Abstract: A power transmission system and method for transmitting power over a three-phase power system on a multi-conductor power cable between a surface and a sub-surface location are provided. A surface system includes a power supply providing a direct current (DC) power signal to the power cable. A sub-surface system includes a downhole system coupled to a Y-point of a downhole motor. The downhole system is configured to be powered by (i) the DC power signal provided by the surface system, (ii) alternating current (AC) power drawn from the Y-point, and (iii) a combination of the DC power and the AC power. The downhole system is powered by the DC power when the power cable does not have an insulation fault, and the downhole system is powered by the AC power or the combination of the DC power and the AC power when the power cable has an insulation fault.

Abstract: A bi-directional data communications system and associated methods of high speed data communication for transferring data over a three phase power system are provided. Transmission of information uphole is performed using either sequential or simultaneous multiple frequency transmissions, selected to avoid known sources of electric noise. The frequencies are transmitted such that a combination of multiple frequencies or a pattern of frequency transmissions represents the transmitted data. Frequencies used for uphole transmission can be adaptively adjusted by downhole communication of data interpreted by the downhole unit. Digital signal processing including time and frequency domain techniques are used to decode the transmitted data.

Abstract: A power transmission system and method for transmitting power over a three-phase power system on a multi-conductor power cable between a surface and a sub-surface location are provided. A surface system includes a power supply providing a direct current (DC) power signal to the power cable. A sub-surface system includes a downhole system coupled to a Y-point of a downhole motor. The downhole system is configured to be powered by (i) the DC power signal provided by the surface system, (ii) alternating current (AC) power drawn from the Y-point, and (iii) a combination of the DC power and the AC power. The downhole system is powered by the DC power when the power cable does not have an insulation fault, and the downhole system is powered by the AC power or the combination of the DC power and the AC power when the power cable has an insulation fault.

Abstract: A data communications system and associated method of high speed data communication for transferring data over a three phase power system are provided. Transmission of information is performed using either sequential or simultaneous multiple frequency transmissions. The frequencies are transmitted such that a combination of either simultaneous multiple frequencies or a pattern of frequency transmissions represents the transmitted data. Digital signal processing including time and frequency domain techniques are used to decode the transmitted data.