Abstract: A power converter module is disclosed, which is an all-digital module. The power converter module includes a reference voltage generation unit, a voltage loop control unit, a current loop control unit, an input voltage compensation unit, and a pulse width modulation generation unit, to transfer input power to stable output power for providing power to an external loading device through driving bridge switch unit with external driver. The voltage loop control unit and the current loop control unit contain a proportion-integral-differentiation controller for receiving signal related to voltage and current of loading device to form voltage control loop and current control loop. The pulse width modulation generation unit contains function of deciding necessary stop time to improve quality of output power and decrease the effect of input power and loading variation, and to provide stable sine-waveform output power to the external loading device.

Abstract: The invention relates to a method for operating an inverter comprising a step-up device which is upstream-connected by means of an intermediate circuit and is connectable to a direct-current source with a variable reference sampling current wherein said inverter and the step-up device are provided with an efficiency optimizing working area, respectively. When the variable reference sampling current is raised and the step-up device approaches a pulse duty factor value, the intermediate circuit voltage is reduced and the variable reference sampling current is stabilized, said intermediate circuit voltage is re-raised. When the direct-current source is in a permanent operational state, the inverter and the step-up device operate in the efficiency optimizing working area thereof, respectively.

Abstract: A controller calculates a total power fluctuation including a power fluctuation on a first unit and a power fluctuation on a second unit. The controller estimate a voltage fluctuation of the system voltage based on the total power fluctuation. Then, the controller calculates a control amount for a voltage converter by reflecting the estimated voltage fluctuation. The estimated voltage fluctuation can be used to correct a feed-forward control amount. As a result, a voltage stabilizing control is performed based on the estimated voltage fluctuation which could be occurred in response to the total power fluctuation if no stabilizing control is performed. Thereby, the stability of the system voltage can be improved without using a large size smoothing capacitor.

Abstract: Method and apparatus for monitoring, measuring and recording the operating values of each of a plurality of inter-connected AC PV modules and performing a diagnostic analysis, including comparing the those operating values to each other and to operating values recorded at an earlier time to determine laminate degradation and the performance-attenuating effect of temperature, soiling, shading, and snow cover on the modules.

Abstract: An isolated power converter comprising a transformer arranged in such a way that the mirrored primary voltage on the secondary side has a positive potential relative to ground, said converter comprising a derivating net arranged to cause the second transistor to conduct in dependence of the voltage across the secondary winding, the source of the second transistor being connected to the negative end of the secondary winding, the drain of a third transistor further being connected to the positive end of the secondary winding, a second capacitor and a second resistor being connected between the gate and the source of the third transistor, a third resistor connected between the second resistor and the drain of the second transistor, a third capacitor connected between the sources of the second and third transistors to provide a first output voltage on one terminal of the third capacitor and a second output voltage on the other terminal of the third capacitor.

Abstract: Systems and methods are provided for detecting a resonance on a bus coupled to an inverter module. A method involves generating a first signal on the bus with a first frequency and sweeping the first signal from the first frequency to a second frequency. A second signal, which may be influenced by a characteristic of a component coupled to the bus, is obtained from the bus during the sweep of the first signal from the first frequency to the second frequency. The method further involves determining a resonant frequency based on the first signal and the second signal and updating the inverter module such that the resonant frequency is not used as a switching frequency for the inverter module.

Abstract: Systems and methods are provided for delivering current using a matrix converter in a vehicle. An electrical system comprises an AC interface, a first conversion module coupled to the AC interface, an inductive element coupled between the AC interface and the first conversion module, and a control module coupled to the first conversion module. The control module is configured to operate the first conversion module in a bidirectional operating mode to commutate current bidirectionally. When a magnitude of the current through the inductive element is greater than a first threshold value, the control module operates the conversion module in a unidirectional operating mode, wherein current is commutated unidirectionally.

Abstract: The invention concerns a method of controlling an inverter device, a control device as well as an inverter device and a direct current power transmission system. The direct current power transmission system is provided for connection to an AC voltage bus of an AC power system and comprises the control device and the inverter device that converts between DC power and AC power. The control device receives measurements of the voltage (VAC) at the AC voltage bus and controls the inverter device to provide a constant AC voltage on the bus.

