A grid independent operation control unit includes a load current estimator to estimate a load current supplied to stand-alone power system in accordance with an output current of the inverter and an output voltage, and a feedback controller configured to PWM control the inverter at a duty ratio feedback calculated to cause the inverter to output an output voltage command value in accordance with the output voltage and the load current. The feedback controller is configured to PWM control the inverter at a duty ratio feedback calculated for output of a normalized output voltage command value obtained by normalizing the output voltage command value with the DC bus voltage in accordance with normalized output voltage obtained by normalizing the output voltage with the DC bus voltage and normalized load current obtained by normalizing the load current with the DC bus voltage.

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 communications services, local and remote management, and intelligence to components of the distribution grid. 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 GER device may include a physical layer providing a communications platform for one or more communication devices that may communicate with other GER devices to form a micro-grid, a utility, power consumers, third parties, and other electrical devices.

An intelligent user-side power management device (PMD) that has an optional energy storage unit and can interface with a utility grid or microgrid to eliminate power theft and efficiently provide clean energy to the users of the grid while helping the grid to do smart demand response management, particularly for renewable energy based grids that need to efficiently manage the slack due to the large variability in power generation through these energy sources.

A single-phase Energy Utilization Tracker (EUT) inverter that comprises two DC/AC conversion modules. At any time, the two modules combined can sequentially extract and convert most the power provided by a DC energy source into two AC power (voltage) trains. The first AC power (voltage) train conforms to the power grid convention; while the second AC power train has a 90 degree phase difference to the specific power line pair. In according to the principle described herein, this single-phase EUT inverter further comprising a phase adjuster to adjust the phase of the second AC power (voltage) train by 90 degrees to become synchronous with the first AC power train; both AC power trains being then suitable to deliver into the same power line.

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.

SOGI based apparatus and methods for providing balanced three phase output signals free of harmonics, DC components and imbalance present in the input signals, are disclosed. In addition, such apparatus and methods for providing corresponding output signals which are drift-free integrals of the input signals and which signals may enable the control of a power electronics inverter for improved and robust grid power injection and for motor control are disclosed.

The disclosed system provides an adaptive control system technique generally related to distributed energy resources (DERs) located in distribution circuits. More specifically, the system technique relates to a DER with both active and reactive generation capability. In an embodiment, the system measures a voltage phase angle and a current phase angle of distribution feeder circuit, and measures a voltage value output by a power converter. The system calculates an active power setpoint value and a reactive power setpoint value of the power converter based on the measured voltage value, and the measured voltage phase angle and current phase angle. The system then sets the active and reactive power setpoint values on the power converter. The disclosed system automatically adjusts the setpoints to real-time load characteristics of the distribution feeder circuit, increases distribution feeder hosting capacity, and enables DERs to integrate in distribution feeders more efficiently.

The disclosed system provides an adaptive control system technique generally related to distributed energy resources (DERs) located in distribution circuits. More specifically, the system technique relates to a DER with both active and reactive generation capability. In an embodiment, the system measures a voltage phase angle and a current phase angle of distribution feeder circuit, and measures a voltage value output by a power converter. The system calculates an active power setpoint value and a reactive power setpoint value of the power converter based on the measured voltage value, and the measured voltage phase angle and current phase angle. The system then sets the active and reactive power setpoint values on the power converter. The disclosed system automatically adjusts the setpoints to real-time load characteristics of the distribution feeder circuit, increases distribution feeder hosting capacity, and enables DERs to integrate in distribution feeders more efficiently.

A system and a method for connecting electrical load(s) to a first power source and a second power source including a switching device and a controller. The switching device includes a first semiconductor device pair and a second semiconductor device pair. The controller configured to receive a first set of electronic signals corresponding to a condition of the first power source and the second power source, isolate the first power source or the second power source from the one or more loads by transmitting a first set of control signals to the switching device, receive a second set of electronic signals corresponding to the condition of the first power source and the second power source, and connect the first power source or the second power source to the one or more loads by transmitting a second set of control signals to the switching device.

A system and a method for connecting electrical load(s) to a first power source and a second power source including a switching device and a controller. The switching device includes a first semiconductor device pair and a second semiconductor device pair. The controller configured to receive a first set of electronic signals corresponding to a condition of the first power source and the second power source, isolate the first power source or the second power source from the one or more loads by transmitting a first set of control signals to the switching device, receive a second set of electronic signals corresponding to the condition of the first power source and the second power source, and connect the first power source or the second power source to the one or more loads by transmitting a second set of control signals to the switching device.