Pradhan Full wave analysis of single and coupled shielded image guide for millimeter wave applications Rajiv K.
Split ring resonator thesis the induction coil shown here the circuit draws about 5A from a 15V supply when a screwdriver tip is heated. It takes approximately 30 second for the tip of the screwdriver to become red hot!
The control circuit uses a method known as ZVS zero voltage switching to activate the transistors which allows for an efficient transfer of power. In the circuit you see here, the transistors barely get warm due to the ZVS method.
Another great thing about this device is that it is a self resonant system and will automatically run at the resonant frequency of the attached coil and capacitor.
If you want to save some time, we have an induction heater circuit available in our shop. You might still want to read this article though for some good tips on getting your system working well.
How Does Induction Heating Work? When a magnetic field changes near a metal or other conductive object, a flow of current known as an eddy current will be induced in the material and will generate heat. The heat generated is proportional to the current squared multiplied by the resistance of the material.
The effects of induction are used in transformers for converting voltages in all sorts of appliances. Most transformers have a metallic core and will therefore have eddy currents induced into them when in use. Transformer designers use different techniques to prevent this as the heating is just wasted energy.
In this project we will directly make use of this heating effect and try to maximise the heating effect produced by the eddy currents. If we apply a continuously changing current to a coil of wire, we will have a continuously changing magnetic field within it.
At higher frequencies the induction effect is quite strong and will tend to concentrate on the surface of the material being heated due to the skin effect.
Typical induction heaters use frequencies from 10kHz to 1MHz.
Very high temperatures can be generated with this device! The Circuit The circuit used is a type of collector resonance Royer oscillator which has the advantages of simplicity and self resonant operation.
A very similar circuit is used in common inverter circuits used for powering fluorescent lighting such as LCD backlights. They drive a center tapped transformer which steps up the voltage to around V for powering the lights.
In this DIY induction heater circuit the transformer consists of the work coil and the object to be heated. The main disadvantage of this circuit is that a center tapped coil is needed which can be a little more tricky to wind than a common solenoid.
The center tapped coil is needed so that we can create an AC field from a single DC supply and just two N-type transistors.
The center of the coil is connected to the positive supply and then each end of the coil is alternately connected to ground by the transistors so that the current will flow back and forth in both directions.
The amount of current drawn from the supply will vary with the temperature and size of the object being heated. From this schematic of the induction heater you can see how simple it really is.
Just a few basic components are all that is needed for creating a working induction heater device. R1 and R2 are standard ohm, 0. The value of these resistors will determine how quickly the MOSFETs can turn on, and should be a reasonably low value.
They should not be too small though, as the resistor will be pulled to ground via the diode when the opposite transistor switches on. They should be diodes with a low forward voltage drop so that the gate will be well discharged and the MOSFET fully off when the other is on.
Schottky diodes such as the 1N are recommended as they have low voltage drop and high speed. The voltage rating of the diodes must be sufficient to withstand the the voltage rise in the resonant circuit.
In this project the voltage rose to as much as 70V. They were mounted on heatsinks for this project, but they barely got warm when running at the power levels shown here.The main work in this thesis is to explore novel microwave filters with more compact size and improved performance by taking advantage of new substrate integrated waveguide (SIW) structures, such as the ridge substrate integrated waveguide, half mode substrate integrated waveguide (HMSIW) and SIW with complementary split ring resonators (CSRRs).
AFIT-ENG-MSM TUNABLE TERAHERTZ METAMATERIALS WITH GERMANIUM TELLURIDE COMPONENTS THESIS Presented to the Faculty Department of Electrical and Computer Engineering. ENGLISH ABSTRACT: This thesis describes the selection, design, adaptation and construction of a folded split ring resonator (FSRR) antenna to replace the existing transmitting antenna in an animal-borne behavioural monitoring system (ABBMS).
Figure 5: Split ring resonator (SRR) metamaterial: (a) the changing magnetic flux in a uncut single ring structure induces a current that generates field opposing the change in applied magnetic flux (b) SRR is a double-ring structure with cuts that form capacitors.
Title of the Thesis; Alok Kr. Gupta. Characterization of Two new Types of Fin Line Discontinuities. Akhilesh Jain.
Dual Band Filter using Split Ring Resonator: Ashok Kumar Jyani. Dielectric Resonator Antenna with Filter: Yogendra Arya. Design of filter synthesis with non uniform Q-factor.
Debdeep Sarkar, Kushmanda Saurav and Kumar Vaibhav Srivastava, "Four-element Array of Complementary Split-Ring Resonator loaded Printed Directive Dipoles for Triple band Applications," Electronics Letters, vol.
His research studies the properties of a printed microwave resonator microplasma source for in-space micro propulsion. He received his M.S. degree from UAH in and is currently a Ph.D. candidate working on his dissertation entitled: "Study and development of a split-ring resonator for micropropulsion.". Dual-band bandpass filter using embedded split ring resonator Dual-band superconducting bandpass filter using stub-loaded resonators with controllable coupling dual-mode dual-band ring resonator bandpass filter with microwave. Wright-Patterson Air Force Base, Ohio APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED The views expressed in this thesis are those of the author and do not reflect the official.
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