Abstract: A system and method for operating a photovoltaic element at or near a maximum power point. A maximum power point tracker changes a voltage or current set point of a photovoltaic element in sequential discrete steps, measuring an output power at each step after a predetermined settling time. A slope of a power-voltage curve is then estimated and the slope is corrected for irradiance changes. Finally, an operating voltage or current of the photovoltaic element is adjusted based on the slope of the power-voltage curve and other factors, causing the photovoltaic element to operate at or near its maximum power.

Abstract: A system and method for detecting islanding in a Distributed Generation utility grid is described. In some examples, the system, via an inverter, injects a frequency disturbance to a location of the utility grid associated with a DG generator, measures both the frequency error due to the disturbance and the frequency drift of the location of the utility grid, and determines islanding based on a maximum value of the frequencies. In some cases, the system is able to reduce or minimize the Non-Detection Zone of the inverter by detecting islanding without always relying on a detectable frequency error due to an injected waveform.

Abstract: An inverter capable of supplying power to utility grids of varying line voltages is described. In some examples, the inverter contains multiple output taps that are selected to output power to the utility grid based on the voltage of the utility grid. In some examples, the inverter includes a multi-pin connector that connects with one of multiple receptacles associated with a desired voltage configuration. In some examples, the inverter is capable of adapting to a defined line voltage in two steps.

Abstract: Inverter bus structures, assemblies and associated methods are disclosed herein. One embodiment of the disclosure, for example, is directed to a power inverter including an inverter module for converting DC power to AC power, a printed circuit board carrying a capacitor array, a DC power source, and a bus structure. The bus structure is physically coupled each of the inverter module and the printed circuit board, and the bus structure electrically couples each of the inverter module, the printed circuit board to the DC power source.

Abstract: An inverter has three redundant modes of thermal protection providing fire protection and secures protection of the inverter from thermal damage. An embodiment of the present invention is disclosed wherein thermal transducers or actuators are located on a control circuit board, a heat sink, and a power circuit board. Two of the modes of thermal protection are active and one is passive.

Abstract: A method for the startup of a solar power inverter in which a waiting period is increased between successive attempts to start the inverter. This method allows the inverter to start up in a reasonable amount of time while avoiding excessive cycling during prolonged periods of low light.

Abstract: A method for the startup of a solar power three-phase inverter in which a waiting period is increased between successive attempts to start the inverter. This method allows the inverter to start up in a reasonable amount of time while avoiding excessive cycling during prolonged periods of low light.

Abstract: A method for detecting and interrupting an electrically islanded condition for a grid connected current source inverter is disclosed in which: A line voltage frequency is monitored at a cycle or sub cycle resolution. Current output from the inverter is periodically phase shifted. If voltage is observed to follow the phase shift of the current output an islanding error signal is generated causing the inverter to stop injecting power onto the line.

Abstract: An inverter capable of supplying power to utility grids of varying line voltages is described. In some examples, the inverter contains multiple output taps that are selected to output power to the utility grid based on the voltage of the utility grid. In some examples, the inverter includes a multi-pin connector that connects with one of multiple receptacles associated with a desired voltage configuration. In some examples, the inverter is capable of adapting to a defined line voltage in two steps.

Abstract: Inverter bus structures, assemblies and associated methods are disclosed herein. One embodiment of the disclosure, for example, is directed to a power inverter including an inverter module for converting DC power to AC power, a printed circuit board carrying a capacitor array, a DC power source, and a bus structure. The bus structure is physically coupled each of the inverter module and the printed circuit board, and the bus structure electrically couples each of the inverter module, the printed circuit board to the DC power source.

Abstract: An inverter component layout and mounting bracket are disclosed which allow for electrical components, or the inverter as a whole to be replaced easily in the field. The disclosed mounting bracket and component layout also improve the heat rejection properties of the inverter.

Abstract: A system and method for detecting islanding in a Distributed Generation utility grid is described. In some examples, the system, via an inverter, injects a frequency disturbance to a location of the utility grid associated with a DG generator, measures both the frequency error due to the disturbance and the frequency drift of the location of the utility grid, and determines islanding based on a maximum value of the frequencies. In some cases, the system is able to reduce or minimize the Non-Detection Zone of the inverter by detecting islanding without always relying on a detectable frequency error due to an injected waveform.