Every year The University of Auckland Power Electronics department holds an IPT car race which is a part of their final year design project. In 2014 PowerbyProxi had the privilege of sponsoring the event (called the PowerbyProxi challenge), which involves students designing an inductive power system to deliver power to a radio controlled car that is raced on a circular track.
The event which was held on June 6th, required students to design a pick-up coil, pick-up controller, and an output power regulator which will efficiently deliver power from a transmitting racetrack to an RC car. The challenge of the course is to pick-up maximum power from the track and also convert it in such a way as to provide optimum acceleration to the DC motor which drives the car.
After a semester of learning and many hours spent in the labs, the students were finally given the chance to test their designs in the first round of qualifying: a drag race. Every pair of students was allowed to place their circuit into an RC car, and compete for time along a single track of approximately 10 meters. The drag race is a pure test of speed, and measures the performance of the design. The 8 teams with the fastest qualifying times are invited to compete in the finals, with a $300 prize at stake.
In contrast to the drag race, the finals are set on an ovular track which tests not only circuit performance but also driver handling. The track was set up in the foyer of the ECE department and many students and faculty gathered to watch the annual competition. The sponsor PowerbyProxi had a healthy representation at the event, as 12 engineers (mostly UoA alumni) from the company travelled to the university to support the students.
Students competed 1v1 in the best of 3 races. Round after round, students were eliminated as those with superior driving and circuit performance made their way to the later round. A dramatic final eventually provided a winner, who was congratulated with rapturous applause from the more the 50 strong crowd. PowerbyProxi engineering manager, Kunal Bhargava, presented a trophy and the prize money to the deserving students.
But the drama wasn’t over! As a final test of their design, the students were given the opportunity to race against the faculty designed vehicle. The staff car was driven by Arunim Kumar from PowerbyProxi. The University of Auckland alumni gave the rookie engineers a clinic as he won 3 straight races against the newly crowned champions.
At the end of the day, the PowerbyProxi challenge provided the Power Electronics students with a fun way to test the designs and round out the semester. PowerbyProxi is grateful for the opportunity to support the up and coming IPT engineers in this challenging and exciting course, and the company looks forward to its continued involvement in future years.
You know, the funny thing is, wireless power is the oldest new technology ever. The University of Auckland has been a Wireless Power Centre of Excellence since the 1980s when it started developing real customer solutions. My Professor John Boys filed our first patents in 1991. We regard John as the Godfather of wireless power.
Our CTO, Dr Patrick Hu moved to Auckland from Xian specifically to study wireless power at Auckland. He too has trained many of our PhD’s.
PowerbyProxi was spun-out from The University of Auckland. Today, at the time of writing we have over 125+ patents with over 900+ claim (real patents, protecting real products I should add).
Many of you will be familiar with HaloIPT – which Qualcomm recently acquired. Like us, HaloIPT was also a University of Auckland spin-out. Now just to clear up some confusion, HaloIPT or now Qualcomm has an exclusive license to the University of Auckland’s wireless power portfolio, for use in the field of recharging electric vehicles.
In addition to our own portfolio, PowerbyProxi has an exclusive license to the same Univ. of Auckland portfolio but for all consumer electronics devices, semiconductors and batteries (in addition to several other industrial application fields).
Who remembers early pioneers Splashpower? So as a company, we took a different path and chose to focus on unplugging the power cable in wet, dirty and moving industrial applications whilst maturing our technology to the point we believed consumers would embrace.
We have leveraged this experience building solutions for the most difficult and demanding industrial applications in the consumer space.
We’ve miniaturized our loosely coupled wireless power
Over the last few years Wireless Power has made rapid advances towards becoming a mainstream technology and is often the case, marketing departments become the source of many new inventions. Perhaps the biggest marketing “invention” to date is something called “Magnetic Resonance” (related to Resonant Inductive Coupling) when everyone else is just doing stone age “Inductive Power.”
It’s a term many have now adopted, as if it was some space-age technological leap from “Inductive Power.” When in fact Magnetic Resonance and Inductive Power are EXACTLY the same thing.
Lets dig into this a little more …
I’m sure all EEE majors will remember that Inductive Power uses Magnetic Resonance.
Any Inductive Power system has to have resonance, even the WPC which requires complete alignment between the transmitter and receiver coils uses resonance. Yes, tightly coupled systems, like loosely coupled systems, do use resonance! This is accepted science since The University of Auckland started researching modern day wireless power 20 years ago.
Originally, before induction, wireless power could be achieved by effectively taking a transformer and separating the primary and secondary coils (i.e. a split transformer).
To increase the power efficiency it was worked out a long time ago that we need to use resonant coupling. This is just a fancy way of saying that by adding capacitors on both coils, a resonant circuit is created between the inductance of coil and capacitor. At the resonance frequency, the reactance cancels out and you are left with only the parasitic effects of finite winding resistance, AC resistance (proximity effect) and dielectric losses.
If you had a perfect AC source and drive the resonant circuit you have no losses. Losses are solely limited by your parasitics.
“Magnetic Resonance” is just sticking some capacitors in place. It was great to see Marin Soljacic, the inventor of WiTricity confirm this in the IEEE publication, A Critical Look at Wireless Power. “Resonance enables efficient energy transfer…. …. it’s not a new idea: Tesla’s eponymous coils use that very same principle.”
To summarize in non-technical speak, all Inductive Power systems use magnetic resonance and its certainly not the difference between tightly coupled and loosely coupled systems.
Like most new technologies you need to get underneath the marketing spin to understand the features and benefits that each vendor can deliver to those who matter most – our customers!