Abstract:Wireless energy transfer urethral valve is a kind of auxiliary urinary control device,which is designed to simulate the function of the urethral sphincter.In order to evaluate its safety after implantation in the human body,3D models of human tissue layers were established using HFSS software.Specific absorption rate (SAR) and current density values of all tissue layers were calculated in the frequency range from 100 kHz to 1 000 kHz when the distance between wireless energy transfer coils was 15 mm and 20 mm.The changes of SAR value and current density of each tissue layer with the distance of wireless energy transmission coils and operating frequency were analyzed.The simulation results show that the SAR value and current density of each tissue layer increase with the increase of operating frequency,the SAR value and current density of the skin layer and fat layer increase with the increase of coil distance,while the SAR value and current density of muscle layer decrease with the increase of coil distance.The maximum SAR value and current density value are 8.77×10-11 W/kg and 433.5 μA/m2,respectively,which are far less than the safety limit and meet the requirements of safe use.