Combined power transmission and heating systems and method of operating the same

A fluid transportation system comprising:

• an electrical load;
• a fluid transportation device electrically coupled to said electrical load, said fluid transportation device configured to transport a fluid;
• and
• a direct current (DC) power transmission and heating system electrically coupled to said electrical load, said DC power transmission and heating system comprising:
• a rectifier station configured to generate a DC link current;
• a downstream converter station positioned remotely from said rectifier station, said downstream converter station configured to generate power supplied to said electrical load using at least a portion of the DC link current;
• a return conductor coupled to said rectifier station and said downstream converter station, said return conductor configured to:
• transmit a return current from said downstream converter station to said rectifier station;
• generate heat from resistive losses induced by the return current;
• and
• conduct the heat generated by the return current to a fluid being transported from a proximity of said downstream converter station to a proximity of said rectifier station;
• and
• wherein said downstream converter station further comprises a bypass device configured to selectively control an amount of load current transmitted to said electrical load and an amount of bypass current transmitted around said electrical load to said return conductor.

A method of operating a combined DC power transmission and heating system, said method comprising:

• generating a DC link current using a rectifier station;
• receiving the DC link current at a downstream converter station;
• controlling, by the downstream converter station, power supplied to an electrical load using the DC link current;
• transmitting, by the downstream converter station, a return current to the rectifier station through a return conductor;
• generating, by the return conductor, heat through resistive losses induced by the return current;
• conducting the heat generated by the return current to a fluid being transported from a proximity of the downstream converter station to a proximity of the rectifier station;
• and
• wherein controlling power supplied to at the electrical load includes:
• selectively controlling an amount of load current transmitted to the electrical load;
• and
• selectively controlling an amount of bypass current transmitted around the electrical load to the return conductor.