7105 results about "Power inverter" patented technology

A soft start circuit generates a soft start voltage which changes over time when light emission of an EEFL is started. A pulse modulator receives a feedback voltage that corresponds to the output voltage of an inverter and the soft start voltage, and adjusts the duty ratio of a pulse signal PWM such that these two voltages match one another using a feedback operation. A striking control circuit monitors an error signal which is asserted when an abnormal state occurs. In a case in which the error signal has been asserted at a detection timing after the soft start voltage has reached a target voltage, the striking control circuit resets and restarts the soft start circuit. A driver controls the switching of the voltage at the primary coil of a transformer according to the pulse signal received from the pulse modulator.

A power system employs an outer voltage feedback loop and an inner current feedback loop to control a power converter, such as a DC to AC inverter for transferring electrical power between a power source, for example a photovoltaic array, and a load, for example a power grid. The outer loop accommodates variations in the output of the power source, for example accommodating anomalies in IV characteristics such as IV droop characteristic associated with photovoltaic cells. The outer loop may employ a first control regime or a second control regime, for example, dependent on whether a DC bus voltage or power is smaller than a value corresponding to measurement resolution or expected noise.

A system and method for DC to AC conversion in a power generating array. The system and method includes a number of inverters coupled to a group of solar panels. A group controller coordinates operation of the inverters for interleaved switching of the inverters. The group controller communicates via a local area network, a wireless network, or both, to coordinate operation with additional groups of inverters coupled in parallel with additional solar panels.

A shift register includes a first transistor supplying an output terminal with a clock signal input to a first clock terminal and a second transistor discharging the output terminal. Defining the gate node of the first transistor as a first node, and the gate node of the second transistor as a second node, the shift register includes an inverter circuit in which the first node serves as its input node and a capacitive element serves as a load, and a buffer circuit receiving the output from the inverter circuit and outputting a signal to the second node.

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.

The present invention provides a method and apparatus for generating electrical power from multiple vehicles powered by fuel cells while the vehicles are parked in a parking lot. A plurality of spaced-apart electrical receptacles are provided for receiving an electric cable for connection to a parked vehicle for electrically connecting the fuel cell in each of the parked vehicles to the plurality of electrical receptacles. An electric power grid is electrically connected to the plurality of electrical receptacles for transferring D.C. electrical power from the fuel cells in the parked vehicles to the electric power grid. At least one electric power collection station is electrically connected to the electric power grid for collecting at a common point the D.C. electric power in the electric power grid. In addition, at least one inverter is electrically connected to the electric power collection station for converting the D.C. electric power to A.C. electric power. Apparatus is provided for supplying the A.C. electric power to a load or a utility grid.

An apparatus for converting Direct Current (DC) to Alternating Current (AC), comprising a plurality of inverters, each inverter having a separate DC input adapted to be coupled to at least one solar cell defining an area of a solar panel.

The invention relates to an island network with at least one energy generator, using regenerative energy sources, whereby the energy generator is preferably a wind energy plant with a first synchronous generator, a DC link, at least one first power rectifier and a power inverter, a second synchronous generator and an internal combustion engine which may be coupled with the second synchronous generator. A fully controllable wind energy unit (10) and an electromagnetic coupling (34) between the second synchronous generator (32) and the internal combustion engine (30) are provided in order to establish an island network in which the internal combustion engine can be switched off completely, so long as the wind energy unit is generating enough power for all connected users with an efficiency which is as high as possible.

AC module, integrating a solar battery and an inverter, can easily be connected with other plural AC modules in parallel by way of cascade connections. However, when the number of AC modules connected is improvidently increased, the current flowing through the current path or connector of the AC module exceeds a rated current. In view of this, the current detector detects a current in the collective-power current path of the AC module, and when the detected current value exceeds a value set in the reference current setting circuit, the current detector stops the inverter.

A power conversion system includes a number of photovoltaic arrays, a number of inverters, a transformer, and processor. The processor is structured to control the number of inverters and operate the power conversion system to provide maximum efficiency of power conversion by the number of photovoltaic arrays, the number of inverters and the transformer, and to maximize power output from the number of photovoltaic arrays.

A heat sink or cooling case has a cooling channel and at least one opening formed to face part of the channel. A first seal is provided outside the at least one opening. A cooling case has a groove located outside the first seal. Holes are discretely formed in the groove and leads from the groove to an exterior of the cooling case. A second seal is provided outside the groove. A radiating plate constituting a circuit case is mounted on the heat sink by using a clamping device inn or outside the second seal.

A fuel cell system minimizes the power loss that may occur in a conduction passage during supply of electric power from a fuel cell to a load. A bypass connects between the input of a DC / DC converter and the output thereof, and therefore supplies power generated by the fuel cell to an inverter, bypassing the DC / DC converter. A changeover switch selectively changes the connection of the output of the fuel cell between the connection to the input of the DC / DC converter and the connection to the bypass. When the fuel cell is connected to the DC / DC converter, the power from the fuel cell is supplied to the inverter or a battery via the DC / DC converter. When the fuel cell is connected to the bypass, the power from the fuel cell is supplied to the inverter, bypassing the DC / DC converter. A cutoff switch disconnects the output of the battery from a connecting line. That is, the cutoff switch disconnects the battery from the inverter, the bypass and the like when turned off. When turned on, the cutoff switch 41 connects the battery to those components.

