Abstract: To characterize an electrical cable that is deployed in a well, a voltage input is applied to the electrical cable at an earth surface location, where the well extends from the earth surface location. A current response resulting from the voltage input is measured at the earth surface location. At least one parameter of the electrical cable is computed according to the measured current response.

Abstract: A wireline telemetry system and method of transmitting data on multiple carrier frequencies. The system and method adjust power level and number of bits-per-carrier to optimally or near-optimally utilize the capacity of the wireline cable. Due to the nature of wireline telemetry the overall power level is restricted only by the output capability of the downhole telemetry cartridge and the input power restrictions of the uphole telemetry unit receiver. The optimal power level is determined during a training sequence and is a function of such factors as cable length, cable material, cable temperature and cable geometry. The uplink and downlink transmission are executed using different modulation techniques.

Abstract: An electrical cable includes insulated primary conductors and at least one insulated secondary conductor, which extend along the cable. The primary conductors define interstitial spaces between adjacent primary conductors, and the primary conductors have approximately the same diameter. The primary conductors include power conductors and a telemetric conductor. The secondary conductor(s) each have a diameter that is smaller than each of the diameters of the primary conductors, and each secondary conductor is at least partially nested in one of the interstitial spaces. The electrical cable may include at least one fiber optic line.

Abstract: To characterize an electrical cable that is deployed in a well, a voltage input is applied to the electrical cable at an earth surface location, where the well extends from the earth surface location. A current response resulting from the voltage input is measured at the earth surface location. At least one parameter of the electrical cable is computed according to the measured current response.

Abstract: An apparatus includes a transmission line for deployment in a well, and a driver to transmit signals over the transmission line. The driver includes a field-effect transistor, and an operational amplifier to control the field-effect transistor, where the operational amplifier and field-effect transistor cooperate to form a voltage-to-current converter.

Abstract: To characterize an electrical cable that is deployed in a well, a voltage input is applied to the electrical cable at an earth surface location, where the well extends from the earth surface location. A current response resulting from the voltage input is measured at the earth surface location. At least one parameter of the electrical cable is computed according to the measured current response.

Abstract: To characterize an electrical cable that is deployed in a well, a voltage input is applied to the electrical cable at an earth surface location, where the well extends from the earth surface location. A current response resulting from the voltage input is measured at the earth surface location. At least one parameter of the electrical cable is computed according to the measured current response.

Abstract: An electrical cable includes insulated primary conductors and at least one insulated secondary conductor, which extend along the cable. The primary conductors define interstitial spaces between adjacent primary conductors, and the primary conductors have approximately the same diameter. The primary conductors include power conductors and a telemetric conductor. The secondary conductor(s) each have a diameter that is smaller than each of the diameters of the primary conductors, and each secondary conductor is at least partially nested in one of the interstitial spaces. The electrical cable may include at least one fiber optic line.

Abstract: A wireline logging assembly includes a cable having primary conductors, secondary conductors, and a central conductor. A first power source excites the primary conductors using a first propagation mode. A first telemetry transceiver excites the primary conductors using a second propagation mode orthogonal to the first mode. A second power source excites the secondary conductors and a second telemetry transceiver excites the central conductor. In one embodiment, the diameter of the primary conductors is greater than a diameter of the secondary conductors. The primary conductor includes four primary conductors symmetrically positioned around the center conductor and the secondary conductors include a secondary conductor positioned in the interstice between each pair of adjacent primary conductors.

Abstract: A wireline logging assembly includes a cable having primary conductors, secondary conductors, and a central conductor. A first power source excites the primary conductors using a first propagation mode. A first telemetry transceiver excites the primary conductors using a second propagation mode orthogonal to the first mode. A second power source excites the secondary conductors and a second telemetry transceiver excites the central conductor. In one embodiment, the diameter of the primary conductors is greater than a diameter of the secondary conductors. The primary conductor includes four primary conductors symmetrically positioned around the center conductor and the secondary conductors include a secondary conductor positioned in the interstice between each pair of adjacent primary conductors.

Abstract: A method and system for providing power to a wireline logging system includes a rectifier section operable to receive an AC input signal and generate a first DC power signal as an output. A converter section cascadedly coupled to the rectifier section converts the first DC power signal to a second DC power signal. An inverter section cascadedly coupled to the converter section is operable to generate an output power signal providing power to a system in response to receiving the second DC power signal. A control section is coupled to the rectifier section, the converter section, the inverter section and a communications link. The communications link is operable to receive information describing waveforms for the output power signal. The control section is operable to receive the information and control a corresponding section to generate the waveforms in response to receiving the information.

