972results about "Voltage dividers" patented technology

A semiconductor device includes: a semiconductor substrate; a high-voltage first resistive structure which extends along a spiral path above the substrate and is separated from the substrate by a first dielectric layer; and a conductive shielding structure, including a plurality of first shielding strips, which are arranged in sequence along respective portions of the first resistive structure and are separated from the first resistive structure by a second dielectric layer.

A battery voltage monitoring apparatus monitoring an assembled battery voltage, the assembled battery including a plurality of battery cells, includes a voltage sensor detecting potential of the plurality of battery cells; an output logic circuit outputting a potential detect signal based on an output of the voltage sensor, the potential detect signal representing that abnormal potential is detected; and a delay circuit adding certain delay to the output of the voltage sensor and outputting the delayed voltage detect signal to the output logic circuit; wherein, the voltage sensor comprises at least one comparator having hysteresis characteristic, and detects the potential of the battery cell based on an output of the comparator.

A voltage detection device detects an objective AC voltage arising on a detection object. The voltage detection device includes; a detecting electrode placed so as to be capacitively coupled with the detection object; a reference signal output section for outputting a reference signal; a detecting section outputting a detection signal changing its amplitude in accordance with both current values of a detection object current flowing according to the objective AC voltage and a reference current flowing according to the reference signal; and a signal extracting section for extracting a signal component of the objective AC voltage from an amplified detection signal and outputting the signal component as an output signal, the amplified detection signal being obtained through controlling a gain for amplifying the detection signal so as to make a signal component of the reference signal included in the detection signal have a predetermined value.

The present invention relates to voltage measurement apparatus. The voltage measurement apparatus comprises a potential attenuator configured to be electrically connected between first and second conductors, which are electrically coupled to a source. The potential attenuator comprises a first impedance and a reference impedance arrangement in series with each other. The reference impedance arrangement has an electrical characteristic which is changed in a known fashion. The voltage measurement apparatus further comprises a processing arrangement configured: to acquire at least one signal from the reference impedance arrangement, the at least one signal reflecting change of the electrical characteristic in the known fashion; and to determine a voltage between the first and second conductors in dependence on the fashion in which the electrical characteristic is changed being known and the at least one signal.

Disclosed herein is a voltage monitoring method and circuit for an electrical energy storage device. The voltage monitoring method includes detecting the voltages of one or more unit cells constituting the electrical energy storage device; generating logical signals depending on the respective levels of the detected voltages; and generating a detection signal indicating whether the unit cells are abnormal in response to the logical signals.

Described herein is a method and apparatus for measuring the potential on a modern shielded high-voltage cable such as those used in medium-voltage distribution networks. A capacitive sensor arrangement (100) is constructed on a cable (110) using pre-existing structures (114, 116, 118, 120) within the cable (110). The use of implicit guarding methods is also described that allows the use of the semiconductor layer (116) present in modern cable design to be retained and to form part of the capacitive sensor arrangement (100). Performance of the sensor arrangement (100) can also be improved using temperature compensation techniques.

An embodiment of a voltage-measuring circuit includes: a first resistor connected to a first measurement node; a second resistor connected to the first resistor and a second measurement node; a configuration switch configured to, in response to a control signal, selectively interconnect the first and second resistors, during enable and disable phases of the control signal respectively, into and out of either a parallel or a series configuration; and a control and measurement circuit configured to provide the control signal, receive a first measurement voltage from the first and second measurement nodes during the enable phase, and receive a second measurement voltage from the first and second measurement nodes during the disable phase.

A method of digitally correcting the raw output voltage from a Capacitive Voltage Transformer (CVT) with the intent to remove transient components impacting on transient accuracy of protection function. A typical CVT is represented using three parameters in the linear CVT model. A digital filter designed based on the three parameters and incorporating a dedicated mechanism to ensure numerical stability of the former. A method of self-adjusting the said filter based on system events and performed after the method has been deployed in the field and supplied from a specific CVT.

The invention discloses a device for condition monitoring and fault diagnosis of a high-voltage switch. The device comprises a monitoring unit and a control unit, wherein the monitoring unit takes a cathode capable of outputting high-voltage direct current as a floating sampling datum point, and takes an input port and an output port of each high-voltage switch in a high-voltage direct current output loop as sampling points, and a voltage value of each sampling point is detected through a multi-channel high-voltage detection circuit; the control unit is used for sending a switch command to the high-voltage switch, and carrying out condition monitoring and fault diagnosis on the high-voltage switch according to the switch command and the voltage value of each sampling point. According to the device for condition monitoring and fault diagnosis of a high-voltage switch provided by the invention, condition monitoring and fault diagnosis of a high-voltage direct current system are realized, and safety and reliability of the high-voltage direct current system are improved.

