Texas Instruments Corporation

Sensata Technologies, Inc.

Other

Sensata Technologies Massachusetts, Inc.

Keith W Kawate

Thomas Richard Maher

Peter G Berg

Christian V Pellon

Michael J Lavado

Eric P Reidemeister

Larry K Johnson

Sepideh H Nott

David L Corkum

Stephen B Offiler

Norman E LeComte

Roger D Mayer

Anthony J Sabetti

Jianhong Kang

James P Berthold

Lynwald Edmunds

Lucien Paul Fontaine

William H Giolma

Michael T Parker

Steven Beringhause

Robert O Southworth

Stephen P Sacarisen

Douglas B Strott

Edward M Gonsalves

Thomas J Charboneau

Keith Richard Washburn

Mark David Rabiner

Christopher A Nicolls

Keith A Singer

William Bentley

Jeffrey B Ting

Gene E Blankenship

Eric Morrison

Robert Zanelli

Thomas Gasper

Joseph L Medeiros

Lee Martin

Chistian Pellon

Damir A Spanjol

Eric Visser

Robert P Bishop

Gerhard Andrew Foelsche

Carleton M Cobb, Iii

Stanley J Lukasiewicz

Eric K Larson

Raymond E Mandeville

John A Haug

June Park

John J Chrupcala

John A Powning

Gerald H Fleischfresser

Mark Genovese

Robert M Margolis

Thomas Wiecek

Timothy White

Douglas B Christensen

Lidu Huang

Richard W Strachan, Deceased

Lucien Fontaine

Thomas R Maher

Michael Parker

Systems and methods of detecting arcing in a DC power system that can provide improved noise propagation immunity. The system includes at least two current sensors for monitoring at least two current outputs, respectively. The current sensors have reverse polarities, and are configured and arranged in parallel to provide a combined current output signal. The current sensors monitor the respective current outputs, which are provided for monitoring by the current sensors over at least two adjacent conductors. If arcing occurs at a location on a first conductor, then arcing (adjacent conductor crosstalk), having an arc current signature like that of the arcing on the first conductor, can occur at a location on the other adjacent conductor. The system can effectively cancel out such adjacent conductor crosstalk within a photovoltaic (PV) system, thereby improving the capability of an arc fault detection device for detecting arcing at the PV string level.

Noise propagation immunity of a multi-string arc fault detection device

Systems and methods of detecting arcing in DC power systems that can differentiate between DC arcs and load-switching noise. The systems and methods can determine, within a plurality of predetermined time intervals, at least the pulse count (PC) per predetermined time interval, and the pulse duration (PD) per predetermined time interval, in which the PC and the PD can correspond to the number and the intensity of potential arcing events in a DC power system, respectively. The systems and methods can process the PC and PD using one or more arc fault detection algorithms, thereby differentiating between DC arcs and load-switching noise with increased reliability.

Home run arc detection at the photovoltaic string level using multiple current sensors

Systems and methods of discriminating DC arcs and load switching noise

A circuit interruption device includes at least one constriction zone. The constriction zone provides for interference with arcing of an electrical signal. The device may include at least one expansion zone. The device may include at least one movable component to assist in creation of the at least one constriction zone. A method of fabrication is provided.

Circuit interruption device with constrictive arc extinguishing feature

In an embodiment, an apparatus may include a sense element that may measure a property such as, for example, pressure. The sense element may produce an output based on the measured property. Circuitry associated with the sense element may store a voltage that represents the output produced by the sense element. The circuitry may include, for example, a capacitor which may store the voltage. The stored voltage may include one or more parasitic components such as, for example, an offset voltage and/or voltage associated with current leakage. The circuitry may adjust the stored voltage to compensate for the parasitic components. The adjustment may occur over a series of phases of operation of the circuitry.

Analog front-end compensation

An arc fault detection apparatus that provides for better discrimination of electrical arcing events from nuisance loads. The arc fault detection apparatus includes an arcing sense circuit having a comparator circuit with a variable threshold voltage that varies continuously with the line voltage. The arc fault detection apparatus has reduced susceptibility to nuisance tripping in the presence of sudden changes in the load current that occur outside of a specified time window centered on each zero crossing point of the line voltage.

Arc fault detection apparatus employing a comparator with a continuously variable threshold

An improved system and method of performing capacitance measurements that provides a fast digital response and a reduced output error. The capacitance measurement system includes a circuit configuration that has a variable capacitor and at least one reference capacitor connected to one another at a common node, which in turn is connected to the input of an analog-to-digital converter. The circuit configuration further includes an array of switches coupled between the variable and reference capacitors and the supply voltage, a reference voltage, and ground, respectively. The switched variable and reference capacitors are employed in conjunction with the A-to-D converter to perform, at the common node, a plurality of direct voltage measurements for use in generating an expression defining the capacitance of the variable capacitor.

