is a MOSFET required to reduce heat???? - Page 1
Forum section: electronics / beginners

author: magnetman12003
author_rank: Contributor
timestamp: June 21, 2016, 04:30:54 am
content: I have made the below pancake coil device and it works. Can someone suggest a way to replace the TIP 35C transistor and heat sink so there is no wasted heat loss. Someone suggested using a IRFZ30 Mosfet transistor.If that works do I still need a resistor or a heat sink?? I would like to make this as SIMPLE, cool running ,efficient,as possible. Circuit illustration will be a big help.This is what I have constructed.

author: Signal32
author_rank: Frequent Contributor
timestamp: June 21, 2016, 05:00:08 am
content: In your specific schematic you can certainly not replace the transistor with a MOSFET. It will absolutely not work.There are designs that use MOSFETs likehttp://www.instructables.com/id/Wireless-Ipod-Charger/?ALLSTEPSbut that one still doesn't avoid the issue of dissipating power into the MOSFETs.I'm actually curious if someone can point out a design with minimal power loss such that it will work efficiently over multiple distances, I'm thinking you will need a micro to be able to do this.

author: ataradov
author_rank: Super Contributor
timestamp: June 21, 2016, 05:07:14 am
content: Use a separate frequency generator to control the transistor.In your circuit transistor is in a linear region most of the time. Changing it to MOSFET and controlling it though an MCU will eliminate heating. You will need a feedback coil so MCU could intelligently control the MOSFET. There is no need to make feedback coil as big as the main one, it is just a waste of copper.Edit: it will eliminate heating of the transistor, there is still going to be energy loss in the coil, but it is big enough, so it will dissipate it efficiently.

author: alsetalokin4017
author_rank: Super Contributor
timestamp: June 21, 2016, 05:20:16 am
content: Of course you could use a different type of oscillator instead of the "Joule Thief" architecture. For example a mosfet-based ZVS oscillator will not waste much power in the mosfets. It will have a few more components and will waste some power in heating them, but the mosfets themselves should stay cool if the circuit is properly constructed.

author: magnetman12003
author_rank: Contributor
timestamp: June 21, 2016, 03:50:15 pm
content: Quote from: alsetalokin4017 on June 21, 2016, 05:20:16 amI need a illustrated circuit as a reference to follow. Having solved that problem the device I am making with the pancake coils should self charge the 12 volt battery that's powering the circuit and the circuit may sustain itself.That's wishful thinking but I am giving it a go. Already had the circuit working for 5 straight hours but not enough current for battery charging so I thought about using pancake coils as in the video.

author: ataradov
author_rank: Super Contributor
timestamp: June 21, 2016, 04:05:05 pm
content: Have you done any calculations at all? "Giving it a go" is not very scientific.

author: suicidaleggroll
author_rank: Super Contributor
timestamp: June 21, 2016, 04:13:10 pm
content: Quote from: magnetman12003 on June 21, 2016, 03:50:15 pmNo, it won't.

author: Mechatrommer
author_rank: Super Contributor
timestamp: June 21, 2016, 04:31:50 pm
content: duh we have over unity believer... you have any clue why the transistor went that hot in your setup? have you any idea the efficiency we are talking about here?

author: HighVoltage
author_rank: Super Contributor
timestamp: June 21, 2016, 04:57:45 pm
content: Even if you had zero wasted heat loss at your transistor, you could not charge your batteries for free.Oh, Oh, another free energy thread from someone that does not understand the basics.

author: magnetman12003
author_rank: Contributor
timestamp: June 21, 2016, 06:26:17 pm
content: Quote from: suicidaleggroll on June 21, 2016, 04:13:10 pmThat's interesting as even with less than .10 amps of current flowing I had my "ORIGINAL"unpublished circuit running for 5 straight hours.Now it should do even better using pancake coils. How better is to be found out by trying.

author: ataradov
author_rank: Super Contributor
timestamp: June 21, 2016, 06:28:42 pm
content: Ok, I'll bite.Quote from: magnetman12003 on June 21, 2016, 06:26:17 pmFlowing where?Quote from: magnetman12003 on June 21, 2016, 06:26:17 pmWasting a lot of energy in the process? There are a lot of circuit that run for more than 5 hours, so what?

author: MK14
author_rank: Super Contributor
timestamp: June 21, 2016, 06:38:24 pm
content: Quote from: magnetman12003 on June 21, 2016, 06:26:17 pmIt is generally believed that you need to get energy from SOMEWHERE. You CAN'T just create free energy.Sorry!For some reason, you DON'T seem to be getting the message ?EDIT:To put it another way.Can you take half a glass of milk, and manipulate it in some way. Resulting in a FULL glass of milk. Effectively getting an unlimited/free source of milk for life ?

author: suicidaleggroll
author_rank: Super Contributor
timestamp: June 21, 2016, 06:44:10 pm
content: Quote from: magnetman12003 on June 21, 2016, 06:26:17 pmSo? What's your point? That's the purpose of batteries, to power circuits, sometimes for several hours or even days.And is this the same ammeter that you were using inthisthread where you mistook the out of range error indicator as a measurement of 1 amp, took that to mean your piddly little fan was drawing 300 watts, and then tried to sell the POS device for $10k?