Abstract: A method for providing a maximum power point tracking (MPPT) process for an energy generating device is provided. The method includes coupling a local converter to the energy generating device. A determination is made regarding whether the local converter is operating at or below a maximum acceptable temperature. A determination is made regarding whether at least one current associated with the local converter is acceptable. When the local converter is determined to be operating at or below the maximum acceptable temperature and when the at least one current associated with the local converter is determined to be acceptable, the MPPT process is enabled within the local converter.

Abstract: A distributed power supply system is configured to execute a process for determining whether or not to permit a diagnostic process in such a manner that it is determined whether or not a difference between a set upper limit value and an actual measurement current value is not less than a load current value, the set upper limit value being a predetermined upper limit value set with respect to a detected current of a current sensor, the measurement current value being detected by the current sensor in a state where the diagnostic process is not executed, and the load current value being a value of a current flowing from a commercial power utility to a power load during execution of the diagnostic process; and if it is determined that the difference is not less than the load current value, the controller permits the diagnostic process.

Abstract: The Scalable and Redundant Mini-inverters as described in this invention include double, triple, or quadruple redundant capabilities so that the Mini-inverters can work in a harsh environment for a prolonged period of time. A number of regular, redundant, triple redundant, or quadruple redundant Mini-inverters with one, two, three, or multiple input channels in a mixed variety can easily connect to one, two, three, or multiple DC power sources such as solar PV modules, invert the DC power to AC power, and daisy chain together to generate AC power to the power grid.

Abstract: A backlight driving system comprises a first inverter circuit, a second inverter circuit, a pulse width modulation (PWM) controller, a frequency regulator and a switch circuit. The pulse width modulation (PWM) controller generates an illumination signal to control the first and second inverter circuits to illuminate first and second backlight units in response to a first enable signal, and generates a maintaining signal to control the first and second inverter circuits to maintain stable lighting of the first and second backlight units in response to a first feedback signal. The frequency regulator controls the PWM controller to generate the illumination signal and the maintaining signal in response to a second enable signal and a second feedback signal, respectively. The switch circuit connects the PWM controller to the second inverter circuit in response to the second enable signal.

Abstract: A converter unit configured to couple to a photovoltaic panel (PV) may include a controller to sense an output voltage and output current produced by the photovoltaic panel, and manage the output voltage of a corresponding power converter coupled to a DC bus to regulate the resultant bus voltage to a point that reduces overall system losses, and removes non-idealities when the panels are series connected. The controller may also adapt to output condition constraints, and perform a combination of input voltage and output voltage management and regulation, including maximum power point tracking (MPPT) for the PV. The output voltage and output current characteristic of the power converter may be shaped to present a power gradient—which may be hysteretically controlled—to the DC bus to compel an inverter coupled to the DC bus to perform its own MPPT to hold the DC-bus voltage within a determinate desired operating range.

Abstract: A power distribution system includes a DC-DC converter which outputs a DC power after converting the DC power outputted from a DC power source to a desired voltage level. In the power distribution system, the DC-DC converter is controlled so as to operate only when the input voltage falls in a predetermined range.

Abstract: Embodiments of the invention can provide systems, methods, and apparatus for operating a power converter. According to one embodiment, a system for operating a power converter can be provided. The system can include a direct current (DC) power source with an output electrically coupled to an input of the power converter. The system can also include a controller operable to modify the performance of the DC power source through the power converter. As part of this modification, the controller can determine whether a low voltage ride (LVRT) event exists in a load and can adjust the DC power source when a LVRT event occurs.

Abstract: Described is a method for operating a converter for a system for generating electrical energy. In an embodiment of the method, the output voltage of the converter is converted to a d, q coordinate system, wherein the d, q coordinate system is assigned to the frequency of the voltage for the energy supply grid. A desired value is furthermore specified in the d, q coordinate system, several momentary or future values are determined from the output voltage in the d, q coordinate system for different switch positions of the converter, deviations between the desired value and the momentary or future values are determined in the d, q coordinate system, and the converter is switched to one of the switch positions in dependence on these deviations.