An electric power supply apparatus includes a distributed power generator such as a gas turbine generator and a power converter such as an inverter apparatus for converting electric power generated by the distributed power generator into AC electric power (alternating-current power) having a required frequency and a required voltage and supplying the AC electric power to a load. The electric power supply apparatus further includes a control unit having output voltage vs. output current characteristics for determining an output voltage corresponding to an output current of the power converter. The output voltage vs. output current characteristics has a first dropping characteristic for causing output electric power of the electric generator to be limited, between a first output current exceeding a power generation capability of the electric generator and a second output current exceeding a power converting capability of the power converter.

In a welding power supply for creating welding current in a succession of current pulses with a maximum current level and a trailing off state which current pulses passing through a series circuit including an inductor and electrode in welding relationship with a workpiece wherein the power supply has (a) an inverter stage with an input to be connected to a power source, a first terminal at a first electrical polarity when the inverter is on, a second terminal at a second electrical polarity when the inverter is on, and a control to generate an off signal to turn the inverter off and remove current from the terminals to shift said current pulse toward an off state; and, (b) a power switching stage including a transistor based switch having a conduction condition passing current from the first terminal upon creation of a first logic signal and a non-conduction condition blocking current upon creation of a second logic signal, the improvement comprising: a sensor for measuring the instantaneous value of the welding current, a comparator for producing a low current signal when the instantaneous current is at a selected value substantially below the maximum current level and a circuit or program for creating the second logic signal upon production of a low current signal after generation of an off signal whereby the transistor based switch is switched from the conduction condition to the non-conduction condition when the welding current is generally at the selected value.

A system and apparatus for generating power. In one embodiment, the apparatus comprises a power module for coupling to a DC power source via a DC bus, wherein the power module (i) converts a first power from the DC power source to a second power, and (ii) comprises a maximum power point tracking module unit for dynamically adjusting a load voltage of the DC power source; an AC bus; and a controller, physically separate from the power module and coupled to the power module via the AC bus, for operatively controlling the power module.

An integrated drive system assembly is provided that combines an electric motor, a power inverter assembly and a gearbox into a single, multi-piece enclosure. Combining these components into a single enclosure reduces weight, reduces drive system complexity, reduces system volume, simplifies assembly integration into an electric vehicle, reduces manufacturing cost, allows the flexible and lengthy electrical cables between the power inverter and the electric motor to be replaced with short, low loss, rigid bus bars, and simplifies component cooling by allowing the use of a common thermal management system. The common thermal management system includes a liquid coolant loop that is thermally coupled to the electric motor, the power inverter assembly and the gearbox.

The present invention provides a simplified method of controlling power among the various sources and loads in a power system. Power generating sources are each connected to a common DC bus through a converter. The converter selectively transfers energy to the DC bus at a maximum rate or at a reduced rate according to the level of the DC voltage present on the DC bus. At least one storage device is preferably connected to the common DC bus through a power regulator. The power regulator selectively transfers energy to or from the DC bus as a function of DC voltage level present on the DC bus. Further, an inverter may be provided to bidirectionally convert between the DC voltage and an AC voltage for connection to a customer load or the utility grid. Each power conversion device is independently controlled to provide a modular and simplified power control system.

A motor control device capable of suitably inhibiting the pulsating torque of an alternating-current motor is provided. The motor control device comprises an axis error inference machine (30) which infers an axis error based on a current value of an inverter, detected by a current sensor (2); a Fourier rectification machine (316a) which extracts an axis error vector from the time-base changes of the axis error; an integral control machine (316b) additionally provided with a circular amplitude limiter, which is used to calculate a correction current vector for offsetting the pulsating torque, wherein a circle with a set amplitude limiting value serving as the radius is used as the base for limiting the movement of the correction current vector, and the integral control machine (316b) additionally provided with the circular amplitude limiter performs the circular amplitude limiting for limiting the movement of the correction current vector so as to enable the deflection angle of the correction current vector to be close to the deflection angle of the axis error vector.

A system and method for combining power from DC power sources. Each power source is coupled to a converter. Each converter converts input power to output power by monitoring and maintaining the input power at a maximum power point. Substantially all input power is converted to the output power, and the controlling is performed by allowing output voltage of the converter to vary. The converters are coupled in series. An inverter is connected in parallel with the series connection of the converters and inverts a DC input to the inverter from the converters into an AC output. The inverter maintains the voltage at the inverter input at a desirable voltage by varying the amount of the series current drawn from the converters. The series current and the output power of the converters, determine the output voltage at each converter.