An indicator system having light emitting diode (LED) indicators and an open-circuit detecting circuit. In the open-circuit detecting circuit, a voltage at a point between a constant current source and the first resistor is applied to a base of a transistor. The second resistor is connected in parallel between the base and an emitter of the transistor. The third and the fourth resistors are connected in series between the constant current source and a collector of the transistor. The fifth resistor is connected between the emitter of the transistor and the first resistor. The threshold determining circuit determines a voltage at a point between the third and the fourth resistors as a threshold voltage. With this configuration, the threshold voltage can be adjusted according to the resistance of the first resistor.

The invention relates to a capacitor voltage transformer suitable for high-voltage harmonic measurement and a measurement method. The capacitor voltage transformer is characterized in that a current transformer is respectively connected into a low-voltage capacitance branch and an intermediate transformer branch of a capacitive voltage divider of the capacitor voltage transformer in series, two conventional current transformers are additionally arranged in a conventional capacitor voltage transformer, and the size and the phase position of harmonic voltage of a high-voltage system can be worked out by using electric currents measured by the two current transformers. Therefore, the capacitor voltage transformer has the advantages of being simple in structure and convenient to realize, having high measurement accuracy of voltage harmonics, being free of influence of the size of a load of the capacitor voltage transformer and having very high application value and market promotion prospect in occasions where high-voltage harmonics are measured.

A system and device for measuring voltage in a conductor having a voltage provides a first electrode surrounding and spaced from the conductor, and a second electrode surrounding and spaced from both the conductor and the first electrode such that there is no contact between the conductor and the electrodes or between the first and second electrodes. The first electrode is connected to a first input of a differential amplifier circuit and the second electrode is connected to the other input of the differential amplifier circuit. The output of the differential amplifier circuit provides a voltage signal in proportion to the voltage of the conductor, thus providing a non-contact means for measuring the voltage of a conductor without requiring a connection to ground while simultaneously providing a high level of rejection of external interference.

The embodiment of the invention discloses a method and circuit for detecting ground insulation impedance of a photovoltaic array. The circuit is composed of a positive voltage division circuit and a negative voltage division circuit, wherein the resistance ratio of the positive voltage division circuit to the negative voltage division circuit is at least N1, N2, N3 and N4; and N3 is greater than 1/5 but less than or equal to 1/N4, N1 is greater than 1/N4 but less than or equal to 1/N2, and 1/N2 is greater than or equal to N1 but less than 1. The method for detecting the ground insulation impedance of the photovoltaic array comprises the steps of: respectively connecting the positive voltage division circuit and the negative pressure division circuit between a positive bus and a ground line and between the ground line and the negative bus during the detection; when a bus voltage is not greater than the product of a maximum output voltage of the photovoltaic array and the N1, adjusting the positive voltage division circuit and/or the negative voltage division circuit to enable the resistance ratio to be respectively N1 and N2; calculating the ground insulation impedance value of the photovoltaic array based on a serial partial pressure principle; and when the bus voltage is greater than the product, selecting the N3 and the N4 for corresponding operation and calculation so as to obtain a ground insulation impedance value. According to the embodiment of the invention, the problem that the ground insulation impedance cannot be detected exactly within a full voltage range when the differential value of the ground insulation impedances of the positive bus and the negative bus is very great in the prior art is solved.

A secondary-battery monitoring device capable of realizing highly reliable overcurrent detection and a battery pack having it are provided. When an overcurrent flowing to a secondary battery is to be detected by utilizing a current detection voltage generated via on-resistance of a discharge-control switch and a charge-control switch, a voltage correction circuit that generates a correction voltage having a characteristic varied by positive slope or negative slope along with increase in a power supply voltage is provided, and the correction voltage is added to the detection voltage or a reference power supply voltage with the polarity that cancels out the slope of voltage variation caused in the detection voltage, and then the voltage is input to a comparator circuit. In this manner, variation in the overcurrent determination current is reduced.

An intelligent electronic device (IED), e.g., an electrical power meter having circuitry for an input voltage structure with an adjusting voltage divider, resulting in a highly accurate power measurement, is provided. The IED includes a first voltage input for receiving a sensed voltage from a first phase of an electrical distribution system, the first voltage input being coupled to a first voltage divider; a second voltage input for receiving a sensed voltage from a neutral phase of the electrical distribution system, the second voltage input being coupled to a second voltage divider; and an inverting operational amplifier (op amp) coupled to the first and second voltage inputs for providing an output proportional to the voltage of the first phase referenced to the neutral phase, wherein the first voltage divider is adjustable to match a ratio of the first voltage divider to a ratio of the second voltage divider.

