This paper presents a fault location technique for three-terminal hybrid AC transmission lines with one off-service line branch by using synchrophasor data obtained from buses which are connected to in-service line branches. The proposed method adopts the two-terminal fault location technique to identify the faulted line branch and locate the fault point when a fault exists on the in-service line branch. Contrarily, if a fault exists on the off-service line branch, the apparent reactance that is obtained from synchronized voltage and current phasor sets of the junction point P, and sequence networks are both chosen to calculate the exact fault point. The performance evaluation shows that the proposed idea has high accuracy under different fault types and resistance.

In a power system, the transmission network is the backbone of electricity delivery from power plants to load centers; hence it becomes a critical issue for electrical engineers to shorten the service restoration time after a fault occurrence on the transmission line. This application paper integrates the two- and three-terminal hybrid transmission line fault location algorithms based on synchronized phasor measurements into the proposed cloud-computing based fault location system to inspect the feasibility and practicality of our algorithms for the real transmission-line incidents. The computing results are respectively performed via Google Map® for authorized personal computers and the developed application (APP) for intelligent mobile devices to assist engineers in acquiring the fault-event information immediately as well as in figuring out the fault position intuitively and quickly due to its visualization and navigation. Last but not the least, the suggested fault location system has already been applied to the practical 345 kV and 161 kV transmission networks of Taiwan Power Company (TPC) for achieving the combination of theory and practice. Up to the present, the proposed system still yields excellent performance verified by realistic fault data.

This article presents an innovative fault location algorithm utilizing an unsynchronized waveform measured from independent intelligent electronic devices (IEDs) installed in individual power substations without available wired or wireless communication link between the IEDs to establish the common timestamp required for the IEDs to record waveform data synchronously. The proposed idea is developed based on the positive-sequence waveform phasors with the superimposed-signal concept. A novel fault position indicator is proposed to yield an exact solution without being affected by unsynchronized measurement information because the unsynchronized-angle estimation is needless. Besides, the proposed idea does not require any assumptions, such as fault impedance, and is also free from computational complexity in as much as neither iterative operations nor fault type selections are needed. Last but not least, an extensive series of simulations and two field test results from the fault events of Taiwan Power Company have been presented to demonstrate the accuracy and practicality of the suggested technique.

The inclination sensor is an indispensable sensing component in numerous objects’ detection and measurement, including industries, edifice structures, and other things. The current study is the first to offer a demonstration for concurrently measuring the inclination and whole-fiber temperature change by the Raman-distributed temperature sensing (RDTS) technique. Optical fibers are wound neatly and orderly on cylinders, or different wound fiber laps are placed in irregular order in the same narrow, neatly identical spaces of different heights. One section of the winding fiber submerged in water will float out of the water when the cylinder tilts, causing a temperature change that enables the inclination to be monitored. This design can assess changes in water level in addition to using the RDTS to determine tilt by identifying the temperature differential between water and air. It can recognize the difference in the tilt angle of 0.696° and the water level of 1 cm. The proposed RDTS inclination measurement system breaks the limitations of previous inclination sensors because it can simultaneously detect both temperature and water level parameters without the additional sensing device required. Also, it supports multi-point inclination measurements, functions underwater, can be integrated into hydrology-related monitoring systems, and can be monitored remotely.

This paper presents a fault location technique for homogeneous ring-topology power transmission systems using synchrophasors sensed from the instruments in the power Internet of Things (IoT), such as Global Positioning System (GPS) based Phasor Measurement Units (PMUs) or Intelligent Electronic Devices (IEDs) with embedded GPS. Moreover, with a view to reducing the influence of measurement errors on fault location estimation, minimum demands for GPS-based equipment and Capacitor Voltage Transformer (CVT)/Current Transformer (CT) transducers are also considered when deriving the proposed algorithm. A unique fault locator is thus developed to recognize the faulted line branch as well as pinpoint the fault position at the same time. Not only can the proposed method avoid iterative operations, but it is also free from the problems of multiple solutions, fault type selections, and fault-path/source impedance assumptions. Last but not the least, extensive simulations considering 161 kV overhead-line parameters of Taiwan Power Company (Taipower) and actual non-ideal sensing/measurement phenomena are conducted to demonstrate the performance and effectiveness of the suggested idea.