Sort of. From my understanding nobody has a working model of his technology (or similar technologies), but we do understand at least the basics of how they work. Some names to start your research are Eric Dollard, John Keely, Dewey Larson, John Bedini, Walter Russell, Tom Bearden, Ken Wheeler, and there's more, that's off the top of my head.

Each of them have slightly different theories as to how the universe works, but there's great similarities between how all of them think. The core principles seem to be...

-The Universe seems to be an interplay of two opposing forces, Gravitation and Radiation (One inward/concentrative force and another outward/expanding force)

-Aether Theory > Atomic Theory (All space is filled with an Aether, and matter is just the motion or "flow" of that Aether. Take empty space which is the base state of the Aether and induce motion in the form of a toroidal vortex waveform and concentrate it, and you get matter. Light, Sound, gravitational waves, etc are just certain motions/flow states or "waves" in the Aether)

-Electricity is 4-dimensional rather than 2-dimensional (Flows through space and counter-space, also involves dielectricity and magnetism. Modern electrical theory doesn't recognize all of the dimensions, only some of them. Using all of the dimensions of electricity should allow for all this "space age technology" we hear about, faster than light travel, electricity transmission over distance instantly without losses, zero point energy, etc)

-Figuring out how Electricity works would also allow for healing technology, and other "dangerous" technologies. As matter is simply a "flow structure" of the Aether, and electricity is also a movement or waveform of the Aether, applying Electricity in the proper way should be able to form, change, or dissolve matter at will. Could be used for the good, or for evil. This may be part of why this technology was hidden in the first place. That kind of power in the wrong hands could be planet/civilization destroying, and would make nukes look like firecrackers

-Resonance/Harmonics plays a big part into it I think. Think of how pushing a kid on a swing requires a very small amount of energy to cause a lot of movement if you push the kid at exactly the right time, in comparison to random pushes with random amounts of force. Applying power in a specific resonant way could allow the extraction of energy that's hundreds (thousands) of times the amount of energy that's put in. Tesla mentions 3s, 6s, and 9s to be extra important for some reason. Maybe experiment with feeding a coil the 3rd, 6th, and 9th harmonic of the calculated resonant frequency of the coil? Tesla did a lot of work with impulses, so make sure these are impulses being fed in?

Idk, being completely honest I don't really know entirely what I'm talking about, I've just tried reading as much as I possibly can from Tesla, and anyone who's trying to do anything remotely related to what he was doing. I feel like if we crowdsourced research and had a whole bunch of people a lot smarter than me work together, we might get somewhere on this. Maybe we should create an "electricity.win" or something, and have as many people as possible start reading these papers and books, start bouncing ideas off of each other. I bet within a year we could crack the secret. Plus doing this sort of research takes a lot of equipment. Some of us know a lot of the theory of tesla tech but don't have equipment to test it, others have rooms full of equipment but have no idea where to begin.

This got kinda long and messy, but anyone with me? I'm being serious here that I think this can be done.