Abstract: One or more example embodiments provide systems and methods for using impedance separation and impedance shaping.

Abstract: A controller for individual sites of the microgrid controls loads, sources, the importing of power, and the exporting of power as a function of the energy storage at the site. A microgrid of such sites provides the benefits of improved energy storage without the need for real-time communication between sites.

Abstract: A controller for individual sites of the microgrid controls loads, sources, the importing of power, and the exporting of power as a function of the energy storage at the site. A microgrid of such sites provides the benefits of improved energy storage without the need for real-time communication between sites.

Abstract: A semiconductor switch includes four diodes, two transistors, and a capacitor. The capacitor includes a fourth terminal and a fifth terminal. An anode of a third diode is connected to a third terminal of a first transistor. A cathode of the third diode is connected to a first terminal of the first transistor and to an anode of a first diode. An anode of a fourth diode is connected to a third terminal of a second transistor. A cathode of the fourth diode is connected to a first terminal of the second transistor and to an anode of the second diode. A cathode of the first diode is connected to a cathode of the second diode and to the fourth terminal of the capacitor. An anode of the third diode is connected to the anode of the fourth diode and to the fifth terminal of the capacitor.

Abstract: A semiconductor switch includes four diodes, two transistors, and a capacitor. The capacitor includes a fourth terminal and a fifth terminal. An anode of a third diode is connected to a third terminal of a first transistor. A cathode of the third diode is connected to a first terminal of the first transistor and to an anode of a first diode. An anode of a fourth diode is connected to a third terminal of a second transistor. A cathode of the fourth diode is connected to a first terminal of the second transistor and to an anode of the second diode. A cathode of the first diode is connected to a cathode of the second diode and to the fourth terminal of the capacitor. An anode of the third diode is connected to the anode of the fourth diode and to the fifth terminal of the capacitor.

Abstract: Methods and apparatuses are described for generating a quick response (QR) grid that represents electronic data associated with a digital document. A server captures electronic data associated with a digital document, the electronic data comprising a plurality of key-value pairs. The server determines a total size of the electronic data and partitions the electronic data into two or more portions. The server generates a map of QR codes based upon the two or more portions of electronic data, each QR code in the map comprising a header, a footer, and a payload containing one of the two or more portions of electronic data. The server creates a QR grid using the map of QR codes. The server prints a physical document that corresponds to the digital document, the physical document including the created QR grid.

Abstract: A controller controls power between a source and a load with a link capacitor. (a) A switch vector is selected based on load and source values, a capacitor voltage value, and a switch state selection mode. The switch vector identifies an on or off configuration for load and source switches during a subcycle that allow or do not allow current flow between the link capacitor and the load switch or source switch. (b) The state of the load and source switches is controlled in the on configuration or in the off configuration based on the selected switch vector. (c) It is determined that it is time to select a next switch vector. (a) to (c) are repeated for each subcycle of the determined number of switching subcycles. At least one load switch and at least one source switch are simultaneously in the on configuration during at least one subcycle.

Abstract: A power converter provides a pyramidal structure of switches communicating between a capacitive divider at the base of the pyramid and a terminal at the top of the pyramid to provide a transformation of a relationship between current and voltage in power transferred between the capacitive divider and the terminal at the top of the pyramid while providing reduced electrical interference and electrical rate of change (dv/dt).

Abstract: A power converter provides a pyramidal structure of switches communicating between a capacitive divider at the base of the pyramid and a terminal at the top of the pyramid to provide a transformation of a relationship between current and voltage in power transferred between the capacitive divider and the terminal at the top of the pyramid while providing reduced electrical interference and electrical rate of change (dv/dt).

Abstract: A controller controls power between a source and a load with a link capacitor. (a) A switch vector is selected based on load and source values, a capacitor voltage value, and a switch state selection mode. The switch vector identifies an on or off configuration for load and source switches during a subcycle that allow or do not allow current flow between the link capacitor and the load switch or source switch. (b) The state of the load and source switches is controlled in the on configuration or in the off configuration based on the selected switch vector. (c) It is determined that it is time to select a next switch vector. (a) to (c) are repeated for each subcycle of the determined number of switching subcycles. At least one load switch and at least one source switch are simultaneously in the on configuration during at least one subcycle.

Abstract: A controller selects a first switch vector based on a current, voltage, or power of a multi-phase load or power source. The first switch vector identifies a first state for each of a plurality of half-bridges of a converter as on or as off during a first interval. A second switch vector is selected based on the current, voltage, or power of the multi-phase load or power source. The second switch vector identifies a second state for each of the half-bridges as on or as off during a second interval. The first interval is computed based on the selected first switch vector. The second interval is computed based on the selected second switch vector. Each of the plurality of half-bridges is controlled as on or as off during the first interval based on the selected first switch vector and during the second interval based on the selected second switch vector.

