Abstract: There are provided methods and systems for interfacing converters and solar power arrays. For example, there is provided a method for interfacing a solar power generation apparatus with an electricity grid. The method can include connecting a first level and a second level of the solar power generation apparatus to a two-level converter. Furthermore, the method can include interfacing the two-level converter with the electricity grid via a four-wire connection.

Abstract: There are provided methods and systems for operating insulated gate bipolar transistors (IGBTs). For example, there is provided a method that can include detecting a desaturation condition in an IGBT and initiating a turn off procedure when desaturation is detected. The turn off procedure can include holding a gate of the IGBT at at least one voltage level intermediate between a positive rail voltage and a negative rail voltage of an operational range of the IGBT.

Abstract: Provided is a method for controlling operation of semiconductor gates in a power conversion system including one or more multilevel inverters coupleable to a modulator and a controller. The method includes generating, via the controller, a control signal responsive to an output current power factor associated with the inverters and producing a discontinuous pulse width modulation reference signal based upon the control signal and a target output power, the discontinuous pulse width modulation reference signal being indicative of shifting a phase angle between current and voltage. A gating signal is generated for output from the modulator, as a function of the reference signal and a carrier waveform. The gating signal adjusts the phase angle to prevent switching of the semiconductor gates.

Abstract: Provided is a fault isolation apparatus for an inverter configured for coupling to an external power supply. The apparatus includes a plurality of fault detection devices, each configured to (i) complete an electrical path between the inverter and the external power supply and (ii) detect a fault along its respective electrical path. The apparatus also includes a controller configured to instruct the fault detection device to complete its respective electrical path only when the path is devoid of the detected fault.

Abstract: A compact stacked power module including a positive direct-current-bus-voltage plate having a positive-plate surface and a negative direct-current-bus-voltage plate having a negative-plate surface. The compact stacked power module also includes an alternating-current output plate having opposing first and second output-plate surfaces, a first semiconductor switch contacting the negative-plate surface and the first output-plate surface, and a second semiconductor switch contacting the positive-plate surface and the second output-plate surface. The compact stacked power module further includes a capacitor contacting the negative-plate surface and the positive-plate surface, wherein the capacitor is electrically in parallel with the first and second semiconductor switches.

Abstract: A compact stacked power module including a positive direct-current-bus-voltage plate having a positive-plate surface and a negative direct-current-bus-voltage plate having a negative-plate surface. The compact stacked power module also includes an alternating-current output plate having opposing first and second output-plate surfaces, a first semiconductor switch contacting the negative-plate surface and the first output-plate surface, and a second semiconductor switch contacting the positive-plate surface and the second output-plate surface. The compact stacked power module further includes a capacitor contacting the negative-plate surface and the positive-plate surface, wherein the capacitor is electrically in parallel with the first and second semiconductor switches.

Abstract: A method for detecting a grid event is provided. The method includes sampling grid voltage and grid current over a fixed period of time; determining grid impedance at one or more frequencies using the sampled grid voltage and the sampled grid current; comparing the grid impedance at the one or more frequencies to a known expected grid impedance at the one or more frequencies; and detecting a grid event based on the comparison.

Abstract: Provided is a method for controlling operation of semiconductor gates in a power conversion system including one or more multilevel inverters coupleable to a modulator and a controller. The method includes generating, via the controller, a control signal responsive to an output current power factor associated with the inverters and producing a discontinuous pulse width modulation reference signal based upon the control signal and a target output power, the discontinuous pulse width modulation reference signal being indicative of shifting a phase angle between current and voltage. A gating signal is generated for output from the modulator, as a function of the reference signal and a carrier waveform. The gating signal adjusts the phase angle to prevent switching of the semiconductor gates.

Abstract: Provided is system including a temperature regulator including at least on regulation component in communication with a semiconductor within a converter, and a peak detector in communication with the semiconductor within the converter configured to identify a maximum temperature of each semiconductor. Also provided is a method for regulating temperature change of semiconductor components including measuring a semiconductor temperature, determining a reference temperature when the semiconductor is energized, summing the first semiconductor temperature and the reference temperature to generate a first temperature sum, comparing the first temperature sum to a coolant temperature to generate a first temperature difference. The method also circulates a fluid configured within the system such that the first temperature difference is adjusted.

Abstract: Systems and methods of determining bond wire failures are provided. In particular, data indicative of a first resistance of a first bond wire set associated with a first semiconductor device on a power semiconductor module can be obtained. In addition, data indicative of a second resistance of a second bond wire set associated with a second semiconductor device on the power semiconductor module can be obtained. A bond wire failure can then be determined in the first bond wire set or the second bond wire set based at least in part on the data indicative of the first resistance of the first bond wire set and the data indicative of the second resistance of the second bond wire set.

