Using Phasor Or Vector Analysis Patents (Class 324/650)
  • Patent number: 12163986
    Abstract: A system may include amplifier circuitry configured to drive an electromagnetic load with a driving signal and a processing system communicatively coupled to the electromagnetic load and configured to compensate for current-sensing error of the processing system caused by feedback circuitry of the amplifier circuitry.
    Type: Grant
    Filed: June 22, 2022
    Date of Patent: December 10, 2024
    Assignee: Cirrus Logic Inc.
    Inventors: Anand Ilango, Siddharth Maru, Tejasvi Das, John L. Melanson
  • Patent number: 12019106
    Abstract: This disclosure relates to systems and methods for measuring impedance characteristics of a cryogenic device under test (DUT). A channel select circuit can be configured in a first state to electrically isolate a channel output circuit from the cryogenic DUT and in a second state to electrically couple the channel output circuit to the cryogenic DUT, and at least one resistor can be positioned along a transmission path that couples a pattern generator circuit to a channel output circuit that includes the channel select circuit. A controller can be configured to cause respective test current signals to be provided along the transmission path when the channel select circuit is in respective first and second states to establish respective first and second voltages across the at least one resistor, determine first and second impedance characteristics of the transmission path for determining an impedance of the cryogenic DUT.
    Type: Grant
    Filed: June 2, 2022
    Date of Patent: June 25, 2024
    Assignee: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: Scott F. Allwine, Sunny Bagga, Brian J. Cadwell, Shaun Mark Goodwin
  • Patent number: 11969261
    Abstract: A method of modifying contact status of one or more electrodes in a plurality of electrodes located on a medical device includes measuring an electrical characteristic of each electrode in the plurality of electrodes located on the medical device, determining a contact status for each electrode in the plurality of electrodes based on the measured electrical characteristic for the corresponding electrode, wherein the contact status is indicative of contact with adjacent tissue. The method further includes modifying the contact status of a first electrode in the plurality of electrodes based on the determined contact status of one or more other electrodes in the plurality of electrodes.
    Type: Grant
    Filed: January 12, 2023
    Date of Patent: April 30, 2024
    Assignee: St. Jude Medical, Cardiology Division, Inc.
    Inventors: Eric J. Voth, Jeffrey A. Schweitzer
  • Patent number: 11903737
    Abstract: A method of modifying contact status of one or more electrodes in a plurality of electrodes located on a medical device includes measuring an electrical characteristic of each electrode in the plurality of electrodes located on the medical device, determining a contact status for each electrode in the plurality of electrodes based on the measured electrical characteristic for the corresponding electrode, wherein the contact status is indicative of contact with adjacent tissue. The method further includes modifying the contact status of a first electrode in the plurality of electrodes based on the determined contact status of one or more other electrodes in the plurality of electrodes.
    Type: Grant
    Filed: January 12, 2023
    Date of Patent: February 20, 2024
    Assignee: St. Jude Medical, Cardiology Division, Inc.
    Inventors: Eric J. Voth, Jeffrey A. Schweitzer
  • Patent number: 11790508
    Abstract: Systems and methods for target inspection are provided. The system includes a camera, at least one sensor, and a controller. The camera acquires images of a target over time and the sensor(s) acquire motion data characterizing camera and target movement. The controller generates, using a first computer vision (CV) algorithm, an initial prediction and confidence level regarding an object of interest for a first image acquired at a first time. The controller also determines, using the motion data, a motion parameter characterizing relative motion between the camera and the target at the first time. The controller additionally receives a weighting based upon a second image acquired at a second time prior to the first time. The controller generates, using a second CV algorithm, a final prediction and confidence level for the first image based upon the first image, the initial prediction and confidence level, the motion parameter, and the weighting.
    Type: Grant
    Filed: April 21, 2021
    Date of Patent: October 17, 2023
    Assignee: Baker Hughes Holdings LLC
    Inventors: Sheldon McCrackin, Jeremy Vandam
  • Patent number: 11467102
    Abstract: Various examples related to microwave dielectric analyzers and their use are provided. In one example, a microwave dielectric analyzer includes a measurement apparatus having a conductive electrode that can couple to a microwave analyzer and processing circuitry that can determine a dielectric characteristic of the dielectric specimen using a reflection coefficient measured by the microwave analyzer. The dielectric characteristic can be determined using a computational electromagnetic model of the measurement apparatus. The reflection coefficient can be measured by the microwave analyzer with the dielectric specimen in contact with the conductive electrode and/or sandwiched between conductive electrodes. The conductive electrodes can be axially aligned, and the second electrode may not be coupled to the microwave analyzer.
    Type: Grant
    Filed: July 18, 2019
    Date of Patent: October 11, 2022
    Assignee: COMPASS TECHNOLOGY GROUP LLC
    Inventor: John Weber Schultz
  • Patent number: 10495594
    Abstract: A controller outputs control signals controlling a frequency source to selectively apply different nonzero frequencies of alternating current at different times to an electric sensor within a microfluidic channel.
