In order to compensate displacements of transmitting and receiving inductance coils, a method of changing capacitor capacitance in the transmitting part of system of inductive power transfer to implantable devices is applied. However, the use of this method doesn’t give a complete solution for the problem of controlled capacitor capacitance management. In this work, to maintain a constant output power in an inductive power transfer system, a method for compensation of inductance coils displacements is proposed using pulse-width modulation (PWM) actuation of circuit capacitance by means of two series capacitors and a switching transistor connected in parallel to one of the capacitors. The effect of PWM signal duty cycle, PWM signal frequency, as well as the intrinsic characteristics of the transistors on the amount of output power in the inductive power transfer system based on PWM actuation of capacitance was studied. It was demonstrated that there are many combinations of capacitances of two capacitors that can achieve the required equivalent capacitance even with identical PWM signal duty cycle. It has been established that increasing the PWM signal frequency and reducing the switching transistor transconductance allow the rise in the output power of inductive power transfer system.
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Key words:
wireless power transfer, inductive coupling, implantable medical devices, capacitors, parasitic components
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Published in:
BIOMEDICAL ELECTRONICS
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Bibliography link:
The work has been supported by the Ministry of Education and Science of the Russian Federation (Agreement no. 075-15-2024-555).
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Financial source:
Gurov K. O., Mindubaev E. A., Danilov A. A. Application of PWM actuation of capacitor capacitance to stabilize the output characteristics of the implant inductive power supply system. Proc. Univ. Electronics, 2025, vol. 30, no. 1, pp. 87–93. https://doi.org/10.24151/1561-5405-2025-30-1-87-93
Konstantin O. Gurov
National Research University of Electronic Technology (Russia, 124498, Moscow, Zelenograd, Shokin sq., 1)
Eduard A. Mindubaev
National Research University of Electronic Technology (Russia, 124498, Moscow, Zelenograd, Shokin sq., 1)
Arseny A. Danilov
National Research University of Electronic Technology (Russia, 124498, Moscow, Zelenograd, Shokin sq., 1)
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