814 results about "Voltage transducers" patented technology

The present invention provides a system for operating a power line communications system that employs surface wave communications and conducted communications. The system is comprised of a plurality of network elements, which may take the form of repeaters, communication interface devices, backhaul devices, medium voltage transducers, distribution points, aggregation points, and others. In one embodiment, surface waves are communicated over the medium voltage power lines and the conducted communications are communicated via the low voltage power lines to and from customer premises.

Apparatus and method for stimulating neuromuscular tissue in the stomach. The neuromuscular stimulator stimulates the neuromuscular tissue by applying current-controlled electrical pulses. A voltage sensor detects the voltage across the neuromuscular tissue to determine if the voltage meets a predetermined voltage threshold. A control circuit adjusts the current-controlled pulse if the voltage is found to meet the voltage threshold, such that the voltage does not exceed the voltage threshold. A voltage-controlled pulse may also be applied to the tissue. A current sensor would then detect whether the current on the neuromuscular tissue meets a predetermined current threshold, and a control circuit adjusts the voltage controlled pulse such that the current does not exceed the current threshold. A real time clock may be provided which supplies data corresponding to the time of day during the treatment period. A programmable calendar stores parameters of the stimulating pulse, wherein the parameters have a reference to the time of day.

A mobile host device configured to draw electrical energy from an energy storage device includes a disk drive. The disk drive includes a disk drive enclosure including a base, a spindle motor attached to the base, a disk positioned on the spindle motor, a generator and a charging circuit. The generator may be coupled to the disk drive enclosure and/or the mobile host device and generates electrical energy from the motion of the mobile host device and/or disk drive. The charging circuit is configured to charge the energy storage device using the electrical energy generated by the generator.

An ECU detects an effective value and phase of a voltage from a commercial power supply, based on a voltage from a voltage sensor. Further, ECU generates a command current, which is a command value of current caused to flow through power lines and in-phase with the voltage of the commercial power supply, based on the detected effective value and the phase and on a charge/discharge power command value for a power storage device. Then, ECU controls zero-phase voltage of inverters based on the generated command current.

The invention discloses an intelligent electric meter with a function of detecting power supply reliability and a voltage qualified rate and a detecting method of the intelligent electric meter with the function of detecting the power supply reliability and the voltage qualified rate. The intelligent electric meter comprises a voltage sensor and a current sensor, and the voltage sensor and the current sensor are connected with a sampling circuit through a signal adjusting circuit; the sampling circuit is connected with a digital signal processor (DSP); and MCU is simultaneously connected with the DSP, a data memorizer, a power supply module, a local input/output (I/O) module, a remote communication module and a hardware clock. Alternative current voltage data which are collected by the intelligent electric meter not only are used for electric energy measuring and statistics, but also are used for detection and statistics of the power supply reliability and the voltage qualified rate by conducting classification, timing and accumulation on different ranges where the voltage values locate such as an over upper limit range, a qualified range, a over floor level range, a decompression range, the intelligent electric meter is enabled to possess the function of detecting the power supply reliability and the voltage qualified rate, and applied range of the intelligent electric meter is widened.

A solid state power controller system can include a direct current load, a solid state power controller apparatus including an alternating current sensor coupled to the direct current load, a direct current sensor coupled to the direct current load, a voltage sensor coupled to the direct current load, a main switch coupled to the direct current load via the alternating and direct current sensors, an auxiliary switch coupled in parallel to the main switch, a current limiting resistor coupled in series to the auxiliary switch and a solid state power controller coupled to the main switch, the auxiliary switch, the alternating current sensor, the direct current sensor, and the voltage sensor, and a direct current power source coupled to the solid state power controller apparatus.

An inverter controller for driving a brushless DC motor, of which rotor is provided with permanent magnets, includes an inverter circuit, a position sensing circuit, a DC voltage sensor, and a conduction angle controller. The inverter circuit is connected to the brushless DC motor for driving this motor. The position sensing circuit senses a rotor position with respect to a stator from an induction voltage of the brushless DC motor. The DC voltage sensor senses a voltage value of a DC power voltage supplied to the inverter circuit. The conduction angle controller changes a conduction angle of the inverter circuit within a range less than 180 degrees in electric angles in response to a rate of change in the DC power voltage.

