•
Buck converter is power converter which DC input voltage is greater than DC output voltage. That means PV input voltage is greater than the battery voltage in system.

MPPT algorithm can be applied to both of them depending on system design. Normally, for battery system voltage is equal or less than 48 V, buck converter is useful. On the other hand, if battery system voltage is greater than 48 V, boost converter should be chosen.

MPPT solar charge controllers are useful for off-grid solar power systems such as stand-alone solar power system, solar home system and solar water pump system, etc.

Main features of MPPT solar charge controller
•
In any applications which PV module is energy source, MPPT solar charge controller is used to correct for detecting the variations in the current-voltage characteristics of solar cell and shown by I-V curve.
•
MPPT solar charge controller is necessary for any solar power systems need to extract maximum power from PV module; it forces PV module to operate at voltage close to maximum power point to draw maximum available power.
•
MPPT solar charge controller allows users to use PV module with a higher voltage output than operating voltage of battery system.
For example, if PV module has to be placed far away from charge controller and battery, its wire size must be very large to reduce voltage drop. With a MPPT solar charge controller, users can wire PV module for 24 or 48 V (depending on charge controller and PV modules) and bring power into 12 or 24 V battery system. This means it reduces the wire size needed while retaining full output of PV module.
•
MPPT solar charge controller reduces complexity of system while output of system is high efficiency. Additionally, it can be applied to use with more energy sources. Since PV output power is used to control DC-DC converter directly.
•
MPPT solar charge controller can be applied to other renewable energy sources such as small water turbines, wind-power turbines, etc."



A micro-inverter on back of PV panel converts to AC. That's part of what MPPT controller does.
Separating the panel ( via inverter) and charging circuit isolates the panel from the battery, so battery voltage isn't controlling panel, which is what MPPT does.
A good 110 battery charger provides the battery with the best charge rate current for the battery. That's something else the MPPT does.

All that's left is " it forces PV module to operate at voltage close to maximum power point to draw maximum available power"

If I can figure THIS part out, I can design and build an inverter, charger, MPPT DIY system.

Any help? Would be appreciated.

Think I got it.

http://www.solar-electric.com/mppt-solar-charge-controllers.html
"Grid tie systems are becoming more popular as the price of solar drops and electric rates go up. There are several brands of grid-tie only (that is, no battery) inverters available. All of these have built in MPPT. Efficiency is around 94% to 97% for the MPPT conversion on those'

Since they MUST match voltage and hertz/phase to the grid, they have to control the PV panel voltage with a voltage regulator. I'll look at DIY 17 volt regulator circuits.

 

Since the variable voltage is input and a constant output voltage is desired, a simple compensator circuit might be feasible.
If I hook two panels together in series, I'll get a range of a few volts in low light conditions to a maximum of 38 volts in full direct sunlight.
If a constant 24 volts were desired, a dual purpose or pair of dedicated circuits is needed.
A throttle back circuit, to reduce over voltage to 24 volts at increased amps, and a variable jewel thief circuit to enhance under voltage to 24 volts at reduced amps.

Looking for information on best types of circuits to accomplish this.

And wondering if PWM would suffice for both requirements?

Would it effectively control the voltage input to an inverter.

http://www.electronics-tutorials.ws/blog/pulse-width-modulation.html


Says you can http://www.ewh.ieee.org/soc/es/Nov1998/08/PWMINV.HTM


.

 

Yeah, it does. Still trying to surf it though ... while dodging the sharks and flotsam along the way! ;-)

 

Well, some folks claim they buy playboy for the articles and some admit it's for the pictures.
Easy to see which posts include pictures.

 

Ah, you equated picture with flotsam, etc. Not necessarily so. Picture worth a thousand words and whatnot.

 

Nope, not my intent.
I was implying that if not every post in the thread is interesting to you, I hope you find something that is.

 

OK. Well, it should be clear by now that some stuff here is interesting ... otherwise, why would I still be hanging around, right?

Speaking of that, I'm particularly interested in electric propulsion options, but just learning now ... slowing getting up to speed. Easy to be overwhelmed by either a) potential complication, b) potential cost, or both.