Surface mountable wireless power transmitter for transmission at extended range

A surface mountable power transmitter for wireless power transfer at an operating frequency selected from a range of about 87 kilohertz (kHz) to about 205 kHz, the surface mountable power transmitter configured to be mounted on an underside of a structural surface, the power transmitter comprising:

• a control and communications unit;
• an inverter circuit configured to receive input power and convert the input power to a power signal;
• a transmitter antenna, the transmitter antenna including:
• a coil structure configured to transmit the power signal to a device having a power receiver, the coil structure comprising at least one layer of Litz wire, wherein the coil structure has a top surface, a bottom surface, and a side surface;
• and
• a ferrite shielding structure comprising a magnetic core having an outer face, a magnetic backing having a top face, and a magnetic ring having an inner face, and the ferrite shielding structure having a cavity defined by the outer face of the magnetic core, the top face of the magnetic backing, and the inner face of the magnetic ring, the cavity configured such that the ferrite shielding structure substantially surrounds at least a portion of the bottom surface of the coil structure and at least a portion of the side surface of the coil structure, and wherein the bottom surface of the coil structure and the top face of the magnetic backing are separated by a separation distance;
• and
• a surface mountable housing, the surface mountable housing connected to, at least, the transmitter antenna, and the surface mountable housing including a connector system configured for use to mount, at least, the transmitter antenna to the underside of the structural surface such that the transmitter antenna is configured to couple with a receiver antenna of the power receiver when the receiver antenna is proximate to a top side of the structural surface,
• wherein, when the surface mountable power transmitter is mounted to the underside of the structural surface, the top surface of the coil structure has a first height and the top side of the structural surface has a second height, wherein the second height is greater than the first height by a gap distance in a range of about 8 millimeters (mm) to about 15 mm.

A surface mountable housing for a power transmitter for wireless power transfer at an operating frequency selected from a range of about 87 kilohertz (kHz) to about 205 kHz, the power transmitter including, at least, a transmitter antenna comprising a coil having a side surface and a bottom surface substantially surrounded by a ferrite core, the surface mountable housing comprising:

• a connector system configured for use to mount, at least, the transmitter antenna to an underside of a structural surface, such that the transmitter antenna is configured to couple with a receiver antenna of a power receiver when the receiver antenna is proximate to a top side of the structural surface;
• a heat sink comprising an outer side wall and a bottom wall defining a recess, the heat sink configured to rest, at least in part, below the transmitter antenna, when the power transmitter is mounted to the structural surface, and configured to direct heat generated by the power transmitter away from the structural surface;
• and
• an antenna housing comprising an outer face, a top face, an inner face, and a bottom face, the antenna housing positioned within the recess of the heat sink such that the outer side wall of the heat sink substantially surrounds the outer face of the antenna housing, wherein the inner face of the antenna housing substantially surrounds a side wall of the ferrite core of the transmitter antenna, the antenna housing connected to the heat sink and positioned between the heat sink and the structural surface,
• wherein, when the transmitter antenna is mounted to the underside of the structural surface, a top surface of the transmitter antenna has a first height and the top side of the structural surface has a second height, wherein the second height is greater than the first height by a gap distance in a range of 8 millimeters (mm) to 15 mm;
• and
• a transmitter electronic circuit board that is positioned within the recess of the heat sink below the bottom face of the antenna housing and below a bottom wall of the ferrite core of the transmitter antenna and above the bottom wall of the heat sink,
• wherein the connector system connects the heat sink to the antenna housing through at least a portion of the transmitter electronic circuit board when the surface mountable housing is mounted to the underside of the structural surface.