Electrically connecting a first node of a first power grid to a second node of a second power grid includes: determining a phase angle of at least one phase of an AC voltage at the first node in the first power grid; determining a phase angle of at least one phase of an AC voltage at the second node in the second power grid; determining a phase angle metric based on comparing the phase angle of the AC voltage in the first power grid to the phase angle of the AC voltage in the second power grid; comparing the phase angle metric to a phase angle threshold; and if the phase angle metric is equal to or exceeds the phase angle threshold, controlling a dispatchable energy source in the first power grid in a P-Q control mode to adjust the phase angle of at least one phase of the AC voltage at the first node.

An alternating current (AC) module system includes branch circuits and a main service panel to receive power from the branch circuits. A photovoltaic (PV) supervisor is located between the branch circuits and the panel. The PV supervisor aggregates the power from the branch circuits. The PV supervisor also performs a nonredundant operational function for one or more of the branch circuits. The PV supervisor includes a gateway device to permit control of the operational functions.

Disclosed is an all-in-one emergency shed that can supply electricity and potable drinkable water during an emergency when electrical grid power is not available and water sources may be contaminated. The emergency shed can use battery banks from electric cars to store electrical energy for emergencies and can store electrical energy in electric car battery banks that are charged during off-peak times and resold to the utility company during peak demand periods.

A method for controlling a wind power installation includes measuring a grid voltage of an electrical power supply grid, setting a DC-link voltage at a converter of the wind power installation depending on the measured grid voltage and using a first time constant and a second time constant, wherein the first time constant is different than the second time constant.

A method for controlling a wind power installation includes measuring a grid voltage of an electrical power supply grid, setting a DC-link voltage at a converter of the wind power installation depending on the measured grid voltage and using a first time constant and a second time constant, wherein the first time constant is different than the second time constant.

A system for load balancing on a multi-phase power line connected to a single phase lateral power line, includes a contactor configured to selectively connect each phase of the multi-phase power line to the single phase lateral power line. There is a phase change device connected in parallel with the contactor and a controller. During the phase change state, the controller connects the input of the phase change device to the multi-phase power line and connects the output of the phase change device the single phase lateral power line. The controller causes the phase change device to output a voltage to the single phase lateral line initially aligned with the first phase and then rotated to align with the second phase and causes the contactor changes connection to the second phase of the multi-phase power line and disconnect the phase change device from the power lines.

An electrical distribution grid energy management and router device, or GER device, may be installed in a distribution grid, and route power from power supply to one or more power consumers. The GER devices described herein may provide platforms to add one or more features to a distribution transformer, provide additional features and benefits to both the utility company and end consumer, and may serve as a platform for providing other features, such as multi-layer protection systems for detecting, among other things, one or more fault conditions, and responding to such conditions when detected. A GER device may include sensors to measure electrical properties of incoming and outgoing power, and may include an electrical circuit layer having a central DC power stage.

A power conversion system includes a plurality of power conversion devices connected to a plurality of AC systems, respectively. The power conversion devices are further connected to a common DC circuit. The power conversion system further includes a start-up device to start up each power conversion device. The start-up device selects an AC system that satisfies a defined condition relating to power supply capability from among the plurality of AC systems based on system information of the plurality of AC systems and starts up a power conversion device connected to the selected AC system.

An electrical distribution site energy management and router device, or SER device, may be installed between a customer premises and a distribution grid, and one or more alternative energy sources and energy storage devices may be electrically connected to the SER device. The SER device may intelligently route power from alternative energy sources to the customer premises, energy storage devices, even to the grid, through various modes of operation. The SER device may efficiently and economically route power during peak electricity price periods and outside of peak periods.

Electrically connecting a first node of a first power grid to a second node of a second power grid includes: determining a phase angle of at least one phase of an AC voltage at the first node in the first power grid; determining a phase angle of at least one phase of an AC voltage at the second node in the second power grid; determining a phase angle metric based on comparing the phase angle of the AC voltage in the first power grid to the phase angle of the AC voltage in the second power grid; comparing the phase angle metric to a phase angle threshold; and if the phase angle metric is equal to or exceeds the phase angle threshold, controlling a dispatchable energy source in the first power grid in a P-Q control mode to adjust the phase angle of at least one phase of the AC voltage at the first node.