Naked Science Forum

On the Lighter Side => Science Experiments => Topic started by: hamdani yusuf on 30/03/2022 11:40:06

Title: How does induction heater work?
Post by: hamdani yusuf on 30/03/2022 11:40:06
How does induction heater work? This video can provide a starting point for us to understand the device better.
Quote
In this video I will show you how a common induction heater works, what kind of materials it can heat up and how you can easily create your own.

I've got a cheap ZVS (zero voltage switch) induction heater to explore its behavior. It has 120W maximum power, and working at 5-12VDC. I've tested its functionality, and I'm planning to investigate further on its characteristics, and how it reacts to different things.
Title: Re: How does induction heater work?
Post by: Bored chemist on 30/03/2022 12:41:05
How does induction heater work?
By induction.
Title: Re: How does induction heater work?
Post by: hamdani yusuf on 30/03/2022 15:21:43
How does induction heater work?
By induction.
How do its effectiveness and efficiency change with changes of following parameters?
Working frequency
Working Voltage
Working current
Inductance of the coil
shape of the coil
size of the heated material
shape of the heated material
substance of heated material
Title: Re: How does induction heater work?
Post by: hamdani yusuf on 30/03/2022 15:30:42
I've got a cheap ZVS (zero voltage switch) induction heater to explore its behavior. It has 120W maximum power, and working at 5-12VDC. I've tested its functionality, and I'm planning to investigate further on its characteristics, and how it reacts to different things.
Commercial induction cookers have safety equipment in it, which limits our usage to explore its behaviors in various circumstances. The electronic kit that I use here has no such thing, which is more preferred. But it also poses risk of breaking the components, especially the transistors. I burnt them down previously when the heating coil was disconnected from the circuit.
Title: Re: How does induction heater work?
Post by: hamdani yusuf on 14/04/2022 09:25:10
 
I've got a cheap ZVS (zero voltage switch) induction heater to explore its behavior. It has 120W maximum power, and working at 5-12VDC. I've tested its functionality, and I'm planning to investigate further on its characteristics, and how it reacts to different things.
I've done recording some experiments using the induction heater. I got some interesting results which I'd like to share here. The heated objects are mostly ferrous materials. Different shapes, orientation, and position of object around the heating coil affect the heating power, which is measured using clamp Ampere meter and thermal camera.
Title: Re: How does induction heater work?
Post by: Bored chemist on 14/04/2022 10:52:36
How does induction heater work?
By induction.
How do its effectiveness and efficiency change with changes of following parameters?
Working frequency
Working Voltage
Working current
Inductance of the coil
shape of the coil
size of the heated material
shape of the heated material
substance of heated material

In a very complicated way.
Title: Re: How does induction heater work?
Post by: hamdani yusuf on 17/04/2022 00:07:32
Quote
https://en.m.wikipedia.org/wiki/Induction_heating
An induction heater consists of an electromagnet and an electronic oscillator that passes a high-frequency alternating current (AC) through the electromagnet. The rapidly alternating magnetic field penetrates the object, generating electric currents inside the conductor, called eddy currents. The eddy currents flow through the resistance of the material, and heat it by Joule heating. In ferromagnetic and ferrimagnetic materials, such as iron, heat also is generated by magnetic hysteresis losses.
A thin steel wire or a needle at the axis of heating coil is unlikely to generate significant eddy current. Most heat would be generated by magnetic hysteresis losses. Is the heating power affected by wire length?
Title: Re: How does induction heater work?
Post by: hamdani yusuf on 25/04/2022 15:40:57
I've got a cheap ZVS (zero voltage switch) induction heater to explore its behavior. It has 120W maximum power, and working at 5-12VDC. I've tested its functionality, and I'm planning to investigate further on its characteristics, and how it reacts to different things.
Commercial induction cookers have safety equipment in it, which limits our usage to explore its behaviors in various circumstances. The electronic kit that I use here has no such thing, which is more preferred. But it also poses risk of breaking the components, especially the transistors. I burnt them down previously when the heating coil was disconnected from the circuit.

Here's my introduction to the mini ZVS induction heater I will use to conduct the experiments.

Title: Re: How does induction heater work?
Post by: hamdani yusuf on 29/04/2022 07:09:35
Here are some videos of experiments I've done investigating the work of induction heater.
The first one investigate the heating profile of the heating circuit itself, and some objects with different shapes.


The second video investigates further with the induction heating of various objects.

Title: Re: How does induction heater work?
Post by: hamdani yusuf on 05/05/2022 03:09:14
This experiment shows induction heating of a steel wire with various shape and orientation.


Compare it with a copper cable.


Axially oriented steel wire generates heat while copper wire doesn't. In this case, the heat is generated by magnetic hysteresis losses instead of eddy current.

Quote
https://en.wikipedia.org/wiki/Induction_heating
An induction heater consists of an electromagnet and an electronic oscillator that passes a high-frequency alternating current (AC) through the electromagnet. The rapidly alternating magnetic field penetrates the object, generating electric currents inside the conductor, called eddy currents. The eddy currents flow through the resistance of the material, and heat it by Joule heating. In ferromagnetic and ferrimagnetic materials, such as iron, heat also is generated by magnetic hysteresis losses.

