3 ms·

The most important thing here is the 92% efficiency and how "ideal" things had to be in order to achieve that. Wireless power transfer typically has an efficie

The most important thing here is the 92% efficiency and how "ideal" things had to be in order to achieve that. Wireless power transfer typically has an efficiency curve that looks like the Washington Monument - or a middle finger, on a chart. Off by a hair and your efficiency is in free fall down the sides. Alignment, distance, frequency, impedance, parasitics...pick a dimension and it's all FU charts. So I am wondering if they made a system that can actively dial all these in given a real world scenario, or if they hand placed everything to ensure perfect alignment on all fronts, then took an efficiency measurement. Edited to add: A neat fact though is that when you dial in all those parameters as near to the ideal as you can, you actually can get over 99% efficiency. These are what transformers are. The electrical things, not the AI models.

malfist 2y ago
This can be managed like an induction stove. Many small coils instead of one big one. Small coils outside the optimal position just turn off. Much like an induction stove can detect the pot size
- Workaccount2 2y ago
  Induction stove coils just need to induce currents above them in what is essentially a giant shorted out single turn secondary. Which is basically useless, hence why it just makes heat. Granted, it is useful for cooking! Wireless power transfer on the other hand needs carefully aligned coils in order to avoid doing exactly what an induction cooker does - turn usable electricity into heat.
  - malfist 2y ago
    There is no electrical difference between an iron pot that heats up from an inductive load, and circuit that takes that inductive load and directs it to chemical energy storage. The iron pot just doesn't conduct it anywhere useful
    - Workaccount2 2y ago
      Right, and if you bend and mold the iron pot into the shape necessary to conduct it somewhere useful (like chemical energy storage) rather than just turn to heat, you will find than an array of micro coils will hardly work at all. There are grid-array tiny coil wireless energy devices, but the grid is used to find a "best fit" coil depending on the alignment of the device to be charged, and then uses just that coil. Again, a cast iron pot acts as a single huge shorted secondary turn. And a shit one at that (hence why it gets so hot), otherwise the primary (the cook top) would burn up too. You want the opposite of this for electrical energy transfer (low loss, low heat)! I'd probably lose my job if I didn't know this

malfist 2y ago

This can be managed like an induction stove. Many small coils instead of one big one. Small coils outside the optimal position just turn off. Much like an induction stove can detect the pot size

Workaccount2 2y ago
Induction stove coils just need to induce currents above them in what is essentially a giant shorted out single turn secondary. Which is basically useless, hence why it just makes heat. Granted, it is useful for cooking! Wireless power transfer on the other hand needs carefully aligned coils in order to avoid doing exactly what an induction cooker does - turn usable electricity into heat.
- malfist 2y ago
  There is no electrical difference between an iron pot that heats up from an inductive load, and circuit that takes that inductive load and directs it to chemical energy storage. The iron pot just doesn't conduct it anywhere useful
  - Workaccount2 2y ago
    Right, and if you bend and mold the iron pot into the shape necessary to conduct it somewhere useful (like chemical energy storage) rather than just turn to heat, you will find than an array of micro coils will hardly work at all. There are grid-array tiny coil wireless energy devices, but the grid is used to find a "best fit" coil depending on the alignment of the device to be charged, and then uses just that coil. Again, a cast iron pot acts as a single huge shorted secondary turn. And a shit one at that (hence why it gets so hot), otherwise the primary (the cook top) would burn up too. You want the opposite of this for electrical energy transfer (low loss, low heat)! I'd probably lose my job if I didn't know this