Contactless Energy Transfer - Timeline of Wireless Power

Timeline of Wireless Power

• 1826: André-Marie Ampère develops Ampère's circuital law showing that electric current produces a magnetic field.
• 1831: Michael Faraday develops Faraday's law of induction describing the electromagnetic force induced in a conductor by a time-varying magnetic flux.
• 1836: Nicholas Callan invents the electrical transformer, also known as the induction coil.
• 1865: James Clerk Maxwell synthesizes the previous observations, experiments and equations of electricity, magnetism and optics into a consistent theory and mathematically models the behavior of electromagnetic radiation in a set of partial differential equations known as Maxwell's equations.
• 1888: Heinrich Rudolf Hertz confirms the existence of electromagnetic radiation. Hertz’s "apparatus for generating electromagnetic waves" was a VHF or UHF "radio wave" spark gap transmitter.
• 1891: Tesla patents a practical method for the efficient production of high-power radio frequency electric current, U.S. Patent 447,920, "Method of Operating Arc-Lamps."
• 1891: Tesla demonstrates wireless energy transmission by means of electrostatic induction using a high-tension induction coil before the American Institute of Electrical Engineers at Columbia College.
• 1893: Tesla demonstrates the wireless illumination of phosphorescent lamps of his design at the World's Columbian Exposition in Chicago.
• 1893: Tesla publicly demonstrates wireless power and proposes the wireless transmission of signals before a meeting of the National Electric Light Association in St. Louis.
• 1894: Tesla lights incandescent lamps wirelessly at the 35 South Fifth Avenue laboratory in New York City by means of "electro-dynamic induction" or resonant inductive coupling.
• 1894: Hutin & LeBlanc, espouse long held view that inductive energy transfer should be possible, they received U.S. Patent # 527,857 describing a system for power transmission at 3 kHz.
• 1894: Jagdish Chandra Bose rings a bell at a distance using electromagnetic waves and also ignites gunpowder, showing that communications signals can be sent without using wires.
• 1895: Marconi demonstrates radio transmission over a distance of 1.5 miles. Developed Marconi's Law.
• 1896: Tesla demonstrates wireless transmission over a distance of about 48 kilometres (30 mi).
• 1897: Tesla files his first patent application dealing specifically with wireless transmission.
• 1899: Tesla continues wireless power transmission research in Colorado Springs and writes, "the inferiority of the induction method would appear immense as compared with the disturbed charge of ground and air method."
• 1902: Nikola Tesla vs. Reginald Fessenden – U.S. Patent Interference No. 21,701, System of Signaling (wireless); wireless power transmission, time and frequency domain spread spectrum telecommunications, electronic logic gates in general.
• 1904: At the St. Louis World's Fair, a prize is offered for a successful attempt to drive a 0.1 horsepower (75 W) airship motor by energy transmitted through space at a distance of at least 100 feet (30 m).
• 1916: Tesla states, "In my system, you should free yourself of the idea that there is radiation, that energy is radiated. It is not radiated; it is conserved."
• 1917: The Wardenclyffe tower is demolished.

• 1926: Shintaro Uda and Hidetsugu Yagi publish their first paper on Uda's "tuned high-gain directional array" better known as the Yagi antenna.

