EV Coil Parameter EstimatorV1.0
developed by Sutanu Chatterjee · project supervisor: Prof. Polina Kapitanova · Department of Physics · ITMO University
This estimator utilises fitted curves of previously performed FEM simulation results and solves quadratic and cubic polynomial functions in real time to estimate coil parameter values instantly, based on two major variables of importance to WPT systems: air gap between the coils and number of turns of the individual coils.
SAE J2953_202010 FEM-fitted polynomials Aluminium shield model
Sliders recalculate live · Enter also recalculates
System parameters
160
10510
10
725
0
05
Parameter definitions
  • dAir gap — physical distance in air between the two coils (mm). The coupling coefficient k depends directly on this variable.
  • NNumber of turns — winding count of each coil. Inductance, resistance, mutual inductance and Q factor depend on it.
  • tAluminium shield — thickness of each screen (mm).
Terms of use
TERMS OF USE
This application provides estimated results, which may vary depending on several parameters that are not in control of the developers. We do not guarantee 100% accuracy and this application only provides estimated results based on the simulations that we performed.
Result
Estimated efficiency
Press “Estimate”
RF–RF / AC–AC (%)
Coupling k
—
Mutual inductance M
—
TX coil L₁
—
RX coil L₂
—
Mean inductance
—
Q factor
—
DC resistance
—
Working frequency
85 kHz
Coupling geometry
TX / RX coil conductors air gap d · turn pitch ferrite aluminium screen t turns drawn for clarity
Notes

Conforms to the SAE J2953_202010 standard. Values are produced from fitted FEM curves evaluated as cubic and quadratic polynomials in real time.

This estimator was developed by Sutanu Chatterjee under the supervision of Prof. Polina Kapitanova. The fitted curves and equations come from the published paper below.

Based on the authors’ published paper: Chatterjee S, Zolotarev A, Terenteva P, Baranov G, Kapitanova P. 2025. Real-time estimator of parameters for coupled coils in an 11-kW wireless charging system for electric vehicles. Wireless Power Transfer 12: e027. doi: 10.48130/wpt-0025-0019

The standalone version offers more functionality including curve scanning. We are able to make a custom one based on your parameters. Please contact us.