[moved] wireless power transfer for battery charging

Hi friends

Well iam working on a project wireless power transfer for battery charging of electric vehicle, i would like to simulate the resonante inductive coils (series or parallel resonance condition) with MATLAB simulink software i tried with mutual inductance block i am getting very less efficiency but in various literature they got up to 90% efficiency(in MATLAB simulink). please help me how to develop inductive coupling in MATLAB simulink. Please help me in developing of 1KW resonant inductive power transfer for battery charging in MATLAB SIMULINK with an output voltage of 24 volts. Please help how to develop it MATLAB Itried with mutual inductance block but iam not getting properly so please kindly help me in this it will be a great help thank you in advance.

Re: wireless power transfer for battery charging

Maybe you could show the circuit to see why does that happen ?

I assume you have already reviewed what Mathworks says about implementing Mutual Inductances

Re: wireless power transfer for battery charging




i have gone through the implementing mutual inductance even also iam not getting proper efficiency.
here iam sendinf the circuit sir.
thank you sir

Re: wireless power transfer for battery charging

Looks like a useless post unless you manage to tell actual design parameters.

Re: wireless power transfer for battery charging

Sir the circuit describes that wireless inductive resonance power transfer system, the inverter switching frequency is equal to the resonance frequency , the values of elements are
L1=L2= 362 micro henry
C1=C2= 0.43 nano farads
VDC=65 VOLTS

Re: wireless power transfer for battery charging

I thought about complete parameters...

e.g. M, f, RL, IGBT and diode specification.

Re: wireless power transfer for battery charging

Two comments:- Use a centre tapped L2 and a pair of diodes , save a diode volt drop. There is no loss resistance shown in series with L1, as shown it has infinite Q.
Frank

Re: wireless power transfer for battery charging

kishan89 said:

i have gone through the implementing mutual inductance even also iam not getting proper efficiency.

Click to expand...

Your circuit simulation, as mentioned by others, do not implement real life parameters. So, even if you achieve great efficiency, in real life will not be so. Try a more realistic model, like, adding the ESR of inductor (even though at the operating frequency will be higher), on resistance of IGBTs. Also your M which is equal to k·L, for a realistic model should be low as "k" is low.

Re: wireless power transfer for battery charging

Can it be called "wireless" when the two coils are touching?

Re: wireless power transfer for battery charging

Can it be called "wireless" when the two coils are touching?

Click to expand...

They are not necessarily touching, mutual inductance M can have very low values to model distant coils. But usual wireless charging methods, e.g. the Qi standard implemented by recent smart phones, also experimental electric car chargers have a coils distance much smaller than diameter and achieve moderate coupling factors.

Here is a graphic representation of the coupling coefficient as a function of the distance between the coils i.e. k=f(d)



The equation that make me able to plot that comes from this IEEE paper: "Active Resonance Wireless Power Transfer System Using Phase Shift Control Strategy"

At a zero distance between coils, the system is detuned because k=1, so, resonant coupling is used just in case the coupling coefficient is small.

Practical limitations from any wireless powering system will come from the series resistance (Q factor) of your resonators (in this case, the inductors will be dominant) and the coupling coefficient (k) between the two. This maximum theoretical limit is described well in this open white paper: https://www.witricity.com/assets/highly-resonant-power-transfer-kesler-witricity-2013.pdf

After that, all of the deviations from achieving this theoretical maximum can be attributed to impedance matching. Often IM networks are placed between the source and the Tx resonator, and the Rx resonator and the load. I'm not entirely sure if such networks are still required for low frequency, high k applications.

Is there any particular reason you are using Matlab simulink? I'm not very familiar with the tool, but from what I understand doesn't it seem a bit over complicated when PSPICE or some other circuit simulator could simulate your circuit relatively easily?