    Type: Grant
    Filed: January 30, 2015
    Date of Patent: December 3, 2019
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Sirena C. Lu, Melinda M. Valencia, Jeremy Sells, Manish Giri
  • Patent number: 10132853
    Abstract: The embodiments herein are directed to monitoring in real time, power system data so as to provide insights into global operation of a power grid. Such a scheme disclosed herein utilizes rules, which are created by analyzing PMU measurement data, in order to detect the fault location (bus and line) and fault type. Three common types of faults in a power grid, single-line-to-ground (SLG), line-to-line (LL), and three phase faults, can be detected using the methods herein.
    Type: Grant
    Filed: April 11, 2016
    Date of Patent: November 20, 2018
    Assignee: WASHINGTON STATE UNIVERSITY
    Inventors: Xiaodong Liang, Scott Andrew Wallace, Xinghui Zhao
  • Patent number: 10111624
    Abstract: The disclosure provides a circuit for impedance measurement. The circuit includes an excitation source coupled between a first set of input switches. An impedance network is coupled between the first set of input switches and a first set of output switches. The impedance network includes a body impedance and a plurality of electrode impedances. A sense circuit is coupled to the first set of output switches. The sense circuit measures the body impedance and at least one electrode impedance of the plurality of electrode impedances.
    Type: Grant
    Filed: March 26, 2018
    Date of Patent: October 30, 2018
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Anand Hariraj Udupa, Jagannathan Venkataraman, Hussam Ahmed, Sandeep Kesrimal Oswal
  • Patent number: 9714962
    Abstract: A monitoring device is provided that includes a first line section with a first connection point and a second connection point spaced apart from the first connection point in the direction of the line, and with a control unit and with a first current sensing unit, having a current source. A first switch is inserted into the first connecting line and connects the first current source to the first connection point or disconnects it therefrom. In a first state the first switch is closed and the first current is impressed on the first line section and a first voltage determined by the amplitude of the actual current, and in a second state the first switch is open and a second voltage is determined, and the control unit is configured to ascertain the amplitude of the first actual current from the two voltages.
    Type: Grant
    Filed: October 8, 2014
    Date of Patent: July 25, 2017
    Assignee: TDK-Micronas GmbH
    Inventor: Stefan Antonius Albrecht
  • Patent number: 9575139
    Abstract: A novel method for real-time small-signal stability analysis for power electronic-based components in a power system. The method may be used to monitor a power system in real-time by perturbing the source side of an electronic-based component of the power system by injecting a current of about 0.5 to 1 percent of a nominal current of the power system at the source side, while simultaneously perturbing the load side of the power electronic-based component by varying the voltage at the load side. Time-domain results of the simultaneous perturbations may be transferred to frequency-domain results and the stability of the power system may be monitored by obtaining a Nyquist contour and employing Generalized Nyquist Criterion or unit circle criterion.
    Type: Grant
    Filed: April 18, 2016
    Date of Patent: February 21, 2017
    Assignee: The Florida State University Research Foundation, Inc.
    Inventors: Mohamadamin Salmani, Chris S. Edrington
  • Patent number: 9271676
    Abstract: The invention relates to a method for measuring tissue edema. By a method in accordance with the invention an electromagnetic probe (24) is placed on the skin, and the capacitance of the probe is proportional to the dielectric constant of the skin and subcutaneous fat, which is proportional to the water content of the skin. The edema is scored by measuring the capacitance of the electromagnetic probe, so called open-ended coaxial cable, at a high frequency, approximately 20-500 MHz.
    Type: Grant
    Filed: September 23, 2003
    Date of Patent: March 1, 2016
    Assignee: Delfin Technologies Ltd.
    Inventors: Esko Alanen, Aulis Tapani Lahtinen, Jouni Nuutinen
  • Patent number: 9243884
    Abstract: An inductive detection type rotary encoder comprises: a stator; and a rotor that is engaged with a rotation shaft to rotate along with the rotation shaft and faces the stator in an axial direction. The stator comprises at least two transmission windings and reception windings that are disposed from an inner peripheral side to an outer peripheral side, and the rotor comprises at least two magnetic flux coupling bodies that are respectively magnetic flux coupled with these at least two transmission windings and reception windings to configure angle detection tracks. Furthermore, inner peripheral side reception windings and outer peripheral side reception windings are connected in series, and are led out by lead-out wirings commonly used in the inner peripheral side reception windings and the outer peripheral side reception windings.
