Musical ZVS circuit operation - Page 1
Forum section: electronics / projects

author: SKHILLBILLYSlures
author_rank: Regular Contributor
timestamp: June 30, 2017, 06:46:35 pm
content: Could anyone figure out how to make a ZVS circuit operate under load at 300khz or so I'm trying to construct a musical ZVS circuit that doesn't have any harmonics below 25khz so that the audio signal is not affected by the driving waveform I'm looking for it to operate at about 10amps 12-36V DC any suggestions because I've played with a software program you cheaply purchase for Android and it doesn't operate unless it injects noise and furthermore the program only implements Ideal components not actual ones for example it will say n channel mosfet instead irf540 or irf260

author: jbb
author_rank: Super Contributor
timestamp: July 01, 2017, 12:18:31 am
content: ZVS circuits commonly operate at those frequencies, so it should be possible.For circuit simulation I thoroughly recommend LTSpice (it's free, available fromwww.linear.comand works for Windows, Mac and Linux (with WINE)).Please note that simulators only produce results based on what you give them. For example, LTSpice will happily simulate a little transistor dissipating 1kW, even though a real circuit would have gone bang by then.

author: SKHILLBILLYSlures
author_rank: Regular Contributor
timestamp: July 01, 2017, 04:43:35 pm
content: Awesome but any suggestions for one that has variable frequency under load

author: Molenaar
author_rank: Regular Contributor
timestamp: July 01, 2017, 08:59:32 pm
content: Isn't a resonant ZVS not intrisically mostly sinusoidal, i.e. no harmonics to speak of?

author: SKHILLBILLYSlures
author_rank: Regular Contributor
timestamp: July 02, 2017, 12:28:30 am
content: The model I played with constructed a square wave due to the mosfet switching that also appears to be driving the oscillation between the capacitances and inductances ?

author: jbb
author_rank: Super Contributor
timestamp: July 02, 2017, 03:40:32 am
content: Quote from: SKHILLBILLYSlures on July 01, 2017, 04:43:35 pmThe term 'ZVS' describe a wide range of topologies. Some are constant frequency, some are variable frequency.But you were asking about f_s > 300kHz. That's way above the audio band, so why worry if f_s changes a bit?

author: SKHILLBILLYSlures
author_rank: Regular Contributor
timestamp: July 02, 2017, 03:51:43 am
content: Many audio teslas I build resonate at various frequencies above 300 Khz and the ZVS driverusually behaves as if there wasn't a load in the out put windings at least ones that haven't been heavily tweaked by adding a fly back transformer which I hate using because they fry like chicken and not all of the teslas I build are the same inductance and wish I had a circuit topology that could handle a very wide range of different size teslas and they Especially fry like chicken because I have an audio power amplifier coupled with the inductor that is used in the circuit to introduce my audio signal in order to get it to audio output over an arczap speakerI understand that this probably isn't the best way to implement audio probably creates a crapload of noise but it's the easiest and as for it's operation will have the drive frequency which would be 💯 silent then I can drive the audio through the inductorAlso using the flyback transformer coupled design is GINORMOUSly inefficient and when I seriously plan on putting of these in my vehicle inefficiency is not an option it will likely drain the battery very quickly if the truck is turned off and with the plan to utilize a class A output stage on my amp if I could get it down to just quickly instead of very quickly draining the battery this would be the ultimate goal