Abstract: The present invention discloses a power conversion circuit. A control module controls a pulse width modulation regulator to regulate a duty cycle of a DC-DC converter according to the direct current link voltage of the DC-DC converter and the output current and voltage of a renewable power supply. The control module also controls the pulse width modulation regulator to regulate a duty cycle of a DC-AC inverter according to the direct current link voltage of the DC-DC converter, output voltage of a utility power supply, and the output current and voltage of the renewable power supply.

Abstract: A solid state relay has independent charge pumps isolating each gate of a full bridge to achieve faster and proper gate turn on. The low side MOSFETs of the bridge are the current sensing device reducing loss and allowing a device controlled by the relay to achieve peak performance. Dynamic braking is achieved by the two low side MOSFETs being fully conducted and applying a load across the DC motor. Addition of a microprocessor to the device provides undervoltage sensing, current vs time readings, motor stall sensing, and motor temperature sensing. Motor temperature is detected by checking impedance of the motor at microsecond pulses to see if the motor is getting hot.

Abstract: An electric power conversion device includes a power conversion circuit for receiving electric power from an overhead wire through an LC filter circuit composed of a reactor and a capacitor and converting the electric power to output and a control unit for controlling the power conversion circuit, wherein the control unit is provided with a delay unit for delaying the voltage across the capacitor so as to produce a first control signal, produces a second output voltage instruction from the first control signal and a first output voltage instruction specifying the magnitude of the output voltage of the converted power, and controls the power conversion circuit based on the second output voltage instruction.

Abstract: A method for operating a converter circuit is provided. The converter circuit includes a converter unit and a transformer. The transformer includes at least one winding set with a primary winding and a secondary winding. The converter unit is connected, on the AC voltage side, to the primary winding of the respective winding set. In order to compensate for undesirable saturation of the transformer, the converter unit is used to deliberately apply a DC voltage to the primary winding of the respective winding set of the transformer.

Abstract: An electric machine drive system is described. The system includes an inverter, an electric machine coupled to the inverter by at least one output conductor and including a ground connection, and an active common mode current reducing device coupled between the ground connection of the electric machine and the inverter.

Abstract: The present invention proposes a circuit for converting DC into AC pulsed voltage. The circuit comprises two or four controllable semiconductor switches as well as a corresponding controller unit. The controller unit controls the opening and closing of the two or four controllable semiconductor switches using a preset control mode. When the circuit is used as the driver circuit of a capacitive load such as a DBD lamp, the luminous efficiency of the DBD lamp is improved.

Abstract: A synchronous operating system for operating a plurality of discharge tube lighting apparatuses at the same frequency and same phase includes (1) an oscillator of a triangular wave signal whose inclination for charging a capacitor C2 and inclination for discharging the same are the same, (2) a signal generation part to generate, in a period shorter than a half period of the triangular wave signal, a first drive signal having a pulse width corresponding to a load current, and (3) a signal generation part of a second drive signal having a pulse width substantially equal to that of the first drive signal and a phase difference of about 180 degrees with respect to the same.

Abstract: A power system includes a plurality of DC/DC converters and a DC/AC inverter. The plurality of DC/DC converters having outputs electrically connected in parallel for supplying a DC voltage bus to an input of the DC/AC inverter. The plurality of DC/DC converters each include a maximum power point tracker (MPPT). Various DC/DC converters and DC/AC inverters suitable for use in this system and others are also disclosed.

Abstract: Control systems, methods and power conversion systems are presented for reducing common mode voltages in AC motor loads driven by inverter PWM control using switching sequences with only active vectors where a first vector of each switching sequence differs by one phase switching state from a last vector of a switching sequence of an adjacent sector, along with enhanced deadtime compensation and reflected wave reduction techniques in providing pulse width modulated switching signals to a switching inverter.

