• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1613-1616
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• 2008

A Transcutaneous Energy Transmission System (TET) has been developed for the wireless energy transmission with two magnetically coupled coils. A resonance circuit is used to raise the induced voltage and current of the secondary coil. Its resonance frequency depends on the internal resistance of circuit and the transferred energy. Because the transferred energy usually changes in wide range, the output voltage is unstable and the energy transferring efficiency decrease. A push-pull class E amplifier is usedto generate high frequency AC voltage. To maintain proper resonance frequency, the voltage output of the amplifier was continuously monitored and adjusted to the optimized resonance frequency. Because of its high frequency (370 kHz), a phase lockedloop circuit and a comparator are used to monitor the output waveform. The results of experimentaldata show that the PLL circuit can increase the transmission efficiency and stabilize the output voltage of TET.

• ETRI Journal
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• v.30 no.6
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• pp.844-849
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• 2008

A new transcutaneous energy transmission (TET) system was developed for transmitting electrical power to an implanted device, such as an artificial heart in a patient's body. This new design can maintain a stable output voltage independent of the load resistance. The system includes a compensation capacitor to reduce energy loss and increase power transfer efficiency. Experimental results show that the output voltage of the receiving coil changes very little as the load resistance varies from 14.8 ${\Omega}$ to 15 $k{\Omega}$, which corresponds to a change in output power from 0.1 to 97 W.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.239-240
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• 1998

DTET(Dual Transcutaneous Energy Transmission System) is the stable power transferring unit for TAH(Total Artificial Heart) which uses more power than any other artificial organ. It has better efficiency and safety than an ordinary single TET. By reducing the load, it can reduce the change of supplying current for each single TET and it causes the lower change of efficiency. The increment of magnetic flux in coils enables delivering power through thick skin. It can enable internal batteries remove when will be used in a failure of TET, for a lithium ion battery has heavier weight than TET. A DTET should be studied the effect between each coils that generate magnetic flux. It should be compared the advantage with the weakness when it is used.

• Proceedings of the KOSOMBE Conference
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• v.1992 no.11
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• pp.117-122
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• 1992

In systems in which inductive coupling between a pancake-shaped coil on the surface of the body and a similar coil within the body is utilized for the transfort of electromagnetic energy, the minimization of temperature rise in the tissue is intimately related to the achievement of minimum losses in the region of the implanted coil. The new class of amplifiers, named "class E", for inverter is defined and is illustrated by a detailed description and a set of desist equations for one simple member of the class. For TET circuit the authors measured 65 to 76 percent efficiency at 1985kHz at 30 to 50 W output from IRF250 MOSFET transistor.