The invention discloses a rectification control circuit for a bidirectional CLLLC resonant converter. Both the primary side and the secondary side of the transformer in the bidirectional CLLLC resonant converter are connected to a current transformer, and the current on the power receiving side of the transformer is sampled, and It is converted into a voltage signal through a unit resistance, and connected to the inverting input terminals of two hysteresis comparators through a voltage sensor. The output signals of the two hysteresis comparators respectively drive the leading switch and the lagging switch on the power receiving side to realize MOSFET rectification. Since the on-resistance of the MOSFET is very small, the rectification control circuit for the bidirectional CLLLC resonant converter of the present invention reduces the rectification loss and improves the overall efficiency of the converter compared with diode rectification.

A charge control ECU stops a charge converter periodically or at a predetermined timing, and detects the open-circuit voltage of a solar cell through a voltage sensor. The charge control ECU uses a preset relational expression or map to determine the operating voltage corresponding to a maximum output power from the solar cell based on the detected open-circuit voltage. The charge control ECU causes the charge converter to resume its operation when the determined operating voltage is set at the charge converter as the target voltage.

A closed-loop system 10 is provided for controlling a DC motor. The system includes a DC motor 12, a controller 18 associated with the motor and constructed and arranged to control operation of the motor, a voltage sensor 14 constructed and arranged to measure a voltage supplied to the motor, a speed sensor 16 associated with the motor and constructed and arranged to obtain a measured speed of the motor, and a conditioning circuit 21 constructed and arranged to receive a speed signal and condition the speed signal to provide to the controller, a nominal speed based on the voltage supplied to the motor, or nominal rate of acceleration or deceleration upon a change in the desired speed. The controller 18 is constructed and arranged to compare the measured speed with a certain speed, that is less than the nominal speed, at a voltage corresponding to a measured voltage, and if the measured speed is less than the certain speed, a fault condition is defined by the controller. The controller 18 is also constructed and arranged to compare the measured rate of change of speed with a desired rate of change of speed, that is more than the nominal rate of change of speed in the case of motor acceleration, or less than the nominal rate of change of speed in the case of deceleration, at a voltage corresponding to a measured voltage, and if the measured rate of change of speed differs significantly from the expected rate of change of speed, a fault condition is defined by the controller.

The invention relates to a small earth current grid single-phase grounding fault wire-choosing method, which comprises: 1) Collecting the zero order voltage and the zero order current signal on the voltage sensor and the current sensor of each wire and computing the zero order voltage amplitude, if the amplitude is over the limit, it quotes that it occurs the fault and collects the zero order current after four period of the fault; 2) computing the second, third and forth period effect value I1, I2 and I3 when each line zero order current fault starts and computing the gradient factor K1, K2 of each line zero order current; 3) quoting weather it satisfies K1ú¥KSET and K2ú¥KSET, wherein KSET is the gradient factor setting value with the range 1.2-2.0; 4) if it satisfies K1ú¥KSET and K2ú¥KSET, the wire is earth fault wire. The wire-choosing system comprises a microcomputer including a fault detecting open unit, a zero order current gradient computing unit and a transient gradient wire-choosing unit.

A system (10) is provided herein for monitoring the harmonic content of the RF signal delivered to an RF powered device (13). The system comprises (a) a voltage transducer (16) adapted to sample the voltage of the RF signal and to output a first signal representative thereof, (b) a current transducer (17) adapted to sample the current of the RF signal and to output a second signal representative thereof, and (c) a memory device (67) in communication with at least one, and preferably both, of the aforementioned transducers 16 and 17 and which contains calibration information specific to the transducers.