    Type: Grant
    Filed: January 17, 2014
    Date of Patent: January 26, 2016
    Assignee: MITUTOYO CORPORATION
    Inventor: Kouji Sasaki
  • Patent number: 9119623
    Abstract: An electrosurgical generator apparatus controls a variable output signal to electrodes. The generator apparatus operates in a cut mode, a coagulation mode or a stimulate mode. The generator apparatus comprises a DC power supply that provides regulated low voltage and high voltage outputs and a radio frequency (RF) waveform generator circuit that provides pulse duration modulation (PDM) of a carrier signal. The carrier signal directly affects the variable output signal to the electrodes. A control circuit controls a variable output signal to electrodes used in electrosurgical procedures. The control circuit comprises a DC power supply circuit that provides regulated low voltage and high voltage outputs and an RF waveform generator circuit that provides pulse duration modulation of a carrier signal. The carrier signal directly affects the variable output signal to the electrodes.
    Type: Grant
    Filed: November 29, 2010
    Date of Patent: September 1, 2015
    Assignee: Synergetics USA, Inc.
    Inventors: Jerry L. Malis, Leonard I. Malis, Robert R. Acorcey, David L. Solt, Anthony John Groch
  • Patent number: 9000778
    Abstract: A method for underground pipeline monitoring in which a continuous alternating electrical current having a current frequency in a range of about 1 kHZ to about 8 kHz is imparted onto a pipeline, producing an alternating magnetic field at the current frequency along the pipeline. Distributed along the pipeline is a network of RFID tag sensors which absorb an amount of energy from the alternating magnetic field. The impedance of the sensors is modulated, producing a modulated sensor impedance which is detected at a location proximate the location at which the continuous alternating electrical current is imparted onto the pipeline.
    Type: Grant
    Filed: August 15, 2011
    Date of Patent: April 7, 2015
    Assignee: Gas Technology Institute
    Inventors: Christopher John Ziolkowski, James Emerson Huebler, Michael Christian Mensinger, Jr.
  • Patent number: 8947113
    Abstract: A test system for characterizing an antenna tuning element is provided. The test system may include a test host, a radio-frequency tester, and a test fixture. The test system may calibrate the radio-frequency tester using known coaxial standards. The test system may then calibrate transmission line effects associated with the test fixture using a THRU-REFLECT-LINE calibration algorithm. The antenna tuning element may be mounted on a test socket that is part of the test fixture. While the antenna tuning element is mounted on the test socket, scattering parameter measurements may be obtained using the radio-frequency tester. An equivalent circuit model for the test socket can be obtained based on the measured scattering parameters and known characteristics of the antenna tuning element. Once the test socket has been characterized, an equivalent circuit model for the antenna tuning element can be obtained by extracting suitable modeling parameters from the measured scattering parameters.
    Type: Grant
    Filed: May 7, 2012
    Date of Patent: February 3, 2015
    Assignee: Apple Inc.
    Inventors: Liang Han, Jayesh Nath, Matthew A. Mow, Peter Bevelacqua, Joshua G. Nickel, Mattia Pascolini, Robert W. Schlub, Ruben Caballero
  • Publication number: 20140306720
    Abstract: Measurements, e.g. S-parameter measurements may be performed by obtaining a complex ratio of at least two signals, using a single signal-receiver while eliminating noise problems traditionally associated with single receiver systems. A Vector Signal Generator (VSG) may be used to generate the input stimulus (signal), making it possible to share the local oscillator (LO) signal of the VSG with a single vector receiver, such that the phase noise of the LO signal is common to both the VSG and the vector receiver. When the stimulus signal from the VSG is observed with the vector receiver, the LO phase noise is unobservable, resulting in a significant reduction of the phase noise in the measured signals in both the numerator and the denominator, which in turn leads to a significant reduction in the phase noise of the ratio while retaining the benefits of a simple, single receiver.
    Type: Application
    Filed: April 15, 2013
    Publication date: October 16, 2014
    Applicant: National Instruments Corporation
    Inventors: Daniel S. Wertz, Michael J. Seibel
  • Patent number: 8823392
    Abstract: A system and method for controlling an impedance tuner system. In one embodiment, a web-enabled electronic controller controls an impedance tuner system including a signal transmission line and an electronically-controllable impedance-varying system coupled to the signal transmission line for affecting the impedance presented by the signal transmission line. The controller has a communication port, and an electronic processor configured to process external command signals and generate electronic control signals to configure the impedance-varying system in response to the command signals. An electronic memory stores sets of data and one or more web pages. The controller has a communication server and is configured to receive or send signals through a communication channel from or to a client computer system. The communication server is configured to be responsive to a request message from a client computer system to send a response comprising a web page to the client computer system.
    Type: Grant
    Filed: April 6, 2011
    Date of Patent: September 2, 2014
    Assignee: Maury Microwave, Inc.
    Inventor: Roman Meierer
  • Patent number: 8810257
    Abstract: Signal measuring systems, and measurement methods are disclosed.
    Type: Grant
    Filed: November 8, 2011
    Date of Patent: August 19, 2014
    Assignee: Maury Microwave, Inc.