Abstract: A control circuit controls a power output module and drives a load device. The control circuit includes a conversion unit, a feed-forward unit, a feedback unit and a control unit. The conversion unit generates a driving signal according to an output signal of the power output module for driving the load device. The feed-forward unit generates a duty cycle reference signal according to the output signal. The feedback unit generates a feedback signal according to the driving signal. The control unit outputs a control signal to control the conversion unit according to the duty cycle reference signal and feedback signal, thereby limiting the output power of the power output module within the maximum power region. A tracking method of the maximum power is also disclosed.

Abstract: An uninterruptible power supply (UPS) system has an inverter having an output coupled to a primary side of an output transformer. The UPS system has a controller having a dual gain voltage regulator for controlling the output voltage of the inverter of a UPS system that uses active and reactive current components of a load current flowing out an output of the UPS system.

Abstract: A control unit of an electric power converter, which is used in a three-phase motor having two winding wire systems, performs for a first duty instruction signal regarding a voltage applied to a first winding wire group a flatbed two-phase modulation process, and performs for a second duty instruction signal regarding a voltage applied to a second winding wire group a flattop two-phase modulation process. By phase-shifting the second duty instruction signal by 30° from the first duty instruction signal, a timing of maximum value of the first duty instruction signal is shifted from a timing of minimum value of the second duty instruction signal. Even when the maximum value is greater than a center output value and the minimum value is smaller than the center output value, overlapping of capacitor discharge is avoided, thereby reducing a ripple electric current.

Abstract: A multi-stage power supply uses a boost stage and an inverter stage to boost the voltage value of a DC power supply to a desired level, and then convert the power into an AC form. The multi-stage power supply additionally has a controller which can simultaneously control the boost stage and the inverter stage using counter-synchronous signals.

Abstract: The present invention relates to a transformerless photovoltaic grid-connecting inverting device and an inverting control method thereof. The inverting device comprising a boosting unit, an inverting unit, a grid-connecting unit and a control unit. The boosting unit is connected to a solar cell, for boosting an output voltage of the solar cell and then outputting a direct voltage. The inverting unit is used to convert the direct voltage output by the boosting unit into an alternating voltage. The grid-connecting unit is connected between the inverting unit and an alternating power grid, and closes or breaks up the electrical connection between the inverting unit and the alternating power grid based on a control signal.

Abstract: The present invention provides a startup sequence control method of fuel cell-super capacitor hybrid electric vehicles, which can protect a fuel cell at the time of the starting of the fuel cell, reduce the start-up time and promote convenience of a driver in a fuel cell-super capacitor serial hybrid system which does not employ a high-voltage power converter.

Abstract: A method of connecting a photovoltaic device to an AC power grid through an inverter includes monitoring a DC voltage at an input of an inverter, and activating the inverter when the monitored DC voltage exceeds a first predetermined threshold. The method further includes synchronizing an output voltage of the inverter with a grid voltage, connecting an output of the inverter to the AC power grid upon synchronization if the monitored DC voltage exceeds a second predetermined threshold, and deactivating the inverter if a detected power being fed through the inverter falls below a predetermined power threshold while maintaining the connection between the output of the inverter and the AC power grid. Lastly, the method includes disconnecting the output of the deactivated inverter from the grid if the monitored DC voltage falls below a third predetermined threshold. Further, an apparatus that performs such functionality is also provided.

Abstract: In a general aspect, a power conversion system includes a power converter, a transformer, and a voltage adjustment device. The power converter is configured to receive a variable DC power generated by a power generation device and to convert the received DC power to AC power at a first voltage. The transformer is configured to receive the AC power from the power converter and to deliver AC power at a second voltage to a utility power network. The voltage adjustment device is configured to adjust the first voltage to a target value determined on the basis of a voltage of the DC power.

Abstract: A fuel cell system FCS includes a fuel cell FC, a motor ES4 connected to the fuel cell FC, an FC boost converter ES6 which raises the output voltage of the fuel cell FC to output the voltage to the motor ES4, an inverter ES3, a current sensor S2, and a controller EC which controls the fuel cell FC, the FC boost converter ES6 and the inverter ES3. The controller EC controls the inverter ES3 so as to raise the target output voltage of the inverter, when the current detected by the current sensor S2 exceeds a predetermined current threshold value.

