Patent application number | Description | Published |
20120142537 | SUPERCONDUCTING DIRECT CURRENT TRANSMISSION SYSTEM - A DC superconducting coaxial transmission system provides electrical transmission of 5,000 megawatts of energy while simultaneously delivering liquid hydrogen. The transmission system includes a coaxial transmission segment including an inner superconductor, an outer superconductor disposed in surrounding relation to the inner conductor, and a dielectric insulator disposed between the inner superconductor and the outer superconductor. Liquid hydrogen surrounds the superconductors. Three phase transformers and poly phase rectifier/inverters provide a DC voltage source to the superconductors from the electrical grid. In one embodiment, a switching circuit connected between the voltage source and the superconductor injects a cancellation current component into the direct current flow. The cancellation current component is polarized to flow in a direction opposite to the direct current flow to produce a current zero, thus enabling safe interruption of the high DC current while minimizing the magnitude of transient voltages during switching. | 06-07-2012 |
20140309117 | SUPERCONDUCTING DIRECT CURRENT TRANSMISSION SYSTEM - A DC superconducting coaxial transmission system provides electrical transmission of 5,000 megawatts of energy while simultaneously delivering liquid hydrogen. The transmission system includes a coaxial transmission segment including an inner superconductor, an outer superconductor disposed in surrounding relation to the inner conductor, and a dielectric insulator disposed between the inner superconductor and the outer superconductor. Liquid hydrogen surrounds the superconductors. Three phase transformers and poly phase rectifier/inverters provide a DC voltage source to the superconductors from the electrical grid. In one embodiment, a switching circuit connected between the voltage source and the superconductor injects a cancellation current component into the direct current flow. The cancellation current component is polarized to flow in a direction opposite to the direct current flow to produce a current zero, thus enabling safe interruption of the high DC current while minimizing the magnitude of transient voltages during switching. | 10-16-2014 |
20140376132 | SYSTEM AND METHOD TO INTERRUPT A DC CURRENT IN A HIGH VOLTAGE CIRCUIT BY USE OF AN AC CIRCUIT BREAKER - An electrical circuit to interrupt a DC current includes a bypass switch and an AC high voltage breaker which includes interrupters that are rated for carrying a current having a value of the DC current for a period of time less than or equal to continuous duty. The first interrupter is electrically coupled in parallel with the bypass switch. A making switch causes a cancellation current to flow from an energy source through the second interrupter, and through the first interrupter, in addition to the DC current. The AC high voltage breaker is adapted to a DC service as the DC current in addition to the cancellation current causes an arc quench which allows the AC high voltage breaker to cause the interruption of the DC current in the electrical circuit. A method for interrupting a DC current flowing in an AC high voltage circuit breaker is also described. | 12-25-2014 |