Method and apparatus for supplying energy to an implant

A method for controlling wireless transmission of energy supplied to an electrically powered medical device when implanted in a patient, the method comprising powering the medical device by an internal energy receiver of the medical device, wirelessly supplying energy to said internal energy receiver by an external energy source located externally to the patient, wherein the external energy source is equipped with a primary coil from which the external energy source inductively transmits said energy to a first secondary coil in the energy receiver, the method further comprising determining, by measurements, one or more parameters related to a first coupling factor between the primary and the first secondary coil, transmitting, by the external energy source, a first amount of energy to the energy receiver for enabling detecting, by the medical device, information related to the first coupling factor, wirelessly sending feedback information related to said first coupling factor to the external energy source, receiving, by the external energy source, said feedback information from the medical device, performing, by the external energy source, a predetermined action based on said feedback information, and switching, by a first switch in the energy receiver, a connection between the first secondary coil and the medical implant on and off, in order to enable measuring of the first coupling factor when the connection is off.

A method for controlling wireless transmission of energy supplied to an electrically powered medical device when implanted in a patient, the method comprising powering the medical device by an internal energy receiver of the medical device, wirelessly supplying energy to the internal energy receiver by an external energy source be located externally to the patient, wherein the external energy source is equipped with a primary coil from which the external energy source inductively transmits said energy to a first secondary coil in the energy receiver, the method further comprising determining, by measurements, one or more parameters related to a first coupling factor between the primary and the first secondary coil, transmitting, by the external energy source, a first amount of energy to the energy receiver for enabling detecting, by the medical device, information related to the first coupling factor, wirelessly sending feedback information related to said first coupling factor to the external energy source, receiving, by the external energy source, said feedback information from the medical device, performing, by the external energy source, a predetermined action based on said feedback information, and preventing, by an electronic component connected to the first secondary coil, flow of electrical current between the first secondary coil and the medical implant during measurement of parameters related to the first coupling factor.

A method for controlling wireless transmission of energy supplied to an electrically powered medical device when implanted in a patient, the method comprising powering the medical device by an internal energy receiver of the medical device, wirelessly supplying energy to the internal energy receiver by an external energy source located externally to the patient, wherein the external energy source is equipped with a primary coil from which the external energy source inductively transmits said energy to a first secondary coil in the energy receiver, wherein the energy receiver further comprises a second secondary coil, so that the primary coil has a first coupling factor in relation to the first secondary coil and a second coupling factor in relation to the second secondary coil, with the first secondary coil being arranged to receive energy for powering the medical device and the second secondary coil being adapted to supply information related to the second coupling factor, wherein the second coupling factor has a predetermined relation to the first coupling factor, the method further comprising:

• determining, by measurements, one or more parameters related to a second coupling factor between the primary coil and the second secondary coil,
• transmitting, by the external energy source, a first amount of energy to the energy receiver for enabling the medical device, to detect, information related to the second coupling factor,
• sending wirelessly feedback information related to said second coupling factor to the external energy source, receiving, at the external energy source, said feedback information from the medical device,
• performing, by the external energy source, a predetermined action based on said feedback information, and at least one of the following;
• letting the second secondary coil be substantially without electrical load when measuring parameters related to the second coupling factor, and
• providing an electronic component connected to said second secondary coil, for preventing or substantially reducing the flow of electrical current between the second secondary coil and the medical implant during the measurements of parameters related to the second coupling factor, the method further comprising the step of;
• determining said second coupling factor, using the parameters related to the second coupling factor.