An alternating current power supply configured to provide a high-voltage alternating current power output from two or more low-voltage alternating current power sources is provided. The alternating current power supply comprises a first alternating current power input, a second alternating current power input, and an alternating current power output having a first output conductor and a second output conductor. The alternating current power supply includes a first switch means for coupling the first alternating current input to the first output connector and the second alternating current input to the second output connector. The first switch means is sequentially responsive to the first current flow followed by the second current flow. The alternating current power supply further comprises an isolation means connected between the first switch means and the alternating current power output, wherein the isolation means is configured to isolate the first current flow from the second current flow.

An alternating current power supply configured to provide a high-voltage alternating current power output from two or more low-voltage alternating current power sources is provided. The alternating current power supply comprises a first alternating current power input, a second alternating current power input, and an alternating current power output having a first output conductor and a second output conductor. The alternating current power supply includes a first switch means for coupling the first alternating current input to the first output connector and the second alternating current input to the second output connector. The first switch means is sequentially responsive to the first current flow followed by the second current flow. The alternating current power supply further comprises an isolation means connected between the first switch means and the alternating current power output, wherein the isolation means is configured to isolate the first current flow from the second current flow.

The present disclosure provides exemplary embodiments of voltage harvesting devices used in power distribution systems, and provides power distribution system architectures utilizing the voltage harvesting devices. Generally, the voltage harvesting devices transform distribution line AC voltages to produce a low wattage output for distribution system communication and control type devices. The voltage harvesting device can operate whether irrespective of the presence of load current.

The present disclosure provides a photovoltaic solar inverter with an AC grid filter without inductance connectable to the AC grid. The inverter comprises: a power module for converting a DC input voltage into a three-phase AC output voltage; a three-phase AC/AC transformer for adapting the three-phase AC output voltage of the power module to the three-phase AC voltage of the AC grid, which has an inductance “L.sub.2”. The three-phase AC/AC transformer comprises a winding on the grid side with an equivalent inductance “L.sub.1”; a capacitor “C”, connected to the winding of the grid side of the three-phase AC/AC transformer. The equivalent inductance “L.sub.1” of the AC/AC transformer, the capacitor “C” and the inductance “L.sub.2” of the AC grid form a high frequency “LCL” filter, eliminating the inductances provided only for forming the LCL filter. The disclosure also provides an AC grid filter without inductance with an “LLCL” typology.

The present disclosure provides a photovoltaic solar inverter with an AC grid filter without inductance connectable to the AC grid. The inverter comprises: a power module for converting a DC input voltage into a three-phase AC output voltage; a three-phase AC/AC transformer for adapting the three-phase AC output voltage of the power module to the three-phase AC voltage of the AC grid, which has an inductance “L.sub.2”. The three-phase AC/AC transformer comprises a winding on the grid side with an equivalent inductance “L.sub.1”; a capacitor “C”, connected to the winding of the grid side of the three-phase AC/AC transformer. The equivalent inductance “L.sub.1” of the AC/AC transformer, the capacitor “C” and the inductance “L.sub.2” of the AC grid form a high frequency “LCL” filter, eliminating the inductances provided only for forming the LCL filter. The disclosure also provides an AC grid filter without inductance with an “LLCL” typology.

An electronic system sharing power of a doorbell includes a switch circuit and an electronic device. The first and second connection terminals of the switch circuit are respectively coupled to two doorbell contacts. The second and third connection terminals of the switch circuit are respectively coupled to two ends of a doorbell. Two power terminals of the electronic device are respectively coupled to two switch contacts. A function circuit of the electronic device is coupled between the two power terminals. In a normal mode, the first connection terminal is conducted to the second connection terminal inside the switch circuit, and the two power terminals are disconnected from each other by a doorbell actuating unit of the electronic device. In a ringing mode, the doorbell actuating unit short-circuits the two power terminals, and the first connection terminal is conducted to the third connection terminal inside the switch circuit.

Systems and methods for an alternating current (AC) input selection for a power transformer are disclosed. In particular, a connector is provided that is pre-wired to utilize internal wiring in the power transformer to provide a desired connection. A first option allows two transformers' input winding to be in series while a second option allows the two transformers' input winding to be in parallel. By moving the wiring into the connector, installation is simplified as the wiring has already been done. The installer need only attach the correct plug based on the desired voltage and couple the plug to the transformer. Further, the manipulation of thick wires is also avoided by the installer, further simplifying the installation process.

Systems and methods for an alternating current (AC) input selection for a power transformer are disclosed. In particular, a connector is provided that is pre-wired to utilize internal wiring in the power transformer to provide a desired connection. A first option allows two transformers' input winding to be in series while a second option allows the two transformers' input winding to be in parallel. By moving the wiring into the connector, installation is simplified as the wiring has already been done. The installer need only attach the correct plug based on the desired voltage and couple the plug to the transformer. Further, the manipulation of thick wires is also avoided by the installer, further simplifying the installation process.

Systems and methods for efficient power conversion in a power supply in a power distribution system are disclosed. In particular, a low frequency transformer having high conversion efficiency is coupled to an input from a power grid. An output from the transformer is rectified and then converted by a power factor correction (PFC) converter before passing the power to the distributed elements of the power distribution system. By placing the transformer in front of the PFC converter, overall efficiency may be improved by operating at lower frequencies while preserving a desired power factor and providing a desired voltage level. The size and cost of the cabinet containing the power conversion circuitry is minimized, and operating expenses are also reduced as less waste energy is generated.

A system and method using four switches connected in an H-bridge (full bridge) topology within a series-connected FACTS device is disclosed. System and method can be used to bypass a FACTS device. The switches in H-bridge are connected to an alternating current (AC) source allowing for various switching states, and enabling non-monitoring mode, local bypass monitoring mode, low-loss monitoring mode, and diagnostic mode of operation.