WIRELESS CHARGING SYSTEM for ELECTRIC VEHICLES:
Electric vehicle charging technology can be divided into two methods: conductive way using an electrical wire and wireless charging. Up to the present time, conductive charging technologies have complex issues related to a physical wire plugging to an electric outlet, charging time frame and safety concern.
Our research team has developed a wireless fast charging system that is capable of charging an electric vehicle while it is stationery or it is moving. The CTI wireless charging system is safe, fast, and with expected efficiency exceeding 90%
The wireless charging system will replace the conductive way, in a similar manner that the wireless telephone communication has drastically replaced the copper wire network that was in existence over the past century.
Figure 1: Nissan Leaf with a wireless charging system
Figure 2: AMPTRAN Electric Car with a wireless charging system
The main objective if the research project is to develop Pulse Transmission Nanocomposite Magnetic Resonant Coupling, which will enable on-the-road wireless dynamic charging while vehicle is in motion.
The Pulse Transmission Nanocomposite Magnetic Resonant Coupling (PNMRC) is comprised of three major components in conjunction with the electric vehicle: a power inverter, power nanocomposite emitting coils, and nanocomposite receiving coils mounted underneath the electric vehicle.
The proposed Pulse Transmission Nanocomposite Magnetic Coupling Technology (PNMRC) offers 2 innovative approaches to solve the common problems of wireless transfer of energy via magnetic coupling technology, which are instability and energy loss over a prolonged period of time.
1. The first innovative approach is using the pulse transmission mechanism to control the switching frequency and break time on-demand.
2. The second approach is the development of novel nanocomposite Carbon- Copper Coil. Due to their enhanced Signal to Noise Ratio properties, the nanocomposite coils can result in significant improvements in efficiency of wireless electrical charging for electric vehicles.
In the PNMRC system, related parameters (voltage amplitude, frequency and duty cycle , etc.) of the pulse signal can be adjusted to control the switching frequency and break time, thus makes the power supply of high-frequency pulse-driven signal, timely provides energy to the emitting resonant coil loop. Energy is aggregated continuously at the receiving inductance coil through the strong coupled magnetic resonances, and then is delivered to the load. The pulse transmission mechanism enable intermittent supply of electrical energy at high voltage and high frequency on-demand with the highest efficiency, because energy is only supplied on-demand in pulse signal over a large number of transmitting coil pads on the roadway.
The receiving coils are constructed with a locally ballistic electrical conductor such as carbon-copper nanocomposite variations whose resistance does not increase significantly with length over appropriate local length scales. Due to their enhanced Signal to Noise Ratio properties, the nanocomposite coils can result in significant improvements in efficiency of wireless electrical charging for electric vehicles. The nanocomposite coils include metal conductors deposited on ends of the transmitting and receiving coils.
Figure 3: Power Pad Construction
The important underlining concept of the Pulse Nanocomposite Magnetic Resonant Coupling is the capability to reduce energy loss by minimizing the leakage field with pulse transmission signals and carefully selecting the design variables of the cables, coils and resonant frequency.
The wireless charging is non-radiative power transfer uses a magnetic near field, with no-effect to human being or animals. It is totally safe and simple to operate.
With PTMRC System embedded on the roadway enables dynamic charging to an electric vehicle in motion travelling non-stop over a long distance, without stopping and waiting for charging or refueling. This is a unique feature that will solve a major obstacle of range limitation and will expedite the deployment of electric vehicles in a new frontier of freedom for electrified transportation.
For more information, please contact Lloyd L. Tran, principal inevstigator by completing an online contact form. Thank you.
NASA Ames Research Center
P.O. Box 151
Moffett Field, CA 94035