Abstract: A ground fault immune power and data delivery system for downhole sensors is connected to a downhole motor via a three-phase power cable. An AC power supply and sensor data module are electrically connected to one of two conductors (phases) at a time selected from the three conductors (phases) to provide power and data signals to the downhole sensors. If a ground fault is detected on one of the two connected phases, an isolation module isolates the grounded phase and switches to the ungrounded connected phase to continue transmitting power and data signals. A frequency of AC power supply, data communication frequencies and a switching frequency of a drive controlling the downhole motor are orthogonal to each other in order to mitigate interference. Surface-to-downhole communication can occur by adjusting voltage, frequency and/or phase of AC power supply controlled by a processor.

Abstract: An electrically powered artificial lift system includes a tubular for conveying a wellbore fluid upward and a downhole pump that urges the wellbore fluid into the tubular. A power cable conveys a three-phase power signal to the pump motor on three conductors. One of the three conductors is coupled to an internal node of a high-to-low voltage (HLV) source coupler via a low frequency blocking filter that shields the internal node from the motor power signal while conveying a sensor power signal from the internal node to the selected conductor and conveying a telemetry signal from the selected conductor and to the internal node. A similar downhole coupler couples a wye point of the motor to a downhole sensor assembly to supply the sensor power signal and to receive the telemetry signal.

Abstract: A ground fault immune power and data delivery system for downhole sensors is connected to a downhole motor via a three-phase power cable. An AC power supply and sensor data module are electrically connected to one of two conductors (phases) at a time selected from the three conductors (phases) to provide power and data signals to the downhole sensors. If a ground fault is detected on one of the two connected phases, an isolation module isolates the grounded phase and switches to the ungrounded connected phase to continue transmitting power and data signals. A frequency of AC power supply, data communication frequencies and a switching frequency of a drive controlling the downhole motor are orthogonal to each other in order to mitigate interference. Surface-to-downhole communication can occur by adjusting voltage, frequency and/or phase of AC power supply controlled by a processor.

Abstract: An electrically powered artificial lift system includes a tubular for conveying a wellbore fluid upward and a downhole pump that urges the wellbore fluid into the tubular. A power cable conveys a three-phase power signal to the pump motor on three conductors. One of the three conductors is coupled to an internal node of a high-to-low voltage (HLV) source coupler via a low frequency blocking filter that shields the internal node from the motor power signal while conveying a sensor power signal from the internal node to the selected conductor and conveying a telemetry signal from the selected conductor and to the internal node. A similar downhole coupler couples a wye point of the motor to a downhole sensor assembly to supply the sensor power signal and to receive the telemetry signal.