2138 results about "Current transducer" patented technology

A contactor for connecting a medium voltage load, such as a medium voltage three-phase motor, to a medium voltage electrical source, such as a medium voltage three-phase electrical source, and for providing protection functionality for the load includes one or more electrical conductors each having separable contacts such that the load is selectively electrically connected to the source, and one or more current transducers each operatively coupled to a respective one of the electrical conductors for measuring a current thereon. A processor is in electronic communication with the one or more current transducers, and a memory is in electronic communication with the processor. The memory stores one or more routines executable by the processor that are adapted to perform one or more protection functions for the load based on the current measured by each of the one or more current transducers and to selectively open and close the separable contacts of each of said electrical conductors.

A circuit interrupter includes separable contacts, a neutral conductor, an operating mechanism structured to open and close the separable contacts, and a plurality of current sensors structured to sense at least current flowing through the separable contacts. Each of the current sensors includes a primary winding and a secondary winding, the primary winding being electrically connected in series with the separable contacts. A trip mechanism is structured to cooperate with the secondary winding of the current sensors and the operating mechanism to trip open the separable contacts. A test circuit tests the current sensors and the trip mechanism. The test circuit is structured to apply a test signal directly to the secondary winding of each of the current sensors.

The invention relates to an energy transfer type power battery quick balancing system and a control method thereof. The invention relates to the battery voltage balancing system and further relates to the control method of battery pack quick balancing process, which solves the problem that a balanced battery single body and an energy storing element are impacted through pulse current by a currentbalancer in the prior art. The system comprises a power battery pack single body battery voltage and flying capacitor voltage detecting network, a current sensor and a signal modulating circuit, a single chip microcomputer, an electric power transfer channel, a first filter circuit, a two-way buck-boost converter, a second filter circuit and a flying capacitor. After starting to work, the system firstly detects the battery pack single body battery voltage, the flying capacitor voltage and the charging/discharging current; and if the dropout voltage between the highest voltage of the battery single body and the lowest voltage of the single body exceeds a set value, the balancing operation is started.

When a rectangular wave voltage control mode is selected, a control apparatus estimates the output torque of an alternating-current motor based on the outputs of a current sensor and a rotation angle sensor, and executes torque feedback control by adjusting the phase of rectangular wave voltage based on the difference between the torque estimated value and a torque command value. The control apparatus executes a switching interruption that outputs a control command to a switching element of an inverter every 60 degrees of electrical angle, and executes an angle interruption that samples the phase currents of the alternating-current motor based on the output of the current sensor and converts those phase currents into a d-axis current and a q-axis current every predetermined electrical angle that is set beforehand. The control apparatus for the alternating-current motor then sets the predetermined electrical angle such that the number of angle interruptions between switching interruptions varies according to the rotation speed of the alternating-current motor.

A presently-preferred embodiment of an electrical-energy meter comprises a base adapted to be mounted on a supporting surface, a current sensor assembly comprising a plurality of contact blades extending through the base and adapted to electrically contact a conductor of electrical energy, and a current transformer mechanically coupled to the base and electrically coupled to the contact blades. The electrical-energy meter further comprises a circuit board assembly comprising a main circuit board electrically coupled to the current transformer and the contact blades. The electrical-energy meter also comprises a circuit-board support member comprising a rim portion fixedly coupled to the base, and a first bracket adjoining the rim portion. The first bracket has a first and a second leg each extending away from the rim portion and the base and each being adapted to securely engage the main circuit board.

The invention provides an intelligent control system and a control method for a scraper conveyer, which belong to the intelligent control systems for coal mine exploitation. The intelligent control system for the scraper conveyer comprises a laser scanning ranging device, a ray ranging transmitter, an ultrasonic level sensor, a current transducer, a master controller, a variable frequency and speed regulation controller, a coal crushing controller, a conveyor gesture controller and a conveyor chain stretching controller, wherein the laser scanning ranging device, the ray ranging transmitter, the ultrasonic level sensor and the current transducer transmit detection signals to the master controller in a wireless communication manner, and the master controller sends control instructions to the variable frequency and speed regulation controller, the coal crushing controller, the conveyor gesture controller and the conveyor chain stretching controller in the wireless communication manner. The running state of the scraper conveyer is mastered at any time and corresponding devices are controlled timely through monitoring of the laser scanning ranging device, the ray ranging transmitter, the ultrasonic level sensor and the current transducer, so that the scraper conveyer can be operated in an optimum running state.

A current sensor for detecting a first electric current flowing through a current path includes a sensor chip, a coil, a current control circuit, and an output circuit. The sensor chip includes a magnetoresistive element and is adopted to be located near the current path. The coil applies a bias magnetic field to the magnetoresistive element. The current control circuit supplies a second electric current to the coil. The second electric current periodically changes in polarity. The output circuit outputs a difference between a first voltage and a second voltage. The first voltage is generated by the magnetoresistive element, when the second electric current flowing through the coil has a positive polarity. The second voltage is generated by the magnetoresistive element, when the second electric current flowing through the coil has a negative polarity.