Another notable result is that steel wire coil doesn't generate much heat. This fact should give us a clue to improve our understanding about magnetism.
Title: Re: How does induction heater work?
Post by: hamdani yusuf on 23/05/2022 14:02:38
This experiment shows the induction heating of permanent magnets. It seems that magnetic hysteresis losses are not that significant here.
Title: Re: How does induction heater work?
Post by: Rodneyhhernandez on 23/05/2022 23:55:49
An induction heater consists of an electromagnet and an electronic oscillator that passes a high-frequency alternating current (AC) through the electromagnet.
Title: Re: How does induction heater work?
Post by: hamdani yusuf on 24/05/2022 03:49:54
An induction heater consists of an electromagnet and an electronic oscillator that passes a high-frequency alternating current (AC) through the electromagnet.

I did some measurements on the device I used here.

I've got a cheap ZVS (zero voltage switch) induction heater to explore its behavior. It has 120W maximum power, and working at 5-12VDC. I've tested its functionality, and I'm planning to investigate further on its characteristics, and how it reacts to different things.
Commercial induction cookers have safety equipment in it, which limits our usage to explore its behaviors in various circumstances. The electronic kit that I use here has no such thing, which is more preferred. But it also poses risk of breaking the components, especially the transistors. I burnt them down previously when the heating coil was disconnected from the circuit.

Here's my introduction to the mini ZVS induction heater I will use to conduct the experiments.

Title: Re: How does induction heater work?
Post by: hamdani yusuf on 27/05/2022 12:13:10
Demonstration of induction heating steel wire with various cut length.
Title: Re: How does induction heater work?
Post by: hamdani yusuf on 28/05/2022 05:45:33
Demonstration of induction heating short steel wires
Title: Re: How does induction heater work?
Post by: hamdani yusuf on 28/05/2022 06:48:12
Before I continue with my experiments, I want to share a video containing important information to understand about eddy current.
Title: Re: How does induction heater work?
Post by: hamdani yusuf on 30/05/2022 03:32:18
In non-ferrous materials, there's no significant heat is generated by magnetic hysteresis losses. The heat is mainly produced by eddy current.
Title: Re: How does induction heater work?
Post by: hamdani yusuf on 07/06/2022 03:17:53
Here's a video showing induction heating of broad metal plates.
It shows that the field outside of the coil is much weaker than the inside.
We can see how plate thickness affects the difference in power consumptions between when the plate is at the end of heating coil and the middle of the coil. My hypothesis for this, is that the thin plate of cutter knife was already saturated by the magnetic field at the edge of the coil. Stronger magnetic field at the middle doesn't add much to the power consumption.
Title: Re: How does induction heater work?
Post by: hamdani yusuf on 07/06/2022 03:31:03

Here's a video of induction heater involving a ferrite rod.
The first interesting thing we can find is that the insertion of ferrite rod can reduce total power consumption, even though it absorbs some energy and generate heat. To do that, it must have taken the energy from somewhere else, e.g. the energy that was previously spread to the surrounding of the coil.
Title: Re: How does induction heater work?
Post by: hamdani yusuf on 30/05/2023 14:59:50
The recordings here were taken not long after the last video, but I only finished the editing and uploading just now.
In this video I continued experimenting on Eddy current using an induction heater.
It shows that a ferrite rod and a steel coil have different effect when used as the core of a solenoid.
Title: Re: How does induction heater work?
Post by: Bored chemist on 30/05/2023 15:10:38
It shows that a ferrite rod and a steel coil have different effect when used as the core of a solenoid.
That's why ferrite was invented.
Title: Re: How does induction heater work?
Post by: hamdani yusuf on 03/12/2023 08:44:41
Here's a great video explaining how and why induction heaters work.
Title: Re: How does induction heater work?
Post by: Origin on 03/12/2023 18:50:53
Yep, good video and a nice way to end the thread.
Title: Re: How does induction heater work?
Post by: hamdani yusuf on 04/12/2023 02:18:23
Yep, good video and a nice way to end the thread.
He promised a follow up video. If you are no interested, you can simply skip it.
Title: Re: How does induction heater work?
Post by: hamdani yusuf on 14/02/2024 12:34:33

Here's a video of induction heater involving a ferrite rod.
The first interesting thing we can find is that the insertion of ferrite rod can reduce total power consumption, even though it absorbs some energy and generate heat. To do that, it must have taken the energy from somewhere else, e.g. the energy that was previously spread to the surrounding of the coil.
Or the energy that was previously dissipated by the coil.
Title: Re: How does induction heater work?
Post by: hamdani yusuf on 14/02/2024 13:02:38
Quote
0:00​ Wrong Way of Detecting Metal
1:48​ Theory Behind How Metals Effect Inductance
6:10​ More Fake and Real Metal Detector Video Tutorials
7:32​ Designing a ?Simple? Metal Detector Circuit
15:48​ Testing the DIY Metal Detector Circuit
This video provides important information on how metal objects react to induced AC currentcurrent, depending on the frequency.