author: magnetman12003
author_rank: Contributor
timestamp: June 21, 2016, 06:58:55 pm
content: Quote from: suicidaleggroll on June 21, 2016, 06:44:10 pmI am not selling anything and so far no one has posted any schematic diagram of any sort. Forget free energy talk - did I ever mention that here? All I am looking for now is EFFICIENT use of a single transistor to power what I have made. That's all.

author: ataradov
author_rank: Super Contributor
timestamp: June 21, 2016, 07:02:35 pm
content: If you are looking for efficiency, then there is no "simple". But then again, you need to define "efficiency" here and what is your actual goal. Not heating the transistor is relatively easy. Achieving good energy transfer with air core transformer is way harder.

author: suicidaleggroll
author_rank: Super Contributor
timestamp: June 21, 2016, 07:06:05 pm
content: Quote from: magnetman12003 on June 21, 2016, 06:58:55 pmYes, right here:Quote from: magnetman12003I'm afraid I can't give you a schematic for optimizing the drive circuit for the coil, but perhaps somebody else here can.

author: suicidaleggroll
author_rank: Super Contributor
timestamp: June 21, 2016, 07:07:34 pm
content: Quote from: MK14 on June 21, 2016, 06:38:24 pmOf course, just pour it into a smaller glass!

author: MK14
author_rank: Super Contributor
timestamp: June 21, 2016, 07:12:30 pm
content: Quote from: suicidaleggroll on June 21, 2016, 07:07:34 pmGood answer!But you CAN do it in real life. Proof:

author: Mechatrommer
author_rank: Super Contributor
timestamp: June 21, 2016, 07:25:27 pm
content: Quote from: magnetman12003 on June 21, 2016, 06:58:55 pmfree energy as in wind turbine is doable. over unity is something else. claim of self sustaining electric circuit is a different league of game.btw, do you have oscilloscope to see the current changes when you change your wireless load? can you do 5 hours using the same motor in the video? if you cant give a clear figure on your circuit's efficiency or any other sensible spec, then i'm afraid you dont have anything as reliable claim as even a "nearly self sustaining circuit". interesting project btw, anybody with enough free time may improve the circuit for you, but if the objective is a self sustaining circuit, it is a clear delusional attempt. you may choose to realize it the quick way here in this forum, or the slow way through your own venture...you need to understand to improve it, one need to understand whats going on in the magnetic field of the transistor's base node, make few measurements and probing, not a single eyeballing your video and find an optimized solution on the first try. but lets hope somebody around here have done similar project and present to us the optimized circuit in silver plater. but over unity? no!

author: System Error Message
author_rank: Frequent Contributor
timestamp: June 22, 2016, 01:34:11 am
content: traditional transformer layout has a physical isolation from mains.a joule thief works on a low voltage and converts it to a much higher voltage, unsuitable for projects that require a lot of amps.using a Mosfet with a transistor and stuff means you can use a smaller transformer because it does thing by switching instead. My router's PSU which is internal and not in a plug uses this and temperature is actually important so it is a good idea to add heatsinks to the transistor, mofset and so on.

author: McBryce
author_rank: Super Contributor
timestamp: June 22, 2016, 01:29:55 pm
content: Quote from: MK14 on June 21, 2016, 06:38:24 pmYes, but I need a further component, known as "a cow"McBryce.

author: alsetalokin4017
author_rank: Super Contributor
timestamp: June 22, 2016, 02:21:17 pm
content: Quote from: magnetman12003 on June 21, 2016, 06:58:55 pmTry this ZVS driver circuit:

author: Zero999
author_rank: Super Contributor
timestamp: June 22, 2016, 02:48:47 pm
content: Quote from: suicidaleggroll on June 21, 2016, 07:06:05 pmUnless he was talking about using the coil for harvesting energy from somewhere else.

author: MK14
author_rank: Super Contributor
timestamp: June 22, 2016, 02:59:06 pm
content: Quote from: McBryce on June 22, 2016, 01:29:55 pmOk, I did not write the original analogy well enough, to stop it being disproved by using different sized glasses, cows (or wives pair refill etc), refilled from bottles/cartons, etc.I suppose you could even use coconut milk (if your country is suitable), which grows on trees.

author: System Error Message
author_rank: Frequent Contributor
timestamp: June 23, 2016, 02:25:34 am
content: Is there any health hazard to have one capable of providing wireless electricity for 100M of range?

author: ataradov
author_rank: Super Contributor
timestamp: June 23, 2016, 02:29:24 am
content: Quote from: System Error Message on June 23, 2016, 02:25:34 amWell, so far no one was able to create anything capable of doing even 1 m. If you just go for it in a dumb way and make something really-really powerful, then yes, there is health hazard.Thankfully it is very expensive to do, and alternative energy people are very poor.