Power System Current Measurement Using Sensor Array Techniques

• Author / Creator

  Gao, Pengfei

• Measuring current flow is an essential task for power systems. Although offering high-quality measurement results, traditional current sensing techniques share a common problem: the need for direct access to each individual conductor. The lack of an effective approach for measuring the currents in a group of bundled, enclosed or inaccessible conductors has resulted in the needs for new current measurement techniques.This thesis proposes methods to address three multi-conductor current measurement problems utilizing the sensor-array-based techniques. The first technique, including two main components, is designed specifically for measuring the currents entering the North America homes. One component is a sensor array deployed near the conductors of interest to measure the magnetic fields produced by the currents. The other component is a sensor calibrator, connecting to the conductors at a location downstream the sensor array. The relationship between the sensor outputs and the conductor currents is derived by an active calibration scheme, making it feasible to determine the currents through the sensor measurements non-intrusively. For the inaccessible conductors that are difficult to apply the active calibration scheme, this thesis proposes to use a magnetic sensor array to solve the conductor positions and their currents mathematically. The sensor parameters are made known to the measurement system model through an off-line calibration method. A prototype device has been developed to measure different types of industrial cables.Measuring the Zero-sequence current of overhead power conductors has been a challenging problem but is important to many power quality studies. This thesis presents a technique that can measure the overhead line zero-sequence current remotely, regardless the existence of the neutral conductor. The proposed technique is adaptive to different overhead line configurations and does not require any input of the line parameters. The promising results from actual field tests indicate that the proposed zero-sequence current sensor array has a potential to become a powerful tool for the electric power industry.

• Subjects / Keywords

  • Current measurement, magnetic field sensor array

• Graduation date

  Spring 2018

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/R37941890

• License

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