The invention relates to an electric current reconstructing and over-modulating device of an air conditioning frequency converter, which is characterized by comprising an electric current reconstructing device, a vector controller, a pulse width modulation (PWM) frequency converter, a direct current side electric current sensor, an electric motor and a coder. The electric current reconstructing device comprises an SVPWM over-modulating module, a pulse width modulation (PWM) signal adjusting module, a direct current sampling module and an alternating current reconstructing module. An electric current reconstructing and over modulating method of the air conditioning frequency converter comprises the steps: sampling the direct current side electric current of the pulse width modulation (PWM)frequency converter at twice by the electric current reconstructing device; counting an approach vector switch action time which meets a minimum sampling time request according to the two sampling values; sampling the direct current side electric current at twice again in the approach vector switch action time; and reconstructing three phase alternating current according to the sampling values ofthe direct current at twice, thereby realizing the closed loop control of the pulse width modulation (PWM) frequency converter. The modulating method can be widely used for the field in reconstructingand over-modulating the electric current of the frequency converter in air conditionings and electric vehicles.

A vehicle (1) comprising a chargeable/dischargeable battery (B1), a current sensor (11-1) for detecting the current from the battery, and a control unit (30) for estimating the charged state of the battery and controlling the charging/discharging of the battery according to the charged state. In a first operation mode in which charging and discharging cycles are repeated, the control unit (30) estimates the open-circuit voltage of the battery, and determines the charged state on the basis of the value which is obtained by correcting the open-circuit voltage according to the polarization. In asecond operation mode in which either one of charging and discharging is continued, the control unit (30) determines the charged state on the basis of the result of integration of the current detected by the current sensor. Hence, the charged and discharged amperehours are large, thereby providing a vehicle which can effectively utilize the secondary battery.

A non-isolated power supply is configured to receive an input voltage and supply an output voltage, and includes a supply line, a return line, a first semiconductor switch coupled in series in the supply line, and a second semiconductor switch coupled in series in the return line. The first and second semiconductor switches are each configured to operate in an ON state and an OFF state. The differential current sensor is configured to sense differential current between the supply line and the return line. The fault detection logic is coupled to the differential current sensor, the first semiconductor switch, and the second semiconductor switch, and is configured to detect when the differential current exceeds a predetermined current magnitude, and command the first and second semiconductor switches to operate in the OFF state upon detecting that the differential current exceeds the predetermined current magnitude.

A monitoring system for monitoring the temperature and vibration of equipment, comprising a central digital computer, a MESH communication network, wherein the network feeds signals to the central digital computer, a plurality of heating elements for heating the equipment, temperature/vibration sensors adapted to measure the temperature of the equipment, wherein each sensor is adapted to provide a signal representing the temperature/vibration of the piece of equipment to which the sensor is associated, to the network, wherein each temperature/vibration sensor can also be used to control the electric heaters, a temperature sensor that monitors the ambient temperature of the facility, and current transducers associated with the heaters, to monitor the energy use and current loss of the heaters, wherein the central computer uses the data it receives from the other elements of the monitoring system to determine when the equipment is not at the correct temperature/vibration and diagnoses the reason why.

The invention concerns a current transducer for measuring a current flowing through a cable, comprising at least one magnetic field sensor and an electronic circuit. The current transducer comprises a head with a ferromagnetic core optimized to reduce the effects of external magnetic fields. The invention further concerns a magnetic transducer comprising a magnetic field sensor and an electronic circuit. The electronic circuit comprises at least one current source, a transformer, a fully differential preamplifier coupled to the transformer, a phase sensitive detector coupled to the preamplifier and a logic block configured to operate the magnetic field sensor(s) to provide an AC output voltage. The magnetic field sensor(s) is preferably either a Hall element or an AMR sensor or a flux-gate sensor.

A method and system for measuring electric current in a plurality (n) of conductors. According to the invention, the method comprises the following steps: an electric current transducer is place substantially opposite to each conductor (I, i=1, . . . , n); a decorrelation matrix ([G]), which is a function of the position of the transducers in relation to the conductors, is constructed; the current (I_mesi) in each conductor (i) is measured with the aid of electric current transducers and real currents (I_reeli) are deduced with the aid of the decorrelation matrix ([G]) and the measured currents (I_mesi).

An intelligent auxiliary power supply system for supplying power to a load such as a furnace or air handler using a rechargeable power source. An intelligent controller determines appropriate periods for switching to auxiliary power, thus allowing the user to realize increased energy related cost savings. A plurality of sensors including a current transducer, an indoor and outdoor temperature sensor, and a clock transmit information to the intelligent controller. Implementing user configured algorithms, the intelligent controller continuously compares information transmitted from said sensors and said load, to information inputted by the user via an electronic device to determine the appropriate power configuration. A remote electronic device may also be connected to the system, allowing the user to control the system while not in close proximity to said system and also allowing the user's energy provider to send requests to switch to auxiliary power.

The invention relates to a method for realizing an electric auto-passing neutral section of a train by utilizing a power electronic switching device and belongs to the technical field of the manufacturing of the power electronic switching device. An existing modern power electronic technology, namely a high-power voltage current transducer control technology, is adopted to realize the complete equipment of power electronic switching device which is used as a 'phase-change switch for a ground auto-passing neutral section device', thereby optimizing an existing 'uninterrupted automatic electricphase-separating system for electrically dragged train', exactly realizing an uninterrupted automatic electric phase-separating function of an electrically dragged railway train and overcoming inherent defects of technical performance of an original system.