| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 324520000 | By frequency sensitive or responsive detection | 11 |
| 20090079436 | METHOD AND APPARATUS FOR GENERALIZED AC AND DC ARC FAULT DETECTION AND PROTECTION - According to the features discussed herein, through a single generalized arc-fault detection algorithm, various types of series and/or parallel arc faults can be detected without any nuisance trip for either AC or DC Electric Power Systems. Running Discrete Fourier Series (RDFS) formulation for nuisance-free operation and cost-effective implementation is developed. Unlike other methods which require numerous source and load-side current and voltage measurements, only source side current is required. An arc detector may include a first detector to monitor variations of a magnitude of a fundamental component of a current, and a second detector to monitor an overload condition based in an i | 03-26-2009 |
| 20090256576 | APPARATUS AND METHOD FOR GROUND FAULT DETECTION AND LOCATION IN ELECTRICAL SYSTEMS - The present invention is implemented by deploying an enhanced ground fault detection and location apparatus and by using the apparatus in conjunction with specific circuit analysis methods, using the information generated by the ground fault detection and location apparatus. The ground fault detection and location apparatus comprises the functionality of a voltmeter, an ammeter, a phase angle meter, a frequency generator, and a variable power supply, thereby providing for a variety of signals and analyses to be performed on a unintentionally grounded circuit in an ungrounded AC or DC power distribution system. The ground fault detection and location apparatus is capable of operating in six different modes, with each mode providing a different capability or opportunity for detecting, analyzing, and locating one or more unintentionally grounded circuits in an normally ungrounded AC or DC power distribution system. Additionally, the present invention is configured to manipulate a ground fault current at a first target frequency and a second target frequency, thereby enabling more rapid and efficient location of ground faults. | 10-15-2009 |
| 20100073008 | Partial Discharge Coupler for Application on High Voltage Generator Bus Works - A partial discharge coupler for detecting partial discharges in a conductor includes a frequency dependent network, a differential amplifier and a frequency selective coupling component. The frequency dependent network includes a first filter component, a fuse component and a load component, typically coupled together in series with reference to a first ground. The first filter component filters the high voltage, low frequency alternating current signal carried by the conductor from the load component and passes high frequency partial discharge pulse signals to the load component. The frequency selective coupling component couples in series between the differential amplifier and the load component. The output of the differential amplifier is configured to provide an output that is isolated from the ground connection for communicating detected partial discharge signals to partial discharge test equipment. | 03-25-2010 |
| 20100085061 | CALIBRATED TWO PORT PASSIVE INTERMODULATION (PIM) DISTANCE TO FAULT ANALYZER - A PIM measurement circuit enables making forward and reverse PIM measurements on any 1 port (reflection) or 2 port (transmission) device with the ability to determine in distance where individual PIM impairments are located as well as their magnitude. The PIM measurement circuit includes two frequency sources that are provided through a combiner for a CW characterization of the PIM circuit. To enable distance determination, an FM measurement is created by using a saw tooth offset sweep generator attached to one of the two frequency sources. With downconversion and processing of signals from the PIM impairments, the FM signal provides a frequency variation that is converted using a Fourier transform or spectrum analysis for separation of frequencies, enabling determination of the distance of the PIM sources as well as their magnitudes. | 04-08-2010 |
| 20100164504 | PASSIVE INTERMODULATION (PIM) DISTANCE TO FAULT ANALYZER WITH SELECTABLE HARMONIC LEVEL - A distance to PIM measurement circuit is made using a device such as an AWS transceiver that has separate transmit and receive bands. With a typical AWS transceiver placed in close proximity to a PCS transceiver, the AWS device will include a band reject filter to eliminate interference from the PCS signals. The PIM measurement circuit includes two frequency sources F | 07-01-2010 |
| 20140002097 | PASSIVE INTERMODULATION MEASUREMENT APPARATUS | 01-02-2014 |
| 20140139233 | APPARATUS FOR INSPECTING PASSIVE COMPONENT HAVING SIGNAL TRANSMISSION LINE - An apparatus for inspecting a passive component having a signal transmission line on a printed circuit board (PCB), includes a reflectometry unit for inputting an incident signal to an input port connected to the signal transmission line, receiving a reflected signal in response to the incident signal, and computing a plurality of frequency-based reflection coefficient values in a preset frequency range and a plurality of time-based reflection coefficient values in a preset time range based on the incident signal and the reflected signal; and a defect detection unit for determining whether the signal transmission line has a defect based on the plurality of frequency-based reflection coefficient values, and determining a location of the defect on the signal transmission line based on the plurality of time-based reflection coefficient values. | 05-22-2014 |
| 20140354293 | FAULT DETECTION SYSTEM - A system for the early detection of faults in a low voltage distribution network in which at least two detectors are each located on one of two power poles at either end of a section of a power distribution line, each detector includes a GPS unit, an uninterruptable power supply, a communication means to send data to a base station, antenna sensors having a bandwidth of 1 MHz to 3 GHz for each wire in the power line, a processor to receive signals from each sensor and collect data relating to the maximum value, time of maximum value, minimum value and time of minimum value for partial discharge signals within the range and the processor or base station being programmed to analyse the collected data to identify location of pulses above a predetermined value and record the number of such pulses at each location over a predetermined time interval to enable identification of likely sites of faults in the distribution line. | 12-04-2014 |
| 20150346267 | PARTIAL DISCHARGE SENSOR EVALUATION METHOD AND PARTIAL DISCHARGE SENSOR EVALUATION APPARATUS - A partial discharge sensor evaluation method includes a first frequency characteristic measuring process in which, in a state where a reference antenna | 12-03-2015 |
| 20160154050 | CABLE SYSTEM PROBLEM DETECTION VIA CHARACTERISTIC FREQUENCY | 06-02-2016 |
| 20160202309 | APPARATUS AND METHOD FOR DETECTING CABLE FAULT | 07-14-2016 |