• 1961: William C. Brown publishes an article exploring possibilities of microwave power transmission.
• 1968: Peter Glaser proposes wirelessly transmitting solar energy captured in space using "Powerbeaming" technology. This is usually recognized as the first description of a solar power satellite.
• 1973: The world's first passive RFID system is demonstrated at Los-Alamos National Lab.
• 1975: Goldstone Deep Space Communications Complex does experiments in the tens of kilowatts.
• 1998: RFID tags are powered by electrodynamic induction over a few feet.
• 1999: Prof. Shu Yuen (Ron) Hui and Mr. S.C. Tang file a patent on "Coreless Printed-Circuit-Board (PCB) transformers and operating techniques", which form the basis for future planar charging surface with "vertical flux" leaving the planar surface. The circuit uses resonant circuits for wireless power transfer. EP(GB)0935263B
• 2000: Prof. Shu Yuen (Ron) Hui invent a planar wireless charging pad using the "vertical flux" approach and resonant power transfer for charging portable consumer electronic products. A patent is filed on "Apparatus and method of an inductive battery charger,” PCT Patent PCT/AU03/00 721, 2000.
• 2001 Prof. Shu Yuen (Ron) Hui and Dr. S.C. Tang file a patent on "Planar Printed-Circuit-Board Transformers with Effective Electromagnetic Interference (EMI) Shielding". The EM shield consists of a thin layer of ferrite and a thin layer of copper sheet. It enables the underneath of the future wireless charging pads to be shielded with a thin EM shield structure with thickness of typically 0.7mm or less. Patent: US6,501,364.
• 2001: Prof. Ron Hui's team demonstrate that the coreless PCB transformer can transmit power close to 100W in ‘A low-profile low-power converter with coreless PCB isolation transformer, IEEE Transactions on Power Electronics, Volume: 16 Issue: 3, May 2001. A team of Philips Research Center Aachen, led by Dr. Eberhard Waffenschmidt, use it to power an 100W lighting device in their paper "Size advantage of coreless transformers in the MHz range" in the European Power Electronics Conference in Graz.
• 2002: Prof. Shu Yuen (Ron) Hui extends the planar wireless charging pad concept using the vertical flux approach to incorporate free-positioning feature for multiple loads. This is achieved by using a multilayer planar winding array structure. Patent were granted as "Planar Inductive Battery Charger", GB2389720 and GB 2389767.
• 2005: Prof. Shu Yuen (Ron) Hui and Dr. W.C. Ho publish their work in the IEEE Transactions on a planar wireless charging platform with free-positioning feature. The planar wireless charging pad is able to charge several loads simultaneously on a flat surface.
• 2007: A localized charging technique is reported by Dr. Xun Liu and Prof. Ron Hui for the wireless charging pad with free-positioning feature. With the aid of the double-layer EM shields enclosing the transmitter and receiver coils, the localized charging selects the right transmitter coil so as to minimize flux leakage and human exposure to radiation.
• 2007: Using electrodynamic induction the WiTricity physics research group, led by Prof. Marin Soljacic at MIT, wirelessly power a 60W light bulb with 40% efficiency at a 2 metres (6.6 ft) distance with two 60 cm-diameter coils.
• 2008: Bombardier offers a new wireless power transmission product PRIMOVE, a system for use on trams and light-rail vehicles.
• 2008: Intel reproduces the original 1894 implementation of electrodynamic induction and Prof. John Boys group's 1988 follow-up experiments by wirelessly powering a nearby light bulb with 75% efficiency.
• 2008: Greg Leyh and Mike Kennan of the Nevada Lightning Laboratory publish a paper on the disturbed charge of ground and air method of wireless power transmission with circuit simulations and test results showing an efficiency greater than can be obtained using the electrodynamic induction method.
• 2009: Palm (now a division of HP) launches the Palm Pre smartphone with the Palm Touchstone wireless charger.
• 2009: A Consortium of interested companies called the Wireless Power Consortium announce they are nearing completion for a new industry standard for low-power (which is eventually published in August 2010) inductive charging.

• 2009: An Ex approved Torch and Charger aimed at the offshore market is introduced. This product is developed by Wireless Power & Communication, a Norway based company.
• 2009: A simple analytical electrical model of electrodynamic induction power transmission is proposed and applied to a wireless power transfer system for implantable devices.
• 2009: Lasermotive uses diode laser to win $900k NASA prize in power beaming, breaking several world records in power and distance, by transmitting over a kilowatt more than several hundred meters.
• 2009: Sony shows a wireless electrodynamic-induction powered TV set, 60 W over 50 cm
• 2010: Haier Group debuts “the world's first” completely wireless LCD television at CES 2010 based on Prof. Marin Soljacic's follow-up research on the 1894 electrodynamic induction wireless energy transmission method and the Wireless Home Digital Interface (WHDI).
• 2010: System On Chip (SoC) group in University of British Columbia develops a highly efficient wireless power transmission systems using 4-coils. The design is optimized for implantable applications and power transfer efficiency of 82% is achieved.
• 2012: "Bioelectromagnetics and Implantable Devices" group in University of Utah, USA develops an efficient multi-Coil telemetry system for power and data transfer in biomedical Implants. Design approach is extendable to other industrial "smart" wireless power transfer system. Proposed multi-coil based telemetry system achieves more than twice power transfer efficiency and higher tunable frequency bandwidth as compared to its equivalent two-coil design. Based on circuit theory, analytical formulation is proposed to optimize the design for maximum power transfer, frequency bandwidth and power transfer efficiency.
• 2012: Christopher Tucker and Kevin Warwick of the University of Reading, UK develop a highly-efficient, compact power transfer system safe for use in human proximity. The design is simple and uses only a few components to generate stable currents for biomedical implants. It resulted from research that directly attempted to extend Tesla’s 1897 wireless power work.