Investigation of coil geometry for transcutaneous energy transmission for artificial heart

Abstract

A b s t r a c t -Transcutaneous energy transmission for a totally implantable artificial heart system has been considered and the non-contact electric energy transmission by means of the spiral coils with the amorphous magnetic fiber was reported. The coil design for higher transmitting efficiency and less temperature rise of the coil has been investigated. The experiment i II vi t r o showed that temperature rise w i l l be reduced within 3' C. I . INTRODUCTIONElectrical energy can be transmitted by means of the inductive coupling between two coils separated facing each other.Many papers reported such atranscutaneous energy transmission system [11-[5]. The pair of coils we proposed[6] has features of thin shape and flexibility. Fig. 1 illustrates the structure of the coils. Amorphous wires a r e attached on the back of the spiral conductive coils. The distance between two coils is denoted as g. The conducting wire, for example, composed of 100 pieces of electrically insulated copper wires of 100 um in diameter and was formed into a spiral. 12,000 pieces of amorphous wires of 120 um In diameter were attached radially on the spiral coils. The diameter and the number of turns of each coil are 50 mm and 16, respectively. The thickness is about 2 mm. A pair of the coils could transmitted electrical power over 50 Watts transcutaneously. [6]The vibrating pump[71 developed for artificial heart was driven by the transmitted electrical energy through the pair of coils described above and the flow quantity of 8 L/min was observed. Outlet pressure was 100 mmHg.In order t o reduce the temperature rise of the coils we discuss the transmitting efficiency and coil geometry utilizing an equivalent circuit analysis.

Analysis, design and control of a transcutaneous power regulator for artificial heart

“…Using the power level and size of cores used in [9], [13], [17], [20], [21], we have built our own a transcutanous transformer using Planar Core E64/10/50 for an air gap length (skin depth) ranging from 10 mm to 20 mm. the example transformer emulated represent the trend of leakage inductances and mutual inductance of other transformer designs [3], [7], [9], [11], [12], [15]- [22]. Therefore, as our target is on the design and control of a power regulator for transcutaneous converter application, the parameters of the example transformer should be adequate.…”

“…Discussion on the importance of battery power source can be found in [14]. For higher power applications, such as powering the artificial heart for a power level of 10-60 W, magnetic cores are used [3], [7], [9], [11], [12], [15]- [22]. To compensate for the large leakage inductances due to transcutaneous separation, resonant type converter of class D [9], [13], [17], [20], [21] is used.…”

A new control method depending on primary phase angle of transcutaneous energy transmission system for artificial heart

“…Because, in the point of view of reliability and robustness, a feedback control depending on signal transmission system from the internal unit to outer unit should be avoided. Our first approaches were to optimize the coil geometry [8] and the setting of electrical and magnetic parameters [9]. In this paper, we propose and examine a new control method for stabilizing output voltage of the TETS for artificial organs with features, primary side (outside of the body) control without signal transmission system and extra power switching device and no transmission efficiency reduction .And the implementation is thought to be simple.…”

Development of a micro‐robot for endoscopes based on wireless power transfer

“…Wireless modules are adopted for communication and power supply. The stable power supplied by wireless modules is up to 480mW of DC power for the receiving coil (9,10). The micro-robot is controlled by the virtual computer (VC) program running on the PC to start entering the intestine from the anus and can go forward and backward with different velocities.…”