    Inventor: Gary R. Simpson
  • Patent number: 8786293
    Abstract: A wideband four noise parameter measurement system and method uses electro-mechanical wideband tuners and fast noise and small signal receivers (network analyzers) to collect noise data in fast frequency sweeps over a large number of randomly distributed source tuner states; because of the random nature of source impedances, additional monitoring equipment allow evaluating critical device parameters in view of output mismatch and instabilities in order to validate the measured data. Multiple noise parameter extractions for all possible cross-combinations of source impedance states at each measured frequency allows reliable and physically meaningful generation of wideband noise parameters, even for very low noise and potentially unstable DUT's.
    Type: Grant
    Filed: August 5, 2011
    Date of Patent: July 22, 2014
    Inventor: Christos Tsironis
  • Patent number: 8736281
    Abstract: A sensing system comprises a material having a matrix structure in which a plurality of sensing elements are embedded, the sensing elements having electron distribution and/or transport properties that change in response to a change in a physical or chemical property of the material. The sensing system further comprises a receiver, including an antenna, the receiver arranged to receive a source RF signal and a returned RF signal, the returned RF signal being received from the material. A change in the electron distribution and/or transport properties of the sensing elements cause the source RF signal to change, such that a change in a property of the material can be determined from the returned RF signal. A corresponding method of sensing a change in a property of a material is also provided.
    Type: Grant
    Filed: November 28, 2008
    Date of Patent: May 27, 2014
    Inventors: Christopher R. Lowe, Quentin Tannock, Adrian Stevenson, Karishma Jain
  • Patent number: 8718586
    Abstract: Shockline-based samplers of a vector-network analyzer (VNA) have enhanced dynamic range by using a dynamic bias network applied to the non-linear transmission lines (NLTLs) or shocklines. The bias voltage applied to the NLTL provides direct control over the falling-edge shockline compression, and thus the insertion loss and overall RF bandwidth of the sampler. Alternating between a forward bias voltage to turn off a shockline sampler when it is not needed and thereby reducing spurious generation and improving isolation can be alternatively applied with a reverse bias voltage to turn on the shockline sampler in a normal operation mode. By measuring the shockline output and providing feedback in the reverse-bias mode, the bias voltage can be dynamically adjusted to significantly increase the performance of the NLTL based sampler. In the presence of a strong positive bias voltage, the incoming LO and its harmonics experience large ohmic losses thus preventing gating pulses from forming in the shockline.
    Type: Grant
    Filed: June 30, 2009
    Date of Patent: May 6, 2014
    Assignee: Anritsu Company
    Inventors: Jon Martens, Karam Michael Noujeim
  • Publication number: 20140070820
    Abstract: The present invention relates to electronic power converter suitable, in a first mode, for receiving electrical voltage and/or current magnitudes from a first device as input, for processing them using processing means capable of measuring said electrical magnitudes and servocontrolling said electrical magnitudes based on said measurements and constraints specific to a second device, and for providing the adapted voltage and/or current magnitudes to said second device.
    Type: Application
    Filed: May 15, 2012
    Publication date: March 13, 2014
    Applicants: UNIVERSITY DE FRANCHE-COMTE, CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE (C.N.R.S.)
    Inventors: Daniel Depernet, Oumar Ba, Alain Berthon
  • Publication number: 20130099800
    Abstract: A controller and infrastructure for an impedance analyzer measures responses to perturbations to respective phases of a multi-phase system at an interface between stages thereof (which may be considered as a source and load in regard to each other), such as a multi-phase electrical power system, to determine a transfer function for each phase of the multi-phase system from which the impedance of each of the source and load can be calculated, particularly for assessing the stability of the multi-phase system.
    Type: Application
    Filed: September 14, 2012
    Publication date: April 25, 2013
    Inventors: Gerald FRANCIS, Rolando BURGOS, Dushan BOROYEVICH, Fred WANG, Zhiyu SHEN, Paolo MATTAVELLI, Kamiar KARIMI, Sheau-Wei Johnny FU
  • Patent number: 8417189
    Abstract: A high-frequency VNA system is provided using non-linear transmission line (NLTL or shockline) based samplers configured to provide scalable operation characteristics. Scaling to adjust noise performance vs. frequency is accomplished as follows: (1) increasing or decreasing the fall time of a shockline's output voltage waveform. This is accomplished by changing the number of Schottky varactors in a shockline, as well as changing the shockline's Bragg cutoff frequency by setting the spacing between Schottky varactors; (2) changing the structure of the pulse-forming network connected with the sampler by changing the length of the differentiator arms in the sampler pulse-forming network; and (3) changing the LO signal frequency applied to the shockline. Multiple NLTL based samplers are multiplexed to form a broadband reflectometer with the multiplexing circuitry selectively connecting one of the NLTL based sampler segments at a time to allow user selection of a desired performance vs.
