Bombardier's PRIMOVE technology can rapidly charge batteries or super capacitors in trolleys, buses, trucks, taxis, and even cars either while stopped or in motion. Operating like a transformer, electricity is transferred inductively from cables located under the road surface to equipment installed under the vehicle.
The induction coil under the road or track carries high-frequency alternating current creating a magnetic field. This field induces a voltage in the inductive pick-up under the vehicle. An inverter converts the alternating current from the pick-up into direct current for charging the batteries on buses, trucks, and cars, or the high-performance capacitors in Bombardier's MITRAC Energy Saver used for trams or trolleys.
The Vehicle Detection and Segment Control antenna detects when a PRIMOVE-equipped vehicle is above the segment, and then switches that segment on. The system is only energized when it’s completely covered by a vehicle. Segments otherwise remain inactive to comply with electromagnetic interference protection requirements. When energized, magnetic shielding under the primary winding prevents electromagnetic interference.
PRIMOVE eliminates the need for unsightly overhead power wires for electric buses in urban areas. While charging can be done while loading and unloading passengers, it can also be done while a vehicle is moving so stops and long waits are not necessary. The same infrastructure can be used for all types of vehicles. Reliable operation is ensured even under adverse weather with snow, rain, ice, or water on the ground.
Having successfully demonstrated the PRIMOVE technology with a Bombardier low floor tram in Augsburg, Germany, Bombardier is testing the technology with a bus on a 125-meter stretch of road in Lommel, Belgium. It plans to test it with cars this summer.
Recently, Bombardier launched its PrimoveCity program to provide easy urban mobility for all types of electric vehicles. This includes the establishment of a new center of excellence located at Bombardier’s engineering and manufacturing site in Mannheim, Germany. It is building an advanced testing and development facility that will open in September 2011. Bombardier does not manufacture components, but license the technology to other manufacturers.
Boston-based WiTricity Corp. is also developing a somewhat similar wireless charging system using resonance rather than electromagnetic induction to transfer electrical energy. Charging occurs while a plug-in hybrid or electric vehicle, equipped with a power capture resonator, is parked in the vicinity of a power source resonator. This could be located, for example, in a home garage or public parking facility. Resonance charging does not require contact between the transmitting and receiving units.
Resonance can charge battery-powered vehicles at a rates comparable to most home-based chargers, from two to eight hours depending on the battery size. According to WiTricity, resonance is more efficient than inductance charging with a maximum efficiency claimed to be around 95 percent. Both Toyota and automotive supplier Delphi are collaborating with WiTricity to accelerate development of the technology and to potentially market this wireless charging system for EVs.