Introduction: A Variable Power Supply With Variable Current Adjustment

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***********/ PLEASE EXCUSE THE FINAL PRODUCT AND THE PRESENTATION AS IT CANT BE MADE WHAT I IMAGINED BCOZ OF SOME REASONS AND IF YOU ARE MAKING IT PLZ MAKE A GOOD ENCLOUSRE FOR IT AS IT WILL LOOK GOOD/************


one of the best videos on this topic and inspiration for this - https://youtu.be/R354-DzTkvI

so this is a variable power supply with current limiting feature you can get output at any voltage unlike others where you have a predefined voltage given there are two potentiometer given to control the volt and the current

which can be used to charge various packs of li ion cells because it has CC/CV function.


Supplies

THE MAIN THINGS NEEDED TO MAKE IT-

  1. A mains AC to 24v DC converter
  2. a 150 w boost converter
  3. a 300 w buck converter with cc / cv compatibility

Step 1: Taking a Look at the AC to DC Module (full Bridge Rectifier)

ok so this is the second most important component of our project what this does is basically takes you mains 230v AC power and converts it into 24v DC using full bridge rectifier and other filters like capacitors

this module can output up to 6A that's why this is chosen as it can give out a lot of power

you can use a power supply that suits your need just keep the output under 32v dc (will discuss ahead)

Step 2: The Boost Needed (optional)

ok so the next step is to add a boost converter *note - keep this component a bit beefy so that it can handle a lot of power

now keep in mind this is not magic the power in and out is same as when it steps up the DC voltage it reduces the current in proportion but that shouldn't bother us

now why is this optional-

this is used to step up the voltage from 24v to 31 volts the reason being out buck converter (main module) has an upper limit of 32v so why not push it till there as its a buck converter so it will only step down the voltage from the one that is give............ so if you directly power it it can output variable voltages below 24v only


but if you use this module to power it you get an extra room for some tasks so now you get variable voltages below 31v

look at the datasheet for more info.

Step 3: BUCK Converter (THE HEART)

this is the buck converter rated for 300 watts this is the heart of our project as this supports cc/cv and that's what we need it has got 2 potentiometer one for voltage and other for current we have to de solder the default potentiometer and change it with the more conventional one to give better access as these need screw drivers to change the value


look at the datasheet for more info.

Step 4: The Volt/Amp Meter

this is the volt amp meter this is used to show additional information like output voltage , current , and total wattage

in the above pictures the second one is the most commonly available and used but if can get hands on the first one which has a wattage reading its a good deal but the wing for both is same

watt = volt*current that's all the first one has.

Step 5: The Circuit Diagram

the upper photo is the circuit diagram for this project keep in mind the thickness of the wire and keep min mind the polarity we are working with DC voltage and

check this video by 'Hi I Make it' will make the wiring more clear - https://youtu.be/R354-DzTkvI

Step 6: Potentiometer

ok so the potentiometers given on the modules are for varying the voltages and current so grab your multimeters and hook the probes to the output of the boost module then slowly rotate the potentiometer in clockwise direction if you see the voltage rising stop when it reaches or shows 31.5v in your multimeter if it appears to step down then just simply rotate it counter clockwise


leave the buck converter as its anyway gonna use external potentiometer.

Step 7: Last

wire everything up as shown in the diagram and make a enclosure for you project and now you have your vary own power supply enjoy . the product purchase link maybe added in the future.

this power supply can be used for various purposes like powering your projects while prototyping or powering some tools , charging li ion or li polymer cells and battery pack . so it has a lot of use case

*THE PRODUCTS ARE FIUND ON A LOT OF WEBSITES DEPENDING ON REGION SO ITS A BIT DIFFICUT TO SHARE THE BUYING LINKS SO PLEASE LOOK AT THE PHOTO WISELY*

THANKS. some videos which may give you better ideas -

1) https://youtu.be/R354-DzTkvI

2) https://youtu.be/wI-KYRdmx-E

3) https://youtu.be/-t1wiGrxB2E

4) https://youtu.be/PhLFmokgr9o

5) https://youtu.be/PhLFmokgr9o


THANKS,