Abstract: Systems and methods for controlling the state of charge of an energy storage system used in conjunction with a renewable energy source or other power generation system are provided. More particularly, a future output requirement of the energy storage system can be predicted based at least in part on data indicative of anticipated conditions, such as weather conditions, wake conditions, or other suitable conditions. A control system can adjust a state of charge setpoint from a nominal setpoint (e.g. 50%) to an adjusted setpoint based at least in part on the future output requirement. In this way, the energy storage system can better accommodate the output requirements of the energy storage system during varying weather conditions.

Abstract: The present subject matter is directed to systems and methods for controlling variable speed generators, particularly converters associated with doubly-fed induction generators (DFIG) to permit use of harmonic attenuating filters that are generally smaller and less costly than previous similar filters. The subject matter provides for controlling line-side and rotor-side converters in such a manner that the frequencies generated by the converters are interleaved in a manner that the filters see a higher switching frequency and thus may be designed based on those higher frequencies, thereby requiring smaller and less expensive components.

Abstract: A method for controlling a power generation system connected to a weak grid may generally include operating a power converter of the system so as to produce current at or above a power factor threshold associated with a power factor operating requirement for the system, detecting that a generator speed of the system has increased over a period of time, detecting that a local reference voltage for the system has decreased within the same period of time over which the generator speed has increased and adjusting the operation of the power converter to produce current at a reduced power factor below the power factor threshold so as to increase a real power output of the system.

Abstract: A gate drive circuit for applying a voltage to a gate of a semiconductor switching device is disclosed. The gate drive circuit includes a gate drive controller that provides voltage commands for operating the semiconductor switching device, a plurality of primary gate resistors coupled between the gate drive controller and the semiconductor switching device, one or more secondary gate resistors connected in parallel with the primary gate resistors, a primary transistor connected in series with each of the primary gate resistors, and a secondary transistor connected in series with each of the secondary gate resistors. Further, one of the primary or secondary transistors receives the one or more voltage commands from the gate drive controller and provides one or more corresponding voltage levels to the semiconductor switching device via one of the primary or secondary gate resistors so as to control the on-off behavior of the semiconductor switching device.

Abstract: Provided is a system for regulating temperature change of semiconductor components within a converter. The system includes a temperature regulator in communication with at least one semiconductor within the converter and a power source, the temperature regulator comprising a controller. Also included is a peak detector in communication with at least one of the semiconductors and configured to identify a maximum temperature of each semiconductor when the semiconductor conducts high current.

Abstract: Provided is system including a temperature regulator including at least on regulation component in communication with a semiconductor within a converter, and a peak detector in communication with the semiconductor within the converter configured to identify a maximum temperature of each semiconductor. Also provided is a method for regulating temperature change of semiconductor components including measuring a semiconductor temperature, determining a reference temperature when the semiconductor is energized, summing the first semiconductor temperature and the reference temperature to generate a first temperature sum, comparing the first temperature sum to a coolant temperature to generate a first temperature difference. The method also circulates a fluid configured within the system such that the first temperature difference is adjusted.

Abstract: Renewable energy power systems, DC to DC converters, and methods for operating energy storage systems are provided. A system includes a power converter having a DC bus, and an energy storage system coupled to the DC bus of the power converter. The energy storage system includes an energy storage device and a switching power supply coupled between the energy storage device and the DC bus of the power converter. The switching power supply includes a plurality of switching elements, and an energy storage device protection circuit coupled between the plurality of switching elements and the energy storage device, the energy storage device protection circuit including a solid state switch. The switching power supply further includes a fuse coupled to the energy storage device protection circuit.

Abstract: The present subject matter is directed to apparatus and methods for producing a variable frequency output waveform from a power converter for use in a power generation system, such as a wind turbine power generation system. A voltage divider is employed to provide plural voltage levels to which a multi-level bridge circuit employing selectively activated switches in pairs of switches is coupled. The switches are operated in such a fashion as to produce a generally sinusoidal waveform that may be easily filtered by low cost filters due to the plural voltage levels to produce a generally smooth sine wave from the converter. Such converters may be used in various environments including in pairs in multi-phase power converters.

Abstract: High performance gate drives and methods for driving semiconductor switching elements, such as insulated gate bipolar transistors (IGBTs), are provided. The gate drive can control the voltage applied to the gate of the IGBT to one or more intermediate voltages near the threshold voltage of the IGBT to control dv/dt of the collector-emitter voltage during and the di/dt of the collector current turn off. For instance, a voltage level between the turn on voltage and the turn off voltage can be applied for a first time period to control dv/dt of the collector-emitter voltage and di/dt of the collector current during turn off. Another voltage level between the turn on voltage and the turn off voltage can be applied for a second time period during reverse recovery of a freewheeling diode coupled in parallel with the IGBT.

Abstract: Systems and methods for controlling battery charging are disclosed. According to one embodiment of the disclosure, a method can include receiving battery state information; determining, based on the battery state information, whether to adjust battery models; and, if so, adjusting the battery models.