29170 results about "Three-phase" patented technology

This invention improves the performance and lowers the cost of DC to AC inverters and the systems where these inverters are used. The performance enhancements are most valuable in renewable and distributed energy applications where high power conversion efficiencies are critical. The invention allows a variety of DC sources to provide power thru the inverter to the utility grid or directly to loads without a transformer and at very high power conversion efficiencies. The enabling technology is a novel boost converter stage that regulates the voltage for a following DC to AC converter stage and uses a single semiconductor switching device. The AC inverter output configuration is either single-phase or three-phase.

A process that assists a computer programmer to perform an upgrade to a computer program while that program continues to operate and provide service. The upgrade process includes three phases: (1) the preparation by a computer programmer of a new computer program P'' that is to replace an existing computer program P, (2) an offline preparation of the upgrade from P to P'' with the assistance of the computer programmer, and (3) an online, fully automatic, live upgrade from P to P''.

A galvanic isolated DC-DC and DC-AC power conversion system is coupled to a plurality of DC sources which are derived from a combination of a plurality of single-phase and three-phase AC-DC converters. The DC-DC and DC-AC power conversion system in one embodiment is configured to provide mixed type outputs (mixed frequency, e.g. DC with 50 or 60 Hz, with 400 Hz; mixed voltage levels).

A ceramic article which is resistant to erosion by halogen-containing plasmas used in semiconductor processing. The ceramic article includes ceramic which is multi-phased, typically including two phase to three phases. The ceramic is formed from yttrium oxide at a molar concentration ranging from about 50 mole % to about 75 mole %; zirconium oxide at a molar concentration ranging from about 10 mole % to about 30 mole %; and at least one other component, selected from the group consisting of aluminum oxide, hafnium oxide, scandium oxide, neodymium oxide, niobium oxide, samarium oxide, ytterbium oxide, erbium oxide, cerium oxide, and combinations thereof, at a molar concentration ranging from about 10 mole % to about 30 mole %.

A power converter system advantageously employs a modular, bi-directionally symmetrical power converter assembly in a readily customizable configuration to interconnect a direct current power source to a three-phase alternating power grid. Connections external to the power converter assembly are selected to optimize the power converter system for a specific application, such as interconnecting a photovoltaic array to the three-phase electrical power grid. The electrical interconnections of various elements including isolation transformers, voltage sensors, and control switches are optimized to improve efficiency and reliability.

A photovoltaic system includes a plurality of photovoltaic modules and a DC motor connected to a three-phase generator driven by a shaft. The three-phase generator is connected to a power mains. The electric power supplied to the DC motor by the plurality of photovoltaic modules is repeatedly measured and adjusted, by changing an external excitation current of the DC motor, to the peak power attainable at the current ambient temperature and the current incident solar radiation intensity. The peak power is preferably determined by incrementally changing the excitation current in predetermined time intervals, until the supplied electric power produces a power level which can be regarded as the peak power.

A structured light system for object ranging/measurement is disclosed that implements a trapezoidal-based phase-shifting function with intensity ratio modeling using sinusoidal intensity-varied fringe patterns to accommodate for defocus error. The structured light system includes a light projector constructed to project at least three sinusoidal intensity-varied fringe patterns onto an object that are each phase shifted with respect to the others, a camera for capturing the at least three intensity-varied phase-shifted fringe patterns as they are reflected from the object and a system processor in electrical communication with the light projector and camera for generating the at least three fringe patterns, shifting the patterns in phase and providing the patterns to the projector, wherein the projector projects the at least three phase-shifted fringe patterns sequentially, wherein the camera captures the patterns as reflected from the object and wherein the system processor processes the captured patterns to generate object coordinates.

In a multiple power source system of the present invention that has an inverter connected to a reactance, such as three-phase coils in a motor, a high voltage battery is connected with a low voltage battery via one transistor (Tr2) and one diode (D2) included in the inverter and one phase coil (U-phase coil) of the three-phase motor. The transistor Tr2 is turned on to make the electric current flow from the low voltage battery to the U-phase coil. The transistor Tr2 is subsequently turned off at a preset timing, so that the electric energy accumulated in the reactance, that is, the U-phase coil, flows through the diode D1 into the high voltage battery and thereby charges the high voltage battery. This arrangement enables the charging process from the low voltage battery to the high voltage battery without any complicated circuit structure for the voltage step-up. The three-phase motor may be unipolar driven with transistors connected to one side of the inverter. The arrangement of the present invention does not require any complicated structure, which undesirably increases the size of the multiple power source system, in order to ensure mutual supplement of the electric energy between electric systems having a large difference in voltage, for example, an electric system for driving a hybrid vehicle and an electric system for its control circuit.

