Capacitor-free EV onboard charger using motor winding energy
This technology repurposes the electric motor's existing copper windings as a temporary energy storage element while an electric vehicle is plugged in and charging. When AC power is converted to DC for charging, it naturally creates a pulsing ripple in the energy flow; instead of using a large, heavy capacitor to smooth that ripple, the system temporarily stores the excess energy pulses in the motor coils themselves. The motor's switching circuit periodically reverses current direction to prevent the motor from magnetizing and being damaged. The net result is that the bulky filter capacitor in the charger can be reduced by ten times or more in size, weight, and cost.
What you could build
An onboard EV battery charger design licensed to automotive OEMs or Tier 1 power electronics suppliers that eliminates the need for large filter capacitors by reusing motor windings, resulting in smaller, lighter, and cheaper charging systems.
Who in Virginia should care
Virginia-based defense and automotive electronics suppliers, as well as EV fleet operators and charging infrastructure companies in the Northern Virginia and Richmond corridors, would have interest in lighter, lower-cost onboard charging systems.
Readiness: Lab validated
Concept — described but not yet demonstrated. Lab validated — supported by experimental results in the patent. Prototype likely — the text describes a built, working embodiment.
Readiness is inferred from the patent text, not from a lab visit.
The record
- Inventors
- Khai Doan The Ngo, Hui Wang
- Granted
- March 13, 2018
- Status
- Granted patent
- Patent number
- 9914362
Ready to talk?
Virginia Tech Intellectual Properties handles licensing for this technology.
Prosim summaries are generated from public patent text and are not legal advice.