2015 年 23 巻 1 号 p. 163-170
A transcutaneous energy transmitting system (TETS) enables a cable-free supply of electric power through the skin to a ventricular assist device. This carries a lower risk of infection than cable-based power supplies because there is no skin penetration. However, the magnetic field emitted from a TETS exceeds the standard set by CISPR 11. We proposed a three-phase transcutaneous transformer that produces lower magnetic fields. The three-phase transcutaneous transformer comprises three pairs of transformers and is driven by three-phase alternating current. We measured and analyzed the magnetic field strength and its distributions with a method-of-moments-based simulator. The measurement results showed that the maximum magnetic field Hmax from a conventional transcutaneous transformer is 41.82-50.98 dBμA/m which exceeds the CISPR 11 standard level. However, Hmax from the three-phase transcutaneous transformer is 13.44-21.82 dBμA/m, which is well below the CISPR 11 standard level. It is clear that the three-phase transcutaneous transformer is a powerful way to effectively decrease the magnetic field around a TETS.
