Wireless power transfer system for biomedical application: A review

Wireless power transfer system is an emerging technology that is useful to recharge the battery wirelessly for various portable and biomedical implant devices, battery free sensors, passive RF identification, near-field communications, and many others in near field region. WPT is a fundamental enabling technology which eliminates wired power connections. It is a very broad research area that has recently become applicable to implantable medical devices. Biomedical implanted devices are becoming popular in health and medical applications in a wide range of areas, such as, cardiac pacemakers, retinal prosthesis, cochlear implants, defibrillator, smart orthopedic implants, artificial hearts etc. The traditional approach of supplying power to these devices is implantable batteries, bio-fuel cell and percutaneous links. However, any battery has limited energy storage and life span similarly bio-fuel cell has low output power and percutaneous links are susceptible to infection and reliability problems. Currently, most commercial implanted devices utilize high volume, non-rechargeable batteries. These batteries inevitably need to be replaced at the end of their life span by costly surgery. In addition, bulky size of the batteries due to high energy requirement becomes an obstacle in design of compact implantable devices. The aim of this paper is to review WPT technology in biomedical Application and challenges in WPT system design. The most important advantage of wireless power transfer system is longer life span as compared to non rechargeable batteries and capability to deliver power without costly invasive surgery. In addition invasive surgery involves serious health hazards which are totally eliminated by Wireless Power Transfer System.