The invention relates to a method and system for electronic current control for a flexible DC battery pack, in which the battery pack has a plurality of flexibly interconnectable modules having a respective energy store and at least two respective controllable switches and the modules are electrically connected to one another to form a section having a first and a second section end and the two section ends are connected to a respective high-voltage connection, in which the at least two switches of a respective module interrupt a battery current I or interconnect the respective energy store at least in series or parallel with or to bypass the respective energy store of the respectively adjacent module, in which the flexible interconnection of the modules is controlled by a battery control unit and hence a prescribed DC voltage V is provided.

A method of adding a backup power source to a luminaire that includes exposing driver circuitry through a back surface of a housing for a luminaire having a downlight geometry. The housing contains a light engine that is positioned to emit light through a light emission end of the housing. The driver electronics controls power received by the luminaire for powering the light engine. The method may continue with connecting a battery junction box having an electrical pathway opening in reversible engagement to the back surface of the housing by snap fit engagement. The method may further include connecting a backup battery unit to the luminaire by wiring extending from the battery backup unit through the electrical pathway opening in the junction box to the driver electronics for the luminaire.

An apparatus comprises a plurality of voltage sources, one or more processors embedded with the plurality of voltage sources, and memory storing processor executable instructions that, when executed by the one or more processors, cause the apparatus to modify duty cycles of the voltage sources, and to modify timing for each phase of a multiphase cycle. In some cases, the apparatus: transfers, for each phase of the multiphase cycle, power from a different source of a plurality of sources to a load; determines, for each phase of the multiphase cycle, an input voltage associated with the transferred power, an output voltage associated with the transferred power, and current from the source associated with the transferred power; determines a duty cycle associated with the source; modifies duty cycles of the voltage sources; and modifies timing for each phase of the multiphase cycle.

A power quality compensator device and a control method thereof are provided. The power quality compensator device is electrically connected to a power grid and a nonlinear load, and includes a current controller, a converter, a ripple predictor, a processing unit and a voltage controller. The current controller is configured to receive an instruction current and output a switch control signal. The converter is configured to output an output current and an actual DC bus voltage according to the switch control signal. The ripple predictor is configured to receive an intermediate voltage and a first current and output a predicted ripple voltage. The processing unit is configured to output a processing result according to the actual DC bus voltage, the predicted ripple voltage and a reference DC bus voltage. The voltage controller is configured to receive the processing result and output a voltage control signal to the current controller.

A power quality compensator device and a control method thereof are provided. The power quality compensator device is electrically connected to a power grid and a nonlinear load, and includes a current controller, a converter, a ripple predictor, a processing unit and a voltage controller. The current controller is configured to receive an instruction current and output a switch control signal. The converter is configured to output an output current and an actual DC bus voltage according to the switch control signal. The ripple predictor is configured to receive an intermediate voltage and a first current and output a predicted ripple voltage. The processing unit is configured to output a processing result according to the actual DC bus voltage, the predicted ripple voltage and a reference DC bus voltage. The voltage controller is configured to receive the processing result and output a voltage control signal to the current controller.

A control unit for an active filter for reducing resonance in an electric system is provided. The electric system comprises a power source distributing an alternating current to an AC conductor connected to a power consuming unit for distributing the AC to the power consuming unit. The active filter comprises a DC power source and a DC conductor connecting the DC power source to the AC conductor. The control unit comprises: a voltage measurement unit adapter to create a voltage signal on the basis of a measured voltage; a computing unit adapted to compute, using a biquadratic filter, a first compensating current on the basis of the voltage signal for reducing resonance in the electric system and a switching system placed between the DC power source and the DC conductor for creating the calculated first compensating current.

Methods and devices for a home power networking system including a first wireless access point (AP) configured to perform wired communications over a first circuit connected to the first wireless AP. The first wireless AP further performs wireless communications with a second wireless AP, wherein the second wireless access point is connected to a second circuit and is not connected to the first circuit. The first wireless AP provides wireless transport through the second wireless AP to bridge communications between the first circuit and the second circuit.

Methods and devices for a home power networking system including a first wireless access point (AP) configured to perform wired communications over a first circuit connected to the first wireless AP. The first wireless AP further performs wireless communications with a second wireless AP, wherein the second wireless access point is connected to a second circuit and is not connected to the first circuit. The first wireless AP provides wireless transport through the second wireless AP to bridge communications between the first circuit and the second circuit.

An MV DC electrical energy distribution system includes two or more MV DC buses, coupled together in normal operation by a solid state switch. Each MV DC bus is adapted to be electrically coupled to one or more consumers. Each MV DC bus is coupled to one or more MV DC energy storage devices. The MV DC energy storage devices each have a plurality of LV energy storage stacks connected together in series. Each MV DC energy storage device uses a power control unit to distribute the power between different MV DC energy storage strings or to control the power of each MV-energy storage devices individually.

An MV DC electrical energy distribution system includes two or more MV DC buses, coupled together in normal operation by a solid state switch. Each MV DC bus is adapted to be electrically coupled to one or more consumers. Each MV DC bus is coupled to one or more MV DC energy storage devices. The MV DC energy storage devices each have a plurality of LV energy storage stacks connected together in series. Each MV DC energy storage device uses a power control unit to distribute the power between different MV DC energy storage strings or to control the power of each MV-energy storage devices individually.