    Type: Grant
    Filed: June 10, 2010
    Date of Patent: April 9, 2013
    Assignee: Anritsu Company
    Inventors: Karam Michael Noujeim, Jon S. Martens
  • Patent number: 8410786
    Abstract: 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 F1 and F2 that are provided through a combiner for characterization of the PIM circuit. To enable distance determination, an FM measurement is created by using a offset sweep generator attached to one of the two frequency sources. To avoid frequencies blocked by the band reject filter, a desired harmonic of a test PIM harmonic signal is selected outside the band of the band reject filter.
    Type: Grant
    Filed: June 8, 2011
    Date of Patent: April 2, 2013
    Assignee: Anritsu Company
    Inventor: Donald Anthony Bradley
  • Patent number: 8378693
    Abstract: A front end of a vector network analyzer (VNA) on an integrated circuit includes a clock generator and two ports. The VNA couples to a device under test (DUT) using the two ports. Each port may include a plurality of receivers and a VSWR bridge, and can be configured as either an input or an output. The clock generator can generate a stimulus signal, an in-phase I clock signal, and a quadrature-phase Q clock signal. The output port provides the stimulus signal to the DUT and measures both reference and reflected power from the DUT, such as by utilizing two receivers by using direct conversion and the I and Q clock signals. The input port measures transmitted power through the DUT using a second VSWR bridge and one of its receivers by using direct conversion along with the I and Q clock signals. The VNA IC can provide S-parameter measurements to a processing unit for further processing and/or analysis to compute the DUT S-parameters.
    Type: Grant
    Filed: October 27, 2008
    Date of Patent: February 19, 2013
    Assignee: National Instruments Corporation
    Inventor: Michel M. Azarian
  • Patent number: 8362789
    Abstract: Embodiments according to the present invention provide an Impedance-based Arc-Fault Determination Device (IADD) and method that, when attached to an electrical node on the power system and through observations on voltage, current and phase shift with a step load change, determine the effective Thevenin equivalent circuit or Norton equivalent circuit at the point of test. The device and method determine the expected bolted fault current at the test location of interest, which enables calculation of incident energy and the assignment of a flash-hazard risk category.
    Type: Grant
    Filed: October 2, 2009
    Date of Patent: January 29, 2013
    Assignees: Clemson University Research Foundation, Duke Energy Carolina, LLC
    Inventors: Edward Randolph Collins, Jr., Timothy Lee Smith, Randall J. Emanuel
  • Patent number: 8278944
    Abstract: A vector network analyzer (VNA) in accordance with the present invention for measuring a frequency response of a device under test (DUT) includes a signal source, a port, a signal path connecting the port and the signal source, and a reflectometer receiver that when activated taps onto the signal path within a primary frequency range. The port is adapted to be electrically connected with the DUT while disconnected from a frequency-extension module or electrically connected to the DUT with the frequency-extension module serially connected between the port and the DUT. When the port is electrically connected with the DUT and electrically disconnected from the frequency-extension module, the reflectometer receiver is active so that the frequency response of the DUT is measureable within the primary frequency range using the reflectometer receiver and the signal source.
    Type: Grant
    Filed: July 30, 2010
    Date of Patent: October 2, 2012
    Assignee: Anritsu Company
    Inventor: Karam Michael Noujeim
  • Patent number: 8203347
    Abstract: A reflection element determination device derives error factors in a first signal source and a second signal source based on measurement results of a signal in respective states in which reflection elements are respectively connected to the first signal source and the second signal source, and measurement results of a signal in a state in which the first signal source and the second signal source are connected with each other via a transmission element, derives transmission characteristics of the transmission element based on the measurement results of a signal in the state in which the first signal source and the second signal source are connected with each other via the transmission element and the derived error factors, and determines whether the reflection elements realize predetermined reflection states based on the derived transmission characteristics of the transmission element and transmission characteristics of the transmission element which have been known before the derivation, where the transmissi
    Type: Grant
    Filed: August 24, 2007
    Date of Patent: June 19, 2012
    Assignee: Advantest Corporation
    Inventors: Yoshikazu Nakayama, Takao Kawahara, Masato Haruta
  • Patent number: 8198904
    Abstract: Voltage instantaneous value time-series estimation data and a present-time voltage estimation value are calculated by using an actually-measured frequency and voltage instantaneous value time-series data according to a least square method. A present-time voltage effective value is determined by using the calculated voltage instantaneous value time-series estimation data, and a present-time synchrophasor, a voltage distortion degree and an inter-bus-line synchrophasor phase angle difference are determined by using the present-time voltage effective value and the present-time voltage estimation value.
    Type: Grant
    Filed: March 30, 2007
    Date of Patent: June 12, 2012
    Assignee: Mitsubishi Electric Corporation
    Inventor: Kempei Seki
  • Patent number: 8138697
    Abstract: A speed estimation method for determining the speed of a sensorless permanent magnet brushless motor having one or more phases driven by one or more stages of an inverter, each stage including high- and low-switches connected in series across a DC Bus and having a respective common switched node, the respective switched node being coupled to a respective motor phase terminal.