Abstract: A biased current-limit circuit for limiting a maximum output power of a power converter includes an oscillator for generating a pulse signal and an oscillation signal. A waveform generator generates a waveform signal in response to the oscillation signal. A sample-hold circuit is used to sample the waveform signal to generate a hold signal in response to a switching signal. The sample-hold circuit further samples the hold signal to generate a current-limit threshold in response to a second-sampling signal. A current comparator is utilized to compare a current-sensing signal with the current-limit threshold to limit a maximum on-time of the switching signal.

Abstract: A compensation circuit and a compensation method for providing compensation of a power converter are proposed. A current sense circuit is coupled to receive a switching current for generating a current signal. A signal generation circuit is developed to generate a first compensation signal and a second compensation signal for adjusting the current signal. The first compensation signal is coupled to adjust the current signal for the output power limit of the power converter. The second compensation signal is coupled to adjust the current signal for the slope compensation. The slope of the first compensation signal is decreased when the power transistor is turned on. The slope of the second compensation signal is increased in response to the turn on of the power transistor.

Abstract: An electrical power generation system, such as a solar power inverter, can provide dynamic real-time power compensation, so as to mitigate the effects of voltage sags and swells (e.g., on a utility grid) and thereby provide voltage support functionality to a local grid. The electrical power generation system can do so by receiving first synchrophasor measurements that are taken at a point on the utility grid and transmitted to the electrical power generation system and by taking second synchrophasor measurements. The first and second synchrophasors indicate voltage magnitude and frequency of the alternating current (AC) at their respective measurement points. The electrical power generation system can compare the first synchrophasors with the second synchrophasors and based upon the comparison, vary the power factor of the power the electrical power generation system generates (e.g., by either supplying or absorbing reactive power).

Abstract: A switching control circuit for a switching power converter is provided. The switching control circuit is coupled to a switching device and an auxiliary winding of a transformer. The switching control circuit includes a valley detecting circuit, a valley lock circuit, and a PWM circuit. The valley detecting circuit is coupled to receive a reflected voltage signal from the auxiliary winding of the transformer for outputting a control signal in response to the reflected voltage signal. The valley lock circuit is coupled to receive the control signal for outputting a judging signal in response to the control signal during a first period and a second period following the first period. The PWM circuit outputs a switching signal in response to the judging signal.

Abstract: A method and apparatus for power conversion. In one embodiment, the apparatus comprises a DC-AC conversion stage; an intermediate capacitor coupled across the DC-AC conversion stage; and a burst mode controller coupled to the intermediate capacitor and the DC-AC conversion stage, wherein the burst mode controller (i) maintains a voltage of the intermediate capacitor below a preset limit during a storage period and (ii) drives the DC-AC conversion stage to convert DC input to AC output during a burst period, wherein the storage and burst periods occur during a burst mode operation.

Abstract: In a power conversion device that includes a PWM converting means for generating a PWM pulse by comparing three-phase voltage commands with a triangular wave carrier signal, a power converter for converting between a DC voltage and a three-phase AC voltage by driving a switching element according to the PWM pulse, a current detecting means for detecting a pulsed current flowing through a DC bus conductor of a main circuit, and a voltage command correcting means for correcting three-phase voltage commands, which corrects the three-phase voltage commands so that a line voltage value between the maximum phase and an intermediate phase and a line voltage value between the intermediate phase and the minimum phase are each equal to or larger than a predetermined value, the maximum phase, intermediate phase, and minimum phase being determined in correspondence to momentary values of the three-phase voltage commands arranged in descending order, if the voltage command is outside an allowable upper limit or lower limi

Abstract: 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.

