Measurement and information systems

Detection, localization and interpretation of partial discharge.: In order to detect, localize and interpret a partial discharge occurring in a partial discharge site along an electrical equipment, two measurement probes and a synchronization probe are installed along the electrical equipment. The measurement probes detect pulses travelling in the electrical equipment while the synchronization probe detects a phase angle in the electrical equipment and is usable for calibration purposes. A control unit receives the signals sensed by the probes and conditions them. Digital processings applied on the conditioned signals, involving their correlation, a time-frequency distribution and a form factor estimation, allows establishing a diagnosis indicating a detection of a partial discharge and its localization along the electrical equipment.

No. Application, patent (CA) : CA 2608216
No. Application, patent (USA) : 8,126,664
Localisation of a defect on a section of a dead electrical line.: A localisation of a defect on a section of a dead electrical line is carried out by measuring a reflection signal characterising the defect and coming from a voltage signal applied to the section. An application of the voltage signal and corresponding measures of reflection signals are simulated with a model of the section for a defect located in different areas along the section. The simulated reflection signals are compared with the measured reflection signal. A site of the defect is localised according to the area of the defect for the simulated reflection signal having a higher correlation with the second reflection signal measured.

No. Publication WIPO : WO2012012897
Non-contact measuring method and apparatus for producing a signal representative of a distance between facing surfaces.: A non-contact measuring method and apparatus for producing a signal (34) representative of a distance (e) between facing surfaces of a first (3) and second parts (5), which are closely spaced apart such as the rotor and stator of an electric rotating machine. The method resides in positioning a sensor (7) on the surface of the first part (3). The sensor (7) includes first (9) and second (11) parallel, superimposed conductive plates electrically insulated from one another. The second plate (11) is located in between the first plate (9) and the surface of the first part (3). The first plate (9) is fed with a high frequency signal through a resistance (19). A high impedance, low input capacity, unitary gain voltage amplifier (27) is fed with the high frequency signal through the resistance (19). The second plate (11) is fed with an output signal (31) of the amplifier (27). The output signal (31) of the amplifier (27) is directly proportional to the distance (e) between the two surfaces (3, 5). The sensor (7) acts as a capacitance in a low pass RC-filtercircuit where R is the resistance (19). The sensor (7) may be adapted to determine discharges in the stator when mounted the roter.

No. Application, patent (CA) : CA 2429164
No. Application, patent (USA) : 6,552,667