A control device (2) of an inverter converts electrical power generated by a solar cell (3) into alternating current power connecting to an electric power system (7). The control device includes: an alternating current voltage sensor (14) sensing a system voltage (Vr) of the electric power system; an MPPT executer (23) controlling a direct current voltage (Vdc) applied to the inverter (1) to cause the electrical power output from the solar cell (3) to be a maximum when the direct current voltage (Vdc) is higher than a lower limit (VL); a direct current voltage lower limit calculator 22 reducing the lower limit (VL) when the system voltage (Vr) is lower than a predetermined voltage; and an electrical power controller (25) controlling reactive power based on the system voltage (Vr), the reactive power being output from the inverter (1).

A grid connection power conversion device for connecting a distributed power supply to a three-phase commercial power system is provided. The power conversion device comprises an inverter, an instantaneous voltage detection circuitry to detect a maximum three-phase instantaneous voltage value of the commercial power system, a line voltage detection circuitry to detect a maximum value of each of three line voltages, an instantaneous voltage drop detection circuitry to detect an instantaneous voltage drop, and an output current control circuitry to control an output current value from the inverter. When the instantaneous voltage drop detection circuitry detects an instantaneous voltage drop, the output current control circuitry reduces the output current value from the inverter to an output current value corresponding to a minimum value among the four maximum voltage values which are the maximum three-phase instantaneous voltage value and the maximum values of the three line voltages.

A system of surge suppressor units is connected at multiple locations on a power transmission and distribution grid to provide grid level protection against various disturbances before such disturbances can reach or affect facility level equipment. The surge suppressor units effectively prevent major voltage and current spikes from impacting the grid. In addition, the surge suppressor units include various integration features which provide diagnostic and remote reporting capabilities required by most utility operations. As such, the surge suppressor units protect grid level components from major events such as natural geomagnetic disturbances (solar flares), extreme electrical events (lightning) and human-generated events (EMPs) and cascading failures on the power grid.

One or more techniques and/or systems are provided for facilitating a shutdown of output power from an energy panel arrangement to an inverter. A shutdown implementation module is coupled between an energy panel arrangement and an inverter that converts DC power from the energy panel arrangement to AC power for an AC power grid. A communication connection is established, over a power-line communication line, between the shutdown implementation module and a shutdown controller associated with the inverter. Responsive to identifying a loss of the communication connection or receiving a shutdown instruction over the power-line communication line, the shutdown implementation module shuts down output power from the energy panel arrangement to the inverter. The shutdown implementation module may be located within a threshold distance from the energy panel arrangement (e.g., within about 10 feet) so that the output power may be shutoff within a threshold timespan (e.g., within about 10 seconds).

A low-voltage circuit in a bidirectional DC-DC converter converts output AC power from a high-voltage circuit to DC power to charge a smoothing reactor and discharge the smoothing reactor, and includes an active snubber circuit including switching elements and each having a backward diode and a snubber capacitor. The snubber capacitor of the active snubber circuit has its one end connected to a drain end of the switching elements and has its other end connected to a node between a center tap of a high-frequency transformer and a smoothing reactor.

A modular system for autonomous food assembly includes: a skid operable in a first configuration configured to transiently install on a vehicle and in a second configuration configured to transiently install in a kiosk; a set of food dispensing modules configured to transiently install on the skid and store and dispense food based on food orders; and a fixed infrastructure configured to distribute power from a first power source in the truck to the set of food dispensing modules in the first configuration, from a second power source in the fixed kiosk to the set of food dispensing modules in the second configuration, and to the set of food dispensing modules; a controller installed on the skid and configured to receive food orders and control the set of food dispensing modules to dispense food orders from the truck in the first configuration and from the kiosk in the second configuration.

The present disclosure is directed to energy storage and supply management system. The system may include one or more of a control unit, which is in communication with the power grid, and an energy storage unit that stores power for use at a later time. The system may be used with traditional utility provided power as well as locally generated solar, wind, and any other types of power generation technology. In some embodiments, the energy storage unit and the control unit are housed in the same chassis. In other embodiments, the energy storage unit and the control unit are separate. In another embodiment, the energy storage unit is integrated into the chassis of an appliance itself.

The present disclosure is directed to energy storage and supply management system. The system may include one or more of a control unit, which is in communication with the power grid, and an energy storage unit that stores power for use at a later time. The system may be used with traditional utility provided power as well as locally generated solar, wind, and any other types of power generation technology. In some embodiments, the energy storage unit and the control unit are housed in the same chassis. In other embodiments, the energy storage unit and the control unit are separate. In another embodiment, the energy storage unit is integrated into the chassis of an appliance itself.

A power converting device includes a DC-DC converting circuit, a DC-AC converting circuit, and an insulation detecting circuit. The DC-DC converting circuit is configured to convert a DC input voltage to a DC bus voltage. The DC-AC converting circuit is electrically coupled to the DC-DC converting circuit and configured to convert the DC bus voltage to an AC voltage. The insulation detecting circuit is electrically coupled between the DC-DC converting circuit and the DC-AC converting circuit. The insulation detecting circuit is configured to detect a ground impedance value of the power converting device according to the DC bus voltage.

Disclosed are a power optimization method and an apparatus therefor, and a photovoltaic device and a photovoltaic system. The power optimization of a photovoltaic assembly can be realized when a series connection architecture or a parallel connection architecture is used for the photovoltaic assembly. The method includes: power optimization apparatuses carrying out MPPT processing on photovoltaic assemblies according to operating parameters of the photovoltaic assemblies corresponding to the power optimization apparatuses on a one-to-one basis (101); and controlling the photovoltaic assemblies according to MPPT processing results so that power states of the photovoltaic assemblies are optimized (102). By means of providing a power optimization apparatus for each photovoltaic assembly, the power optimization apparatus carries out MPPT processing on the corresponding photovoltaic assembly, thereby preventing the occurrence of power mismatch.