Microprocessor-based capacitance measurement

An apparatus and method for detecting arc faults that have reduced susceptibility to nuisance tripping. The apparatus includes a current sensor, an input sense circuit, an arcing sense circuit, a power supply, a tripping (firing) circuit, a processor, and an electromechanical interface. The current sensor monitors a power input comprising an AC current, and provides high frequency components of the. AC current to the input sense circuit. The input sense circuit filters and rectifies the AC signal, and provides the rectified signal to the arcing sense circuit. The arcing sense circuit provides a voltage level accumulated over a predetermined time period, and digital signals indicative of possible electrical arcing occurring during the sampling period, to the processor. The processor measures the voltage level, stores information relating to measured voltages and the digital signals, and processes the stored information using one or more algorithms, thereby determining whether the signals resulted from an arc fault or a nuisance load. In the event the signals resulted from an arc fault, the processor activates the firing circuit to trip the electromechanical interface, thereby interrupting the power output to the load.

Apparatus for detecting arc faults

Method for detecting arc faults

Current flowing through a load is monitored by a transformer (Tr) having a small mutual inductance. The secondary coil is shorted through a rectifier circuit to deliver a charge which, in a first preferred embodiment, is connected to a log charge translator circuit comprising matching diodes (DDand DD) and a capacitor (C) to provide a capacitor voltage proportional to the log of the charge delivered through the rectifier circuit. The capacitor is reset after each measurement. In a modified embodiment, the log translator circuit comprises a pair of transistors (TT) and a capacitor (C). According to the preferred embodiments, two measurements of the capacitor voltage are taken each half cycle at a time determined by the absolute value of the line voltage. The measurements per half cycle are stored in words in a stack and processed through a three or five cycle algorithm for determining fluctuations which will cancel out disturbances caused by nuisance loads that are repetitive or continuously varying. In a described embodiment, a pushdown stack of 60 words is used with fluctuations compared by a microcontroller to a selected limit. Measurements for the last half second of measurements are considered, ignoring the first and last measurement, and when the sum of the fluctuations exceeds the selected limit an arc is indicated and a circuit interrupter is tripped. A self test button is connected to the microcontroller which, when depressed, results in charging of the capacitor to stimulate the detection of an arc.

Arc detection apparatus and method

An ASIC ( ) conditions two independent outputs (VINM, VINP) of a full Wheatstone piezoresistive bridge ( ) in separate conditioning paths. Each path is provided with a bridge supply voltage (VHB , VHB ) which can serve as a temperature related input signal to respective offset and gain compensation control circuits. The half bridge outputs are inputted to respective amplifiers (U , U ) along with a selected percentage of the temperature dependent bridge supply voltage. The outputs of the amplifiers provide a signal proportional to respective half bridge output voltage. In one embodiment, the output of the amplifier (U ) in one conditioning path of one half bridge is connected to the input of an amplifier (U ) in the other conditioning path to provide a signal in the one path proportional to the Wheatstone bridge differential output voltage and in the other path a signal proportional to the Wheatstone half bridge output voltage. In another embodiment, the temperature dependent bridge supply voltage is multiplexed for a selected time upon power-up to an amplifier (U ) which normally receives an input from one of the bridge outputs.

Low cost asic architecture for safety critical applications monitoring an applied stimulus

A differential pulse transformer having a drive coil ( ) and differential sense coils ( ) are disposed on a planar surface with a target ( ) movable over the sense coils to cause an imbalance in magnetic field when a large di/dt pulse is generated in the drive coil. A detection circuit senses the imbalance and provides a digital output accurately identifying the position of the target. Coil and target embodiments include relatively small secondary coils and relatively long targets ( and ) and relatively large secondary coils and short targets ( and ).

Digital inductive position sensor

An in-range fault detection system for a full wheatstone bridge element ( ) having piezoresistive elements (R , R , R , R ) has bridge outputs (INP, INM) connected to measuring means in the form of a first circuit portion ( ) to provide a common mode voltage (V ). A second circuit portion ( ) is used to provide a centering voltage (C*V ) equal to the common mode voltage at the time of sensor calibration and a third circuit portion ( ) is used to provide a small window voltage (W*V ) which is a fraction of bridge voltage. The value (W*V ) is subtracted from (C*V ) at a first summing circuit (SUM ) and added to (C*V ) at a second summing circuit (SUM ) and the results are each compared to the common mode voltage by comparators (Q , Q ) which are then determined to be within or without a window of valid values by an OR gate (Q ).

Method and apparatus for in-range fault detection of condition responsive sensor

A capacitive transducer (10) which provides an output voltage in response to the application of a mechanical stimulus such as pressure or acceleration includes a signal conditioning integrated circuit (12) to which are connected a variable capacitor (C.sub.VAR), a reference capacitor (C.sub.REF), a linear correction capacitor (C.sub.LIN) as well as an integrating capacitor (C.sub.INT) and associated filtering components. The linear correction capacitor (C.sub.LIN) is used to offset a fixed parasitic charge associated with the variable capacitor. Any net error charge appearing on a detect, common node (pin 4) between the variable capacitor and the reference capacitor is cancelled out by means of an analog feedback network (22). In a modified embodiment a thermal compensation network (40) allows for correction for thermal error at a second temperature without having any affect at a first temperature.

Sensor with improved capacitive to voltage converter integrated circuit

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Attleboro Falls, MA, United States of America

Keith W Kawate