Suggestion for a Solid State Tesla Coil Based Upon International Rectifier IR2153D Self-Oscillating Half Bridge Driver Chip

From the Tesla Coil List, Original poster: "David Sharpe by way of Terry Fritz

All

While searching the outer reaches of the Internet "Empire" for information on series resonant half-bridge converters for
possible service for SSTC, I think I found a hidden diamond in the rock pile.  The driver control chip is an International
Rectifier IR2153D, and it is predominantly used for SS fluorescent lamp ballasts.  The advantages to the experimenter
are:

1. Readily available at Digikey for less then $3.00 ea. (US)
2. Is functionally a combination of a 555 oscillator + T flip-flop and high and low side half bridge HV FET driver (600V level shift no less)!!!   :^)  Useful frequency from 10's of kHz to ~300kHz (or more).
3. Chip will operate from ~10V to 600V input (with proper Vcc 5mA current limiting resistor or 5mA constant current source)
4. Integral soft start and shut down (external gating) by pulling Ct pin low.  This will facilitate modulation efforts or hard shutdown with an overcurrent or fault condition.  Also may facilitate a highly desirable VCO function with only a few additional passive components.
5. Frequency adjustable by adjusting Rt value, in fluorescent lamp reference below (see first reference application circuit).
6. Minimal parts count to build a SSTC from 50W to 1kW or more.
7. May have sufficient drive to operate IGBT's in ZVS/ZCS operation.

Reference the following links:

Students build their own Switched Mode Power Supplies or how to promote Power Electronics at Universities
This is a discussion showing pertinent use of IR2153 (pgs 7-9) for a half-bridge series resonant converter.  Note the waveforms of the converter sinusoidal current versus square wave voltage input (yep, it is ZCS - zero current switching).  This is the key that suggested the use of this chip for SSTC applications.

[Abstract. The paper presents a concept of labwork in “switched mode power supplies” for students at universities as a supplement to the lecture.  Aim of the labwork is to make power electronics more attractive to students, especially to those who originally preferred non power related subjects.  Three power circuits have been prepared to be built by the students. These are a step down chopper, a flyback converter and an electronic “DC-DC transformer” based on a series resonant converter.  Within the course the students learn to design and build reactive components, they use a smart power IC, insert a voltage control loop and they get an impression of resonant topologies.  Thus, the laboratory work covers many different subjects of electrical engineering. The theory is presented in the lecture while most information of the labwork (e.g. datasheets) are available via internet.  Up to now the labwork has been carried out 2 times at the FH Köln and the RWTH Aachen.  It found high interest among all participating students who enjoyed building their own SMPS circuits.  The success of the labwork can also be seen in the fact that many of the students have been encouraged to chose power electronics as a subject for their diplom thesis.]

IR2153(D) (S) Self-Oscillating Half Bridge Driver datasheet from International Rectifier.

Fluorescent Ballast Design Using Passive PFC and Crest Factor Control by Peter N. Wood
Describes using IR215x chips in ballast circuits, and using external passive components create a VCO function based on lamp current.  (Gee, if based on resonator base current -- a self tuning SSTC??   :^)   )  Also notice that if the primary of the SSTC replaces the 1mH ballast inductor, the "guts" of a SSTC are all there.

I'm buying some at work for another project and give it a whirl...

Regards
Dave Sharpe, TCBOR
Chesterfield, VA. USA