An electric arc welding apparatus comprising at least a first consumable electrode and a second consumable electrode movable in unison along a welding path between the edges of two adjacent, mutually grounded plates, a first power supply for passing a first welding current at a first low frequency between the first electrode and the two plates, a second power supply for passing a second welding current at a second low frequency between the second electrode and the two plates, where each of the power supplies includes a three phase voltage input operated at line frequency, a rectifier to convert the input voltage to a DC voltage link and a high frequency switching type inverter converting the DC voltage link to a high frequency AC current, an output rectifier circuit to provide a positive voltage tenninal and a negative voltage terminal, and an output switching network operated at a given low frequency for directing a pulsating welding current at the given low frequency from the two terminals across one of the electrodes and the plates, and a circuit for independently adjusting the given low frequency so the value of the first low frequency of the first power supply is different from the second low frequency of the second power supply.

A negative electrode active material for a nonaqueous electrolyte secondary battery contains a composite material containing three phases, a fine Si phase, a silicon oxide, and a carbonaceous matrix, having coated thereon carbon, and a nonaqueous electrolyte secondary battery using the negative electrode active material.

A system and method for determining the relative phase of each of a plurality of load meters connected to a three-phase power distribution system. The system includes a gateway that communicates information to and from each of the individual load meters. The gateway generates a timing pulse that is received by each of the load meters. Based upon the delay from the receipt of the timing pulse to the next zero crossing of the single phase power supply received by the meter, the utility can determine the phase of the individual meter. The system can include a feeder meter connected to each phase of the electrical supply system to determine the energy consumption for each of the meters connected to a specific phase. The utility can compare the energy consumption information from the feeder meter to all of the load meters connected to the same phase to determine whether any energy theft is occurring.

A microgrid controller may control the generation, distribution, storage and use of electrical power on a microgrid. Embodiments of a microgrid controller may include inputs for different types of power (e.g. AC and DC) or power sources (e.g. wind and solar), an input for utility grid power, electrical equipment for conditioning the electrical power received from the multiple sources (e.g. rectifiers and inverters), outputs to multiple types of loads (e.g. three-phase AC and single-phase AC) and control circuitry designed to control the generation, storage, distribution and usage of electrical power on the microgrid. Embodiments of microgrid systems may include multiple types of electrical generation sources (e.g. wind, solar, electromechanical and fuel cell), multiple types of electrical loads (e.g. inductive and resistive), electrical storage units (e.g. batteries) and a microgrid controller.

A magnetic alloy material according to the present invention has a composition represented by Fe_100-a-b-cRE_aA_bCo_c, where RE is a rare-earth element always including La, A is either Si or Al, 6 at %≦a≦11 at %, 8 at %≦b≦18 at %, and 0 at %≦c≦9 at %, and has either a two phase structure consisting essentially of an α-Fe phase and an (RE, Fe, A) phase including 30 at % to 90 at % of RE or a three phase structure consisting essentially of the α-Fe phase, the (RE, Fe, A) phase including 30 at % to 90 at % of RE and an RE(Fe, A)₁₃ compound phase with an NaZn₁₃-type crystal structure. The respective phases have an average minor-axis size of 40 nm to 2 μm.

The invention relates to a modular charging/discharging system of a power battery pack of a multifunctional electromobile, which aims to provide a system which can effectively meet the requirement for the bi-directional power transmission of a charging station and can exert the functions of peak clipping and valley filling as well as peak modulation and frequency modulation of a power grid. The technical scheme is as follows: the modular charging/discharging system of the power battery pack of the multifunctional electromobile comprises a charging-station monitoring system and an information management system, wherein the charging-station monitoring system is composed of a computer and a network communication system. The modular charging/discharging system is characterized by also comprising a three-phase step-down transformer, wherein the high voltage side of the three-phase step-down transformer is connected with a power grid, and the low voltage side of the three-phase step-down transformer is connected in parallel with a plurality of charging/discharging branches; each branch comprises a three-phase distribution transformer and a charging/discharging module, and the three-phase distribution transformer is connected in series with the charging/discharging module; and each charging/discharging module comprises a pulse-width modulation alternating current/direct current (PWM AC/DC) converter with the function of bi-directional power transmission, a plurality of electromagnetic isolation type DC/DC transform modules with the function of bi-directional power transmission and the information management system, and the electromagnetic isolation type DC/DC transform modules are connected in parallel.