Abstract: A method and system for providing power to a wireline logging system includes a rectifier section operable to receive an AC input signal and generate a first DC power signal as an output. A converter section cascadedly coupled to the rectifier section converts the first DC power signal to a second DC power signal. An inverter section cascadedly coupled to the converter section is operable to generate an output power signal providing power to a system in response to receiving the second DC power signal. A control section is coupled to the rectifier section, the converter section, the inverter section and a communications link. The communications link is operable to receive information describing waveforms for the output power signal. The control section is operable to receive the information and control a corresponding section to generate the waveforms in response to receiving the information.

Abstract: A wireline logging method including estimating a data rate requirement associated with a tool string to be connected to a wireline cable and determining an operating characteristic of a wireline cable at the surface. The operating characteristic is indicative of the wireline cable's data rate capacity. Before inserting the wireline cable into a well bore, a down hole value of the operating characteristic is modeled and a down hole data rate capacity is derived based thereon. Upon determining that the estimated data rate requirement does not match the down hole data rate capacity, the tool string is modified to remove or add tools to the tools string to match the tool strings data rate requirements with the estimated data rate capacity of the tool string and cable.

Abstract: The disclosure describes a system and method for dynamically matching a source impedance to a load impedance or the complex conjugate of the load impedance. An embodiment of the present invention is a device for active impedance matching comprising a current driver having an output connected to a load, means for detecting an output voltage from the current driver to the load, means for scaling the detected output voltage by a scaling value, and means for subtracting a value representing the scaled detected output current from an input signal of the voltage driver.

Abstract: The disclosure describes a system and method for dynamically matching a source impedance to a load impedance or the complex conjugate of the load impedance. An embodiment of the present invention is a device for active impedance matching comprising a current driver having an output connected to a load, means for detecting an output voltage from the current driver to the load, means for scaling the detected output voltage by a scaling value, and means for subtracting a value representing the scaled detected output current from an input signal of the voltage driver.

Abstract: Dynamic matching of a source impedance to a load impedance or the complex conjugate of the load impedance. An embodiment of the invention is a device for active impedance matching comprising a voltage driver having an output connected to a load, means for detecting an output current from the voltage driver to the load, means for scaling the detected output current by a scaling value, and means for subtracting a value representing the scaled detected output current from an input signal of the voltage driver. Another embodiment is a device for active impedance matching comprising a current driver having an output connected to a load, means for detecting an output voltage from the current driver to the load, means for scaling the detected output voltage by a scaling value, and means for subtracting a value representing the scaled detected output voltage from an input signal of the current driver.

Abstract: Dynamic matching of a source impedance to a load impedance or the complex conjugate of the load impedance. An embodiment of the invention is a device for active impedance matching comprising a voltage driver having an output connected to a load, means for detecting an output current from the voltage driver to the load, means for scaling the detected output current by a scaling value, and means for subtracting a value representing the scaled detected output current from an input signal of the voltage driver. Another embodiment is a device for active impedance matching comprising a current driver having an output connected to a load, means for detecting an output voltage from the current driver to the load, means for scaling the detected output voltage by a scaling value, and means for subtracting a value representing the scaled detected output voltage from an input signal of the current driver.

Abstract: A cable that has a longitudinal axis and includes four insulated primary conductors which extend along the cable and define interstices between adjacent primary conductors. At least one insulated secondary conductor has a wire gauge smaller than the primary conductors and extends about the longitudinal axis of the cable. The at least one secondary conductor is at least partially nested in one of the interstices. An armor shield surrounds the primary and secondary conductors.

Abstract: The invention relates to an electrical connector for transmitting electrical signals between the outside and the inside of a well having a well head (20) terminated by a valve assembly (10). The connector comprises at least two inductively coupled electrical coils (1A, 1B; 5A, 5B) whose respective winding axes are aligned with the axis (zz') of the well head. The coils are integrated in the fluid connector interconnecting the valve assembly and the well head, with one of the coils being releasably fixed to the valve assembly (10) while the other coil is releasably fixed to the well head (20).