Advanced Spiral-wound Insulation, as described in the elpipe PCT patent application

The main patent pending position on elpipes is contained in this International patent application:

Roger Faulkner and Ron Todd, PCT patent appl. PCT/US2010/048719 “Underground Modular High-Voltage Direct Current Electric Power Transmission System,” filed September 14, 2010, published by WIPO March 17, 2011.

This patent is based on four earlier US provisional patent applications, and covers a lot of ground in its 130 pages and 84 claims. Here is an excerpt from this patent that gives the concept of a wound film insulation to reduce the thickness of insulation required:

Excerpt from September 14: PCT patent application_ABB modeling challenge.pdf

This same problem will also be addressed in an upcoming paper to be presented at the IEEE Dielectrics and Insulation Society's Electrical Insulation Conference, June 5-8, 2011:
Novel Spirally-Wound Insulation for Straight HVDC Conductors to Avoid Voltage Stress Inversion (as revised).


I expect to file a US national phase patent application based on this PCT soon; this application will be filed under USPTO's CleanTech fast track program. In addition to this main patent position, I have also filed a patent for my HVDC circuit breaker concept, which is described in this paper.