4 ms·

A few pieces of context - this builds on the insight that underlies WiTricity - https://witricity.com https://witricity.com - near-field coupling of designed re

A few pieces of context - this builds on the insight that underlies WiTricity - https://witricity.com https://witricity.com - near-field coupling of designed resonators for non-radiative power transfer. Specifically, this can enable very high efficiency wireless transfer in the near-field of resonators, which at these wavelengths is on the order of 1-5 meters. This is qualitatively different from other approaches to wireless power transfer and does have some real scientific insight which originates from the electromagnetics/ photonic community. More specifically, this specific results builds on an insight from the same research group which led to a Nature paper in 2017: https://www.nature.com/articles/nature22404/ https://www.nature.com/articles/nature22404/ - that using an non-linear saturable gain element in a parity-time symmetric configuration enables robust power transfer in a range of conditions such as moving and the presences of obstacles. There's interesting underlying science here that shouldn't be missed for the focus on the application.

madengr 6y ago
Interesting. Several years ago I designed a resonate, near field wireless charging platform and used a simple X5R capacitor; the nonlinearity of the X5R dielectric to provide regulation. As the distance increased, the resonant frequency and Q increased, increasing the potential across the X5R, which decreases the capacitance, changing the resonant frequency. Though I can’t remember if I placed the X5R in series or shunt. Though it mainly helped with regulation depending on current draw of the receiver, it did provide some range increase.
andygreenwell 6y ago
Interesting development in this space this week for WiTricity (the company) is that China is standardizing nationally on magnetic resonance technology for wireless vehicle charging based on WiTricity’s designs and standards work. I’m sure this was an exciting week for my former colleagues there, and congratulations are certainly in order for them. https://www.greencarcongress.com/2020/05/20200508-witricity.html https://www.greencarcongress.com/2020/05/20200508-witricity.... There are academic connections between the group at Stanford publishing this work and the group at MIT that founded WiTricity.

madengr 6y ago

Interesting. Several years ago I designed a resonate, near field wireless charging platform and used a simple X5R capacitor; the nonlinearity of the X5R dielectric to provide regulation. As the distance increased, the resonant frequency and Q increased, increasing the potential across the X5R, which decreases the capacitance, changing the resonant frequency. Though I can’t remember if I placed the X5R in series or shunt. Though it mainly helped with regulation depending on current draw of the receiver, it did provide some range increase.

andygreenwell 6y ago

Interesting development in this space this week for WiTricity (the company) is that China is standardizing nationally on magnetic resonance technology for wireless vehicle charging based on WiTricity’s designs and standards work. I’m sure this was an exciting week for my former colleagues there, and congratulations are certainly in order for them. https://www.greencarcongress.com/2020/05/20200508-witricity.html https://www.greencarcongress.com/2020/05/20200508-witricity.... There are academic connections between the group at Stanford publishing this work and the group at MIT that founded WiTricity.