Abstract: A power conversion device includes a power switching circuit that has a plurality of series circuits in each of which a switching element that operates as an upper arm and a switching element that operates as a lower arm are connected in series, and a control circuit that generates control signals for controlling the continuity or discontinuity of the switching elements, and, if the relationship between the state of a switching element in a control cycle and the state of the switching element in the next control cycle is a discontinuous relationship, that additionally performs control to make the switching element continuous or discontinuous on the basis of the state of the switching element in the control cycle and the state of the switching element in the next control cycle.

Abstract: A biased current-limit circuit for limiting a maximum output power of a power converter includes an oscillator for generating a pulse signal. A waveform generator generates a waveform signal in response to a switching signal and a second-sampling signal. A sample-hold circuit is used to sample the waveform signal to generate a hold signal in response to a first-sampling signal. The sample-hold circuit further samples the hold signal to generate a current-limit threshold in response to the second-sampling signal. A current comparator is utilized to compare a current-sensing signal with the current-limit threshold to limit a maximum on-time of the switching signal.

Abstract: A detected DC voltage value estimation mechanism samples detected DC voltage values at specific intervals of a period T, stores detected DC voltage values Vn to Vn?m detected at a present time tn up to a sampling time tn?m which is m sampling cycles (m?1) before the present time tn, and calculates a DC voltage estimation value Vn+1 at a next time tn+1 using the detected DC voltage values Vn to Vn?m, expressing a curve connecting the voltage values Vn to Vn?m by a specific function. An output voltage control into which the DC voltage estimation value Vn+1 is input corrects an output voltage command value and outputs the corrected output voltage command value to a power converter.

Abstract: 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.

Abstract: A power converter system includes a power converter system including: a DC-to-AC power converter; a first output configured to be coupled to a power grid; a first input configured to be coupled to the power grid; second outputs each configured to be coupled to a corresponding AC load; a power-grid switch coupled to the converter and to the first output; load switches coupled to the converter, the second outputs, and the first input; and a controller coupled to the load switches and to the first output and configured to determine whether energy from the power grid satisfies at least one criterion, the controller being further configured to control the power-grid switch and the load switches to couple the converter to the first output and to couple the first input to the second outputs if the at least one criterion is satisfied and otherwise to control the power-grid switch and the load switches to isolate the converter from the first output and to couple the converter to at least one of the second outputs.

Abstract: An isolating circuit for a DC/AC converter includes an input, an output, an energy storage element and a switch element. The DC/AC converter includes an energy storage isolated from mains during a freewheeling phase. The output of the isolating circuit is configured to be connected to the DC/AC converter, and the energy storage element is connected to the input and serves for storing energy received from the input. The switching element is connected between the energy storage element and the output of the isolating circuit and is operative to connect the energy storage element to the output during the freewheeling phase, and to isolate the energy storage element from the output outside the freewheeling phase of the DC/AC converter.

Abstract: Switching Converter with a novel two-loop Integrated magnetic structure integrates transformer and two output inductors and eliminates large circulating current in the transformer secondary side resulting in ultra high efficiency and zero ripple output current as well as zero ripple currents in both output inductors simultaneously. The novel lossless switching method eliminates the primary side switching losses to result in switching converter with highest efficiency, compact size and additional performance advantages, such as ultra low output ripple voltage, low EMI noise and improved reliability with additional benefits when operated with a front-end Power Factor Converter for computer server applications.

Abstract: The present invention discloses a charger control circuit and a charger control method for controlling a charger having a transformer, the transformer including a primary winding and a secondary winding. The charger control circuit comprises: a power switch coupled to the primary winding; a switch control circuit controlling the operation of the power switch; and a detection circuit which generates a signal according to a voltage at a node between the power switch and the primary winding, and supplies the signal to the switch control circuit.

Abstract: A method to convert direct current (DC) power generated by a photovoltaic (PV) arrays to alternating current (AC) power using a PV inverter, the method includes: applying the DC power generated the PV array to the PV inverter; boosting the DC power from the PV array from a predetermined voltage level to a predetermine DC link voltage, wherein the PV array is regulated by the boosting to output a voltage at the predetermined voltage level; converting the boosted DC power to AC power, and disabling the boost of the power generated by the PV array after the array has a predetermined voltage level at least as great as the DC link voltage.