A synchronized control method for a three-phase three-level boost-type rectifier with reduced input current ripple and balanced output voltages is disclosed. The proposed control allows simplifying the control circuit as much as possible without compromising the rectifier performance. In fact, besides simplicity, the control method featured synchronized command signals to de switching devices, minimized input current ripple, full controllability of the output voltage, dynamic balance of the output center point, constant switching frequency, simplified design of EMC filters, good transient and steady state performance, and low cost. The invention described first the most important configurations that the three-phase three-level boost-type rectifier may assume and studied the converter's operation. The concept involved for output voltage, input current, neutral point balance and control system design was presented.

A method and system for detecting and locating a single-phase ground fault on a low current grounded power-distribution network, comprising: respectively testing and picking up the voltage signals and current signals at multiple positions on each phase feeder (61), and determining the corresponding transient voltage signals and transient current signals according to the extraction of the voltage signals and the current signals (62); when the change in the transient voltage signals and the transient current signals exceeds a preset threshold (63), synchronously picking up the voltage signals and current signals at multiple positions on a three-phase feeder (64); calculating corresponding zero-sequence voltages and zero-sequence currents according to the voltage signals and current signals synchronously picked up at multiple positions on the three-phase feeder (65), and then extracting the steady-state signal and transient signal of the zero-sequence voltage and zero-sequence current at each position on the three-phase feeder (66); and determining a specific fault location on a faulty line according to the steady-state signal and the transient signal (67). The method effectively detects and displays a single-phase ground fault on a low current grounded power-distribution network.

A polyphase electrosurgical system and method are provided. In embodiments, a radiofrequency generator having the capability of delivering a plurality of independent electrosurgical signals is disclosed. An electrosurgical instrument having an array of electrodes that correspond to the plurality of signals may be used to deliver the electrosurgical signals to tissue. In embodiments, three RF signals having a phase offset of about 120° therebetween, i.e., a three-phase configuration, may be used to achieve a balanced delivery of electrosurgical energy, which may lead to increased rates of energy delivery, improved control of tissue ablation regions, and improved operative outcomes. The phase, amplitude, and/or frequency of each signal may be independently variable in response to user inputs and/or biological parameters such as tissue impedance or return electrode current.

The invention relates to a super capacitor energy storage type power quality compensator. A system structure comprises a compensation transformer, a series compensator, a parallel compensator, a super capacitor group, a current foldback circuit, a bidirectional DC/DC chopper circuit, a signal sampling circuit, a control circuit, a drive circuit, a human-computer interface and corresponding auxiliary circuits, which form a three-phase three-wire system topological structure. By utilizing the excellent characteristics of great power density, high charging and discharging speed and long cycle life of a super capacitor, the super capacitor energy storage type power quality compensator is matched with the DC/DC chopper circuit to form an energy storage control system which plays the roles of adjusting power and stabilizing the voltage of a direct current bus in work. The invention also has the functions of dynamic voltage recovery, active filter and reactive compensation and can ensure that a load can obtain rated sine voltage and the current of a grid is sine current with the same direction (unit power factor) with that of a voltage fundamental wave positive sequence active component, thereby comprehensively improving the quality of power. The invention has positive generalization and application value for both the public grid and users.

When finding a current on an AC side of an inverter by observing that on a DC side, a current that is not affected by pulsating components contained in the AC current must be detected. Timing of change of a gate signal for driving a switch element of a phase having an intermediate magnitude among three-phase voltage command signals to ON/OFF is used as a reference time point for DC bus current detection. DC bus currents sampled T1 before and T2 after the reference time point are designated as IDC1 and IDC2, respectively. A detected current value of a maximum voltage phase is computed by using IDC2 and IDC1 respectively in an increase period and a decrease period of a carrier signal alternately. A detected current value of a minimum voltage phase is computed by using IDC1 and IDC2 respectively in an increase period and a decrease period alternately.

A flow measuring system combines a density measuring device and a device for measuring the speed of sound (SOS) propagating through the fluid flow and/or for determining the gas volume fraction (GVF) of the flow. The GVF meter measures acoustic pressures propagating through the fluids to measure the speed of sound α_mix propagating through the fluid to calculate at least gas volume fraction of the fluid and/or SOS. In response to the measured density and gas volume fraction, a processing unit determines the density of non-gaseous component of an aerated fluid flow. For three phase fluid flows, the processing unit can determine the phase fraction of the non-gaseous components of the fluid flow. The gas volume fraction (GVF) meter may include a sensing device having a plurality of strain-based or pressure sensors spaced axially along the pipe for measuring the acoustic pressures propagating through the flow.