In my post last week I started to examine issues around frequency selection for wireless power systems. This week I want to take the discussion a bit further and talk about the benefits (as we perceive) of using lower frequencies (in the kHz range) vs. higher frequencies (MHz) as an industry standard.
As the standards debate rages on, different parties continue to put forward their various interpretations on the ideal frequency range. Various standards utilize higher frequency ranges than others. PowerbyProxi, through the CEA working group, continues to argue that standards that use lower frequency ranges (kHz) are more appropriate based on what we believe is in the best interest for you – the consumer.
There are several factors that need to be taken into account.
Complexity. How complex is the device to manufacture. Controllers used for wireless power systems are far more complex at the MHz range ultimately impacting the cost of manufacture and thus the price that the end-consumer (you) pays.
Interference. As we as we are aware there are no wireless devices operating in the MHz range that meet EMC radiated emission compliance. What it means is that at the moment, there is no proof that they wont cause interference on other devices.
Other factors such as charging distance, transmission efficiency, thermal properties and form factor tend to be implementation specific or require further research to be able to draw clear comparisons.
On the balance of the research done so far, lower frequencies at the kHz allow for more user friendly and functional wireless power systems to be developed. Isn’t that ultimately what it should be all about?