    Type: Grant
    Filed: April 18, 2008
    Date of Patent: March 20, 2012
    Assignee: International Rectifier Corporation
    Inventor: Marco Palma
  • Publication number: 20120033473
    Abstract: The present disclosure describes systems and methods for monitoring an electrical power grid using loosely synchronized phasors. The grid can include a phasor measurement unit (PMU) that keeps a highly-accurate time, such as a time provided by GPS signals. A solar power inverter can include a clock that is synchronized to a less-accurate time, such as a time provided by a public time server or a radio time signal. The inverter can also include a PMU that generates phasors timestamped according to the less-accurate time. The inverter can receive phasors from the grid PMU. Although the grid and inverter phasors can be loosely synchronized in time, the inverter can analyze the grid and inverter phasors to determine a state of the grid. For example, the inverter can calculate a Pearson's correlation coefficient based on the grid and inverter phasors, and use the result to determine a state of the grid.
    Type: Application
    Filed: July 12, 2011
    Publication date: February 9, 2012
    Inventor: Mesa P. Scharf
  • Patent number: 8063648
    Abstract: A method and device are provided for demodulation of an output signal from a transducer (1) driven by an alternating excitation signal having an excitation frequency. The transducer produces an amplitude-modulated output signal (y(t)) containing the quantity to be measured. The device has sampling units (5,6,7) to sample the output signal from the transducer and the output signal from the excitation unit, and a computation unit (8) to compute a first complex valued quantity ( Y) including information on the amplitude and phase of the output signal at the excitation frequency based on sampled values of the output signal from the transducer, compute a second complex valued quantity (?, ?) including information on the amplitude and phase of the excitation signal at the excitation frequency based on sampled values of the excitation signal, forming a complex valued output quotient between the first and second complex valued quantities, and compute the demodulated output signal (Od) based on the output quotient.
    Type: Grant
    Filed: May 10, 2007
    Date of Patent: November 22, 2011
    Assignee: ABB AB
    Inventors: Jan Nilsson, Jarl R. Sobel
  • Patent number: 8044670
    Abstract: An apparatus for determining a resonant frequency of a wind turbine tower is provided. The apparatus includes a processing unit configured to receive an acceleration measurement value, the acceleration measurement value representative of the acceleration of the wind turbine tower in the direction parallel to a rotor rotational axis of the wind turbine and/or in the direction perpendicular to both the rotor rotational axis and the tower axis of the wind turbine. The apparatus includes a memory configured to store a series of acceleration measurement values, and the processing unit includes a Fourier transform module configured to calculate a spectral vector based on calculating a convolution-based fast Fourier transform of the series of acceleration measurement values, and includes a resonant frequency calculation module configured to calculate the tower resonant frequency based on the calculated spectral vector.
    Type: Grant
    Filed: March 12, 2009
    Date of Patent: October 25, 2011
    Assignee: Siemens Aktiengesellschaft
    Inventors: Martin Bjerge, Per Egedal
  • Patent number: 8022687
    Abstract: The invention relates to a method for measuring objects for measurement, by means of a network analyzer with several measurement ports, at least one signal generator, for stimulating the object for measurement and at least one local oscillator, for measurement of the signal transmitted or reflected from the object for measurement by the superposition principle. According to the invention, on a frequency change, only the frequency of the local oscillator or the frequency of the signal generator is changed but not the frequency of the local oscillator and the signal generator simultaneously.
    Type: Grant
    Filed: January 5, 2007
    Date of Patent: September 20, 2011
    Assignee: Rohde & Schwarz GmbH & Co. KG
    Inventor: Georg Ortler
  • Patent number: 7924024
    Abstract: A calibration module, for use in calibrating a VNA, includes ports connectable to the VNA, calibration standards, and single pole multi throw (SPMT) switches. Each SPMT includes a single pole terminal, multiple throw terminals and a shunt terminal corresponding to each multiple throw terminal. A switching path is between each throw terminal and the single pole terminal, and between each shunt terminal and the single pole terminal. Each switching path includes at least one solid state switching element. The calibration standards are selectively connectable to the ports of the calibration module by selectively controlling the switching elements. Each port of the calibration module is directly connected to a throw terminal of one of the SPMT switches. Also, unique algorithm are provided for calibrating a VNA when using a calibration impedance that is a hybrid of a reflect standard and a transmission standard, which can be achieved using the calibration module.
    Type: Grant
    Filed: February 1, 2008
    Date of Patent: April 12, 2011
    Assignee: Anritsu Company
    Inventors: Jon S. Martens, Alexander Feldman
  • Patent number: 7816927
    Abstract: A method of identifying voltage instability in a power system via identification of a weakest line and bus that contribute to the collapse of the system is provided. The method includes periodically calculating an extended line stability index for the transmission lines monitored in the power system; and using the extended line stability index to determine the distance of an operation state in the power system from a collapse point of the system caused by voltage instability.