A power inverter system includes a DC to AC inverter configured to convert DC voltage from a DC power source to AC voltage. A DC link couples the DC power source and the inverter. An inverter pre-charger operates to pre-charge the inverter to achieve a desired DC link voltage prior to connecting the power inverter system to an AC power grid. A phased lock loop synchronizes the pre-charged inverter to the AC power grid prior to connecting the power inverter system to the AC power grid. The pre-charged inverter regulates the DC link voltage to about the minimum voltage level that allows control of AC grid currents via the inverter subsequent to connecting the power inverter system to the AC grid. The inverter operates in a maximum power point tracking control mode only subsequent to a first voltage transient caused by connecting the DC power source to energize the power inverter system.

The invention concerns an inverter for solar panels which includes at least two inverter inputs to each of which a group of solar panels can be connected, and an inverter output to which a network can be connected. The inverter includes an inverter element with a direct voltage input and an alternating voltage output which converts the direct voltage which is connected to its direct voltage input into alternating voltage and sends it to the inverter output, an electronic control system which monitors the direct voltage which is connected to the direct voltage input of the inverter element and the network voltage and / or the network frequency of the network which is connected to the inverter output, and a switching system which is electrically arrayed between one of the at least two inverter inputs and the direct voltage input of the inverter element, wherein the at least two inverter inputs of the inverter are connected in series with the direct voltage input of the inverter element. The electronic control system is designed so that it triggers the switching system to disconnect the at least one inverter input of the inverter from the direct voltage input of the inverter element if the voltage which is connected to the direct voltage input of the inverter element exceeds an upper threshold value and / or the network voltage and / or the network frequency of the network which is connected to the inverter output lies outside a previously specified normal voltage or normal frequency range.The invention furthermore concerns a process to control an inverter for solar panels.

The invention in the simplest form is an improved variable speed engine / generator set with an integrated power conditioning system and control method, used to generate high quality AC power with optimum fuel efficiency and reduced emissions. The variable speed generator control scheme allows for load adaptive speed control of engine and generator field. The transformerless power inverter topology and control method provides the necessary output frequency, voltage and / or current waveform regulation, harmonic distortion rejection, and provides for single phase, or unbalanced loading.

A device for converting power from a floating source of DC power to a dual direct current (DC) output, the device includes: positive and negative input terminals connectible to the floating source of DC power; and positive and negative, and ground output terminals connectible to the dual DC output that may feed an inverter. The inverter may be either a two or three level inverter. A charge storage device may be connected in parallel to, and charged from, the positive and negative input terminals. A resonant circuit may be also connected between the charge storage device and the dual DC output. The resonant circuit may include an inductor connected in series with a capacitor. The charge storage device may discharge through the resonant circuit by switching through to either the negative output terminal or the positive output terminal.

An inverter circuit allowing a single drive circuit to perform both tracking control for tracking resonance frequency fluctuations caused by load fluctuations, and power control, thereby reducing switching loss. An inverter drive circuit part obtains a phase difference between output current and output voltage directed to a load circuit connected to a midpoint of two arm circuits of the inverter circuit, and controls a phase of the driving signal directed to each semiconductor switch such that the phase difference becomes zero or a predetermined value, enabling an operating frequency of the inverter circuit part to track a resonance frequency of the load circuit, and enabling a current phase to be delayed with respect to a voltage phase, thereby achieving ZCS. Since the phase difference is used, an auxiliary circuit is not necessary for measuring a current value in proximity to the semiconductor switches.

The present invention provides a highly reliable electric power converter reduced in parasitic inductance.An electric power converter that includes a capacitor module which has a DC terminal, an inverter which coverts a direct current into an alternating current, and heat release fins which cool the inverter, is constructed so that: the inverter has a power module including a plurality of power semiconductor elements; the power module further has a metallic base, a dielectric substrate provided on one face of the metallic base, a power semiconductor element fixed to the dielectric substrate, and a DC terminal; the metallic base has the heat release fins on the other face; the DC terminal in the power module and the DC terminal in the capacitor module are each formed by stacking flat plate conductors via an insulator; the two positive and negative DC terminals have respective front ends bent in opposite directions; a plane including the bent sections is used as a surface for connecting the power module and the capacitor module; and the insulators overlap each other at the connection surface.

A control apparatus for a multi-phase rotary machine includes a control unit and a plurality of power supply systems including respective inverter units. When a short-circuiting failure occurs in one of the systems due to an ON-failure in any one of FETs in an inverter unit of the failure system, the control unit stops driving of the rotary machine by bringing all the FETs in the failure system into the OFF state. The control unit controls FETs of the non-failure system such that a brake torque generated in the failure system is cancelled or the influence of the brake torque exerted on the driving of the motor is reduced.

A power management system for a vehicle. The system may be flexibly configured using various arrangements of DC to AC inverters, DC to DC converters AC to DC converters, DC to AC converters and AC to AC converters, one or more batteries, and a control portion to provide an AC bus, a primary DC bus and a secondary DC bus. The control portion monitors the status of the buses, inverters and converters and controls the operation of the inverters and converters to supply and regulate the power supplied by the buses. The inverters and converters may be bidirectional, allowing power to be transferred between buses.