The invention provides a ground fault line selecting method for a small current grounding system. The method comprises the steps that a zero sequence voltage transformer and a zero sequence current transformer respectively acquire zero sequence voltage signals and zero sequence current signals when the small current grounding system encounters faults, a secondary voltage transducer and a secondary current transducer convert the zero sequence voltage signals and the zero sequence current signals into measurement signals for fault line reorganization respectively, the measurement signals are processed by a programmable operational amplifier and then are transmitted to an FPGA module, the FPGA module controls an AD sampling module to carry out high-speed synchronous sampling, sampling code stream data obtained through the sampling of the FPGA module are transmitted to an embedded processor in a DMA mode, the embedded processor processes the sampling code stream data, and ground fault line selection detection is carried out. According to the ground fault line selecting method for the small current grounding system, an FPGA is utilized for controlling an AD sampling chip to achieve the high-speed sampling, DAM communication between the embedded processor and the FPGA module is achieved, data throughput capacity is improved, and the embedded processor is made to have more resources for integrated application of judgment logic of various fault line selection algorithms.

Systems and methods for detecting faults in RVDTs and LVDTs are described. In an exemplary embodiment, a sum of secondary voltages V1 and V2 from a transducer is obtained by adding the secondary voltages together, i.e.; V1+V2. This sum of secondary voltages theoretically should be constant for all LVDT/RVDT positions, since the total length of the secondary transformer is constant. An electrical fault in the primary or secondary windings generates a corresponding change in the sum of secondary voltages. By comparing this shifted value to a reference value which is representative of a no-fault condition, an error value is created which indicates the magnitude of the shift in the sum of the secondary values. Depending upon the magnitude of the error value, certain actions are taken.

The invention discloses an MMC module voltage measuring and fault locating method based on state monitoring. Output ports of two adjacent single-capacitor modules in serial connection or a double-capacitor module serve as voltage collecting points, one voltage sensor or measuring circuit can measure the voltages of two modules, the amount of sensors or circuits is greatly reduced, and hardware cost and complexity are reduced. The measuring method can be used for voltage correction, errors caused by difference in parameters as the capacitance are avoided, whether a module has faults can be determined according to the obtained voltage and module state, and the system locates the module according to a fault signal emitted by the fault module. The module voltage measuring and fault locating method is realized in a module controller, the computing load of a main controller is not increased, and the hardware requirement is lowered. The module voltage measuring and fault locating method is suitable for high-voltage large-power occasions in which multiple MMC modules are included, such as the fields including energy Internet and high-tension DC power transmission.

An induction motor controller that may include three phase paths leading from a power input to a power output, a solid-state switching device interposed between the power input and the power output on each of the three phase paths, a voltage sensor coupled to two of the phase paths between the solid-state switching device and the power output, a current sensor on one of the phase paths, a processor communicatively coupled to the voltage sensor, the current sensor, and the solid state switching device; and a memory coupled to the processor. The processor may be configured to calculate a motor parameter based on a signal from the voltage sensor and a signal from the current sensor and store the calculated motor parameter in memory.

The invention relates to a condition monitoring system used for a ring main unit of an intelligent power distribution network. The system comprises a data acquisition analysis processing unit, a divide-shut brake current sensor, a divide-shut brake voltage transducer, an operating pressure sensor, a travel sensor, a vibration sensor, a temperature sensor, and a partial discharge sensor, wherein the divide-shut brake current sensor, the divide-shut brake electric pressure transducer, the operating pressure sensor, the travel sensor, the vibration sensor, the temperature sensor, and the partial discharge sensor are accessed to the data acquisition analysis processing unit. The system provides a uniform platform for the power distribution network switch device on-line monitoring system and acquires divide-shut brake electrical current, operating voltage, operating pressure, contact temperature, contact terminal travel, and partial discharge condition of the accessed switches through the switch on-line monitoring device so as to realize on-line monitoring and global analysis for overall conditions of power distribution network switches. Therefore, the on-line monitoring system for the power distribution network switches, which provides uniform data, uniform interface and uniform arrangement and realizes effective data interaction, is provided.