    Type: Grant
    Filed: September 25, 2007
    Date of Patent: October 19, 2010
    Assignee: British Columbia Hydro and Power Authority
    Inventors: Wenyuan Li, Paul Choudhury, Jun Sun, Juan Yu, Yang Wang
  • Patent number: 7768271
    Abstract: Method for calibrating a vectorial network analyzer, with n measurement ports (n>2) and at least m measurement sites, where m>n+1 includes measurement of three different n-port reflection standards, connected between measurement ports in any desired order, and successive measurement of reflection and transmission parameters at different transmission standards, connected between two respective measurement ports, and computational determination of error coefficients and error-corrected scattering matrices [Sx] of the n-port standards. Reflection standards, Short and Open, are unknown, but physically identical at each n-fold one-port. Reflection standard, realized by wave terminations, is known, but can be different at each n-fold one-port. Transmission standards are measured at a transmission standard, having known length and attenuation at a two-port, and at unknown transmission standards, identical for incident and reflected waves at remaining two-ports, which can be connected.
    Type: Grant
    Filed: November 19, 2007
    Date of Patent: August 3, 2010
    Assignee: SUSS Microtec Test Systems GmbH
    Inventors: Andrej Rumiantsev, Steffen Schott, Stojan Kanev
  • Patent number: 7714592
    Abstract: A system and method of detecting changes in the impedance of a segment of medium voltage power line is provided. In one embodiment, the method comprises receiving voltage data comprising data of the voltage of the power lines at locations at a plurality of different points in time, receiving current data that comprises data of the current flowing between adjacent locations at the plurality of points in time, intermittently determining an impedance of the power lines between adjacent locations based on the voltage data and current data, monitoring the impedance of the power lines between adjacent locations over time, and providing a notification of a change in the impedance of a power line between adjacent locations upon detection of a change in the impedance beyond a threshold change.
    Type: Grant
    Filed: November 7, 2007
    Date of Patent: May 11, 2010
    Assignee: Current Technologies, LLC
    Inventors: William O. Radtke, David G. Kreiss
  • Patent number: 7683633
    Abstract: A system for measuring a frequency response of an electrical network includes a signal source, a signal source path, a reflectometer receiver interactively associated with the signal source path by a directional coupler, and one or more additional reflectometer receivers arranged in series along the signal source path and associated with the signal source path by one or more respective additional directional couplers. The directional coupler and one or more respective additional directional couplers operate at different frequency ranges.
    Type: Grant
    Filed: September 11, 2007
    Date of Patent: March 23, 2010
    Assignee: Anritsu Company
    Inventor: Karam Michael Noujeim
  • Patent number: 7646205
    Abstract: The invention provides for a method of using a network analyzer and a test controller for measuring S-parameters of a device, which can assume a plurality of states, and which can switch very fast from one state to another. The test controller sends a trigger to the analyzer, which starts a frequency sweep when it receives this trigger. The frequency sweep, having substantially the same start and stop frequency, is provided to the device. The analyzer then executes a measurement of at least one S-parameter of the device, stores the S-parameter data from the measurement and provides the test controller with a trigger. The test controller then updates the device to the next state in a predetermined sequence of states when it receives the trigger from the analyzer. These steps are repeated until all states in the predetermined sequence of states have been measured.
    Type: Grant
    Filed: December 7, 2004
    Date of Patent: January 12, 2010
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventor: Lennart Berlin
  • Publication number: 20090309612
    Abstract: A method and a system for determining a circular characteristic for distance protection of a three-phase electric line, the system comprising means for detecting a fault on the electric line, means for identifying a faulted phase or phases of the electric line, means for determining, at a measuring point, a first fault loop impedance by using voltage(s) of the faulted phase(s), a second fault loop impedance by using a polarization voltage and a third fault loop impedance by using predetermined line parameters, and means for determining a radius and midpoint of the circular characteristic.
    Type: Application
    Filed: September 19, 2006
    Publication date: December 17, 2009
    Applicant: ABB Technology AG
    Inventors: Ari Wahlroos, Janne Altonen
  • Patent number: 7629795
    Abstract: A vector impedance measurement system (100) includes a first radio frequency (RF) source (101) for providing energy to a test circuit. A measurement device (111) is used for providing a first network measurement based upon the voltage and current at the terminals of the test circuit. A second RF source (103) is used for down converting the first network measurement to a second network measurement that is lower in frequency. The vector impedance system (100) operates to calculate a complex impedance using both the magnitude and phase angle of the second network measurement as determined by a processor (133). In that the lower frequency at which signal processing is performed is a fixed frequency, many sensitive parameters of the band pass filters, such as gain and phase shift, can be easily calibrated and do not change during operation, resulting in a simpler calibration process and very accurate data measurements.