Abstract: A controller selects a first switch vector based on a current, voltage, or power of a multi-phase load or power source. The first switch vector identifies a first state for each of a plurality of half-bridges of a converter as on or as off during a first interval. A second switch vector is selected based on the current, voltage, or power of the multi-phase load or power source. The second switch vector identifies a second state for each of the half-bridges as on or as off during a second interval. The first interval is computed based on the selected first switch vector. The second interval is computed based on the selected second switch vector. Each of the plurality of half-bridges is controlled as on or as off during the first interval based on the selected first switch vector and during the second interval based on the selected second switch vector.

Abstract: A wind turbine 36 has a back-to-back AC/DC/AC power electronic converter chain in which the grid side converter 48 is connected in series with DFIG stator windings 64. The machine side converter 56 is fed from the rotor windings 54 of the DFIG 44. Series connection of the grid side converter 48 enables voltage sag ride-through capability via control of the stator flux. In the event of a grid voltage sag, the series converter allows for a controlled response in the stator flux and electromagnetic shaft torque, protects the machine side converter and enables continued power delivery to the grid.

Abstract: An apparatus and method for reducing EMI generated by a power conversion device, as well as a power conversion device employing such apparatus or method (and/or devices employing such a power conversion device) are disclosed. In at least some embodiments, the apparatus includes a hybrid filter for use in reducing EMI. The hybrid filter includes a passive filtering component, and an active filtering component coupled at least indirectly to the passive filtering component. The active filtering component includes a voltage controlled voltage source, and the hybrid filter operates to reduce a level of a common mode current, whereby the EMI generated due to the common mode current is reduced.

Abstract: An apparatus and method for reducing EMI generated by a power conversion device, as well as a power conversion device employing such apparatus or method (and/or devices employing such a power conversion device) are disclosed. In at least some embodiments, the apparatus includes a hybrid filter for use in reducing EMI. The hybrid filter includes a passive filtering component, and an active filtering component coupled at least indirectly to the passive filtering component. The active filtering component includes a voltage controlled voltage source, and the hybrid filter operates to reduce a level of a common mode current, whereby the EMI generated due to the common mode current is reduced.

Abstract: A wind turbine 36 has a back-to-back AC/DC/AC power electronic converter chain in which the grid side converter 48 is connected in series with DFIG stator windings 64. The machine side converter 56 is fed from the rotor windings 54 of the DFIG 44. Series connection of the grid side converter 48 enables voltage sag ride-through capability via control of the stator flux. In the event of a grid voltage sag, the series converter allows for a controlled response in the stator flux and electromagnetic shaft torque, protects the machine side converter and enables continued power delivery to the grid.

Abstract: A three-phase AC to AC frequency converter has a transformer with a three-phase input and n sets of three-phase secondary outputs, where n is three or more, the voltages at each set of secondary output terminals being one or more multiples of 360°/n out of phase with the voltages at the other sets of secondary output terminals. The sets of secondary output terminals are connected to three single pole, n throw switches, the poles of which are connected to the three output terminals of the frequency converter. Each switch may have n semiconductor switching devices, each connected to the common pole and separately connected to one of the output terminals in each of the sets of secondary output terminals.

Abstract: A special purpose custom power control apparatus outputs AC power having or more particular characteristics relative to the AC power input thereto. Duty ratio of operation of GTO devices is controlled to transform the input power to the output power having its particular characteristics. In one embodiment duty ratio variation is used to provide a continuously variable transformation ratio from input to output. In another embodiment, duty ratio variation is used for controlling relative amounts of power drawn from different input buses, thus permitting isolation of faults and redirecting power flow. Another embodiment uses variation of GTO duty ratio to provide a continuously variable phase shift for each phase of a multi-phase distribution line. In another embodiment, duty ratio is modulated inversely to a voltage balance and a buck converter has a transfer ratio which is directly proportional to the duty ratio, to eliminate voltage unbalance on the multi-phase input AC.

Abstract: PWM converters provide buck, boost, buck-boost, flyback, and Cuk configurons for three phase AC-AC power control. In an AC-DC embodiment, only a single power conversion circuit is used in a configuration including a pair of series connected gate turn off devices which are oppositely poled and oppositely timed, are connected directly to an AC input source, and provide an output to a high frequency isolating transformer. The transformer provides an output to a rectifier, which thus provides the DC output.

Abstract: A power converter integrates an input boost converter and an output forward converter into a single power stage utilizing only two active switches. AC input power is provided through a rectifier to an input inductor which supplies current to a main node. The diode is connected from a main node to a DC bus supply line and current is returned to the rectifier by DC bus return line. An energy storage capacitor and a series connected switching device and diode are connected across the DC bus lines. A second control switching device is connected from the main node to the DC bus return line. The primary of a high frequency transformer is connected between the main node and the junction between the first switching device and diode, and the secondary of the transformer is connected to an output circuit which includes a rectifier and an inductor and capacitor filter to provide a DC output voltage to a load.