Resonance in Series and Parallel RLC Circuit

[hermes]

Hi all,

I was researching Parallel RLC when I found this interesting page:

https://electricalacademia.com/basic-electrical/resonance-series-parallel-rlc-circuit/

"When resonance occurs in a parallel RLC circuit, a local current circulates between the inductor and the capacitor. This current can be very high, while the circuit current as seen from the source can be low. This phenomenon is used in induction heaters (in the industry for heating metals when necessary, e.g., heating bearings for mounting or dismounting) and in induction cookers (for domestic use).

In such an application a high current is flowing through an inductor, whereas the current provided by the power line is small. This means that the rating of the wires and breakers are much smaller than the current in the inductor.

The current in the inductor creates (induces) local currents in the piece to be warmed, without even touching it. In the case of an induction cooker, the body of the cooking pan becomes hot owing to local currents created by induction. This is shown in Figure 2.
The efficiency of induction heating is very high, and the process is very fast compared to conventional heating in which a great part of the energy is used for heating air and the intermediate media between the source and the body to be heated."

"In such an application a high current is flowing through an inductor, whereas the current provided by the power line is small"

The problem is the resistance in Parallel RLC. If it is small - the current in the inductor becomes less and I wonder if the current in the induction coil becomes less? if you add something to be heated? My idea is to replace the inductor with a transformer and somehow load it with a high impedance transformer.

I think I have solved the problem with the load on the primary side of an Parallel Capacitor-Transformer. Has anyone of you built a constant current pulse transistor as a primary for free energy generators? I am writing this idea, because I don't want anybody to file and be granted a patent on that idea.

The constant current pulse transistor does exactly as it sounds. No matter how much you load the secondary. The primary current does not change:

https://www.electronics-notes.com/articles/analogue_circuits/transistor/active-constant-current-source.php


Best Wishes, Hermes

P.S I think Don Smith used both parallel and series resonance in his resonance amplifer.

P.S these are the additional links I came across:

https://en.wikipedia.org/wiki/Induction_heating

https://electricalacademia.com/

[partzman]

hermes,

There are many ways to generate a constant current and there are potential applications in FE.  I've attached several papers below to illustrate what I've found in my research.  The problem with any active or passive current source is the compliance voltage or the voltage across the constant current source.

Regards,
Pm

[hermes]

Hi Everyone,

"When resonance occurs in a parallel RLC circuit, a local current circulates between the inductor and the capacitor. This current can be very high, while the circuit current as seen from the source can be low."

Now I have made the first schematic of Hermes RLC-amplifier: It has a squarewave adjustable frequency generator and a constant current transistor. The transistor will be on when 4 is high and off when 4 is low. The 2k2 resistor is a current limiting resistor. The 100k potentiometer adjust the frequency. C Hertz capacitor alternativly charge and disharge. A big capacitor lower the frequency, while a small capacitor increase the frequency.

The transistor can be any small signal transistor with a safe output power of 625 milliwatt. The 22 ohm is a current limiting resistor limiting the transistor collector current to 0.75 Volt/22 ohm = 34 milliampere. The potentiometer that is connected between the 22 ohm resistor and the transistors emitter can be of any value. The higher value the less collector current. The transistor maximum output power is 9 Volts*34 milliampere = 300 milliwatt. The primary output between the collector and +9 volt source can be short circuit without burning the transistor. Also the secondary of the transformer can be short circuit without burning the transistor.

I see that Hermes RLC-amplifier can be used for three things. First find out if there is any larger current circulating between the capacitor and transformer in the RLC circuit. Second a frequency generator for free energy studies and third as a tester for suspected malfunctioning transformer.

Best Wishes, Hermes

http://gratisenergi.se/RLC-amplifier.jpg