    Type: Grant
    Filed: July 30, 2007
    Date of Patent: December 8, 2009
    Inventor: Robert H. Clunn
  • Patent number: 7592818
    Abstract: A measuring method and measurement system that includes a signal source that applies a signal to a device under test, a scalar measuring instrument that measures a reflected wave reflected from the device under test or a transmitted wave transmitted through the device under test as a scalar value, and a superimposing signal system that superimposes three different vector signals whose relation values are specified in advance on the reflected wave or the transmitted wave of the device under test. The three vector signals are superimposed on the reflected wave or the transmitted wave of the device under test, and the superimposed signals are each measured as a scalar value by the electric-power measuring instrument. The three measured scalar values are converted into a single vector value using the specified relation values of the three vector signals, thereby obtaining a transmission coefficient of the device under test.
    Type: Grant
    Filed: February 29, 2008
    Date of Patent: September 22, 2009
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Taishi Mori, Gaku Kamitani
  • Publication number: 20090167323
    Abstract: A system composed of an RF input, a receiver system and, connected in series between the RF input and the receiver, an amplifier, a gate switch and a bandpass filter. The receiver system is operable to determine the characteristic of the DUT based on an RF input signal received from the DUT. The amplifier receives and amplifies the RF input signal to generate an amplified signal at a power level that exceeds the maximum input power of the receiver system. The bandpass filter is configured to select from the gated signal a selected signal comprising a wanted frequency component. The band-pass filter has a rise-time in relation to the ON time of the gate switch such that the selected signal has a maximum power that does not exceed the maximum input power of the receiver system. In another embodiment, the system additionally comprises a mixer interposed between the RF input and the amplifier.
    Type: Application
    Filed: December 31, 2007
    Publication date: July 2, 2009
    Inventor: Robert E. Shoulders
  • Patent number: 7545151
    Abstract: Provided herein are techniques for characterizing a test fixture that is used for connecting a device under test (DUT) to a vector network analyzer (VNA), e.g., to thereby enable de-embedding of the test fixture from measurements of the DUT connected to the test fixture. In an embodiment, the test fixture is separated into 4-port test fixture segments, based on which ports of the DUT have internal coupling. Each test fixture segment has an outer 2-port reference plane and an inner 2-port reference plane. A 4-port calibration is performed at outer planes of the two test fixture segments, while corresponding ports of the inner planes of the test fixture segments are connected together with thru segments, to thereby determine a thru set of S-parameters. A set of S-parameters is determined for each of the 4-port test fixture segments, based on the thru set of S-parameters.
    Type: Grant
    Filed: April 20, 2007
    Date of Patent: June 9, 2009
    Assignee: Anritsu Company
    Inventors: Jon S. Martens, David V. Judge
  • Patent number: 7532991
    Abstract: In a magnetic data processing device, an input part sequentially inputs magnetic data outputted from a two-dimensional or three-dimensional magnetic sensor. The magnetic data is two-dimensional or three-dimensional vector data that is a linear combination of a set of fundamental vectors. The magnetic data processing device stores a plurality of the inputted magnetic data as a data set of statistical population in order to update an old offset of the magnetic data with a new offset. An offset derivation part derives the new offset based on the old offset and the data set of statistical population under a constraint condition that the new offset be obtained as the sum of the old offset and a correction vector.
    Type: Grant
    Filed: March 6, 2007
    Date of Patent: May 12, 2009
    Assignee: Yamaha Corporation
    Inventor: Ibuki Handa
  • Patent number: 7518353
    Abstract: A vector network analysis system and a method of measuring use offset stimulus signals to stimulate a balanced device under test (DUT) to determine performance parameters. The system includes an offset stimulus source that provides a plurality of stimulus signals and a vector network analyzer. At least one stimulus signal is offset from another stimulus signal of the plurality in one or both of frequency and time-varying phase. The offset stimulus source includes a first signal source and a second signal source that respectively provides the offset stimulus signals. The method of measuring includes generating the offset stimulus signals and applying the offset stimulus signals to a balanced port of the DUT to stimulate the DUT. The performance parameters are determined from measurements of the offset stimulus signals and one or more response signals from the stimulated DUT.
    Type: Grant
    Filed: April 7, 2006
    Date of Patent: April 14, 2009
    Assignee: Agilent Technologies, Inc.
    Inventors: Hassan Tanbakuchi, Wing J. Mar
  • Patent number: RE44582
    Abstract: In a magnetic data processing device, an input part sequentially inputs magnetic data outputted from a two-dimensional or three-dimensional magnetic sensor. The magnetic data is two-dimensional or three-dimensional vector data that is a linear combination of a set of fundamental vectors. The magnetic data processing device stores a plurality of the inputted magnetic data as a data set of statistical population in order to update an old offset of the magnetic data with a new offset. An offset derivation part derives the new offset based on the old offset and the data set of statistical population under a constraint condition that the new offset be obtained as the sum of the old offset and a correction vector.
    Type: Grant
    Filed: May 11, 2011
    Date of Patent: November 5, 2013
    Assignee: Yamaha Corporation
    Inventor: Ibuki Handa