A voltage sensor is described that consists of an arrangement of impedance elements. The sensor is optimized to provide an output ratio that is substantially immune to changes in voltage, temperature variations or aging. Also disclosed is a material with a large and stable dielectric constant. The dielectric constant can be tailored to vary with position or direction in the material.

The invention relates to an overvoltage sensor of overhead transmission lines, relating to an overvoltage monitoring device of the overhead transmission line of an AC power system. The sensor consists of a voltage monitoring unit and a data acquisition unit, and is characterized in that the voltage monitoring unit mainly comprises an overhead transmission line, a sensing metal plate, a screening shell, a stainless steel screening box, a voltage-dividing capacitor, a front end protection circuit, a matched resistance, a coaxial-cable and the like. The sensor has the effects of simple structure, small volume, light weight, convenient installation, low cost, high safety, good universality, high linearity and high accuracy on testing overvoltage and the like. The invention can be widely used as the voltage sensor of the overhead transmission line, especially be applicable to overvoltage sensor of 10kV to 1000kV overhead transmission lines.

The invention discloses an intelligent electronic type voltage transformer. The intelligent electronic type voltage transformer comprises a far-end module, an amorphous iron core, an optical fiber composite insulator, an insulating oil layer, a resistance-capacitance voltage divider, an optical fiber and a combination unit. According to the intelligent electronic type voltage transformer, the iron core is made of amorphous materials, a resistance-capacitance voltage division principle is used as a design principle, and a transformer body is formed by pouring insulting silicone rubber on the amorphous iron core, a primary winding and a secondary winding. According to the intelligent electronic type voltage transformer, the iron core is made of amorphous alloy, so that the intelligent electronic type voltage transformer has high saturated magnetic induction and low loss, the weight and the size of the intelligent electronic type voltage transformer can be reduced greatly, and efficiency can be improved greatly. In addition, the intelligent electronic type voltage transformer has low noise, is easy and convenient to install and use, does not need maintaining in an operation process, is light in weight, high in accuracy, good in linearity and wide in measuring range, overcomes the defects that a conventional electromagnetic voltage transformer is narrow in frequency band, slow in response and the like, and has practical significance to transformation of and improvement to existing electrical equipment, and the ability to resist electromagnetic interference is enhanced.

Accurate harmonic measurements on electrical power systems where the main instrument transformers are of the capacitor coupled voltage type (CVT type) is made possible by the provision of one or more current sensors (PQCS1, PQCS2). CVTs typically have a high voltage capacitor bank (CH) and a low voltage capacitor bank (CL). One or more current sensors (PQCS1, PQCS2) is/are positioned so as to measure capacitor current and from that the input voltage (Vin) of the CVT can be determined for each frequency.

The invention discloses a voltage detection circuit which can be used for detecting a lower first voltage power source and a higher second voltage power source. The same resistance detection circuit is used by both the higher voltage power source and the lower voltage power source, and a first voltage detection end which is separated from the resistance detection circuit is connected with a voltage protection circuit and then connected to a follow-up first comparator. The voltage protection circuit comprises a first N-channel metal oxide semiconductor (NMOS) tube with a high voltage and a transistor tandem cascading structure which is formed by connecting a plurality of diode-connected metal oxide semiconductor (MOS) tubes in series. When a high-pressure alarm is carried out, the voltage protection circuit enables the high voltage of the first voltage detection end to be released, the voltage which is input to the first comparator is enabled to be clamped in a low voltage and the first comparator is enabled to be produced by low-pressure devices, thus the speed of a low-pressure alarm is improved and the area of circuits is reduced. The voltage detection circuit is capable of greatly reducing the area of the circuits further by sharing the resistance detection circuit.

The invention relates to a high pressure pulse resistance voltage divider which can reduce the reaction time of the resistance voltage divider and improve the function of the voltage divider. The outer shield radar dome (9) of the voltage divider is a hollow pipe-type which possesses a first stage high pressure arm resistance (1); the insulated bushing (2) is covered out the first stage high pressure arm resistance (1); the pad electrode (3) is covered on one end of the insulated bushing (2); the high pressure arm frame (4) on the two ends of the insulated bushing (2) is supported inside the outer shield radar dome (9); the high pressure input end (10) is connected with the out end of the first stage high pressure arm resistance; the pad electrode (3) is connected with the inner end of the first stage high pressure arm resistance; the first stage low pressure arm resistance, the second stage high pressure arm resistance, the second stage low pressure arm resistance, and the divider output end are positioned between the outer shield radar dome (9) and the high pressure arm frame (4).