HFSS low frequency (100 KHz) coil simulation

Hello,
i'm using HFSS to simulate a transmitter coil for Wireless power transfer (100 KHz).
My question is about the radiation box dimensions, it seems that when i increase its height the results shift quickly form the desired ones.
However, i'm not sure how to choose because to get the correct values i have to make the box very close to the antenna.

Thanks in advance for your help.

Sounds like a conceptual problem of your project. A 100 kHz coil doesn't radiate relevant energy amounts to the far field, instead its magnetic field couples to a nearby receiver coil (if any). You can use a radiation box as boundary of your simulation volume, but you need a receiver coil for energy transfer simulation.

Correct. As FvM mentions there is no far field radiation, and the coupling in wireless charging is inductive. Simulating a single coil is useful to calculate/optimize the Q factor. Coil Q factor is relevant because it determines the charging efficiency.

If you want to use HFSS, use absorbing boundaries (PML) and you should see little effect from the boundaries if you place them at least 1 inductor diameter away.

I have implemented wireless charging coil optimization (PCB for WPC/Qi) with a planar EM solver (ADS Momentum) which is more efficient for this type of problems.
http://muehlhaus.com/products/pcb-inductor-toolkit

Thank you for your answers.
Well as a first step, i wish to visualize the radiated magnetic field and find the inductance of the coil.. then i will move on to adding the receiver and studying the transfer of energy..

Regards

Hello Volker,
The link you have given is not working.
Are you sure the tool kit you are providing on the website are for WPC coils? 125Khz?
Website shows expertise on High frequency inductors ( RFIC)?
Does this firm take complete responsibility of delivering WPC coil to client?