A method for controlling a battery-powered power supply. The method includes generating a first output from a first power supply within the battery-powered power supply. The first output is coupled to an output bus. The method further includes monitoring a voltage of the output bus, and determining, using a controller of the battery-powered power supply, whether the voltage of the output bus is less than a first predetermined level. The method further includes deactivating the first power supply in response to determining that the voltage of the output bus is below the first predetermined level, and generating a second output from a second power supply within the battery-powered power supply. The second output is configured to be coupled to the output bus. The second power supply has a higher output rating than the first power supply.

A method for controlling a battery-powered power supply. The method includes generating a first output from a first power supply within the battery-powered power supply. The first output is coupled to an output bus. The method further includes monitoring a voltage of the output bus, and determining, using a controller of the battery-powered power supply, whether the voltage of the output bus is less than a first predetermined level. The method further includes deactivating the first power supply in response to determining that the voltage of the output bus is below the first predetermined level, and generating a second output from a second power supply within the battery-powered power supply. The second output is configured to be coupled to the output bus. The second power supply has a higher output rating than the first power supply.

An uninterruptible power supply system includes a plurality of uninterruptible power supplies, each of which includes a rectifier and an inverter and switches between a normal operation mode for normal operation and a load simulation mode for simulating a load.

A power conversion circuit for an uninterruptible power system, including an inductor, a first capacitor, a second capacitor, a first switch, a second switch, a third switch, a first diode, a second diode, and a third diode body, is provided. A terminal of the second switch is electrically coupled to the inductor through the first switch, and another terminal of the second switch is electrically coupled to a neutral wire and the third switch. An anode and a cathode of the first diode are electrically coupled to the first switch and a positive DC bus, respectively. A cathode and an anode of the second diode are electrically coupled to the first switch and the third switch, respectively. A cathode and an anode of the third diode are electrically coupled to the third switch and a negative DC bus, respectively. In addition, an uninterruptible power system using the same is provided.

The invention relates to a central unit (100) for supplying emergency lighting means (101a, 101b) on a DC bus (101), comprising an AC input (103) for receiving an AC supply signal, an AC/DC converter (104) configured to convert the AC supply signal into a DC supply signal, an electrical energy storage (105), in particular a battery, configured to be charged by the DC supply signal, wherein the electrical energy storage (105) is configured to supply electrical power in an emergency situation, and a DC/DC converter (107) configured to convert a DC output signal of the electrical energy storage (105) into a DC bus voltage and to forward the DC bus voltage to the lighting means (101a, 101b) on the DC bus (101) via an output circuit (109), wherein the output circuit (109) is arranged on a modular card (111), and wherein the modular card (111) is detachably connectable to a base body (102) of the central unit (100).

A power supply manager manages power utilization of a first uninterruptible power source and a second uninterruptible power source. A load balancing service retrieves information that is associated with a first power supply unit and a second power supply unit, and determines a first power source state associated with the first uninterruptible power source and a second power source state associated with the second uninterruptible power source. The service may also set the first power supply unit in an active mode based on the first power source state, and set the second power supply unit in a standby mode based on the second power source state. The service may also transition the first power supply unit from the active mode to standby mode, and the second power supply unit from standby mode to the active mode, based on a power imbalance.

A fast-charging method is provided for rapidly charging an electric vehicle at a light-duty charging site comprising a residential dwelling or a small off-grid power station. The fast charging method incorporates an intermediate battery bank, or power buffer, that stores energy between EV charging cycles, then discharges the stored energy into the EV at a higher rate than the primary electric power source for the charging system. The power buffer thereby acts as a power multiplier that accelerates the rate of charge of an electric vehicle. Substantial power multiplication factors are possible at light-duty charging sites, resulting in large improvements in electric vehicle charging rates. The method may be applied using a number of primary power sources including AC from the utility grid, DC from photovoltaic panels, or power from other electric vehicle chargers (including both AC and DC electric vehicle chargers).

A switch arrangement for providing alternative distribution paths in a system for distributing electrical power in a vehicle including electrical power supplies and electrical loads. The switch arrangement includes a first switch configured to be connected to a first electrical element, a second switch configured to be connected to the first electrical element and a second electrical element, and a third switch configured to be connected to the second electrical element and a third electrical element. Each of the first, second, and third switches is independently controllable, and selective operation of each of the first, second, and third switches to its open or closed state interconnects at least two of the first, second, and third electrical elements to establish one of multiple alternative distribution paths to connect one of the power supplies and one of the loads or to connect two of the power supplies.

An uninterruptible power supply device includes a bidirectional chopper that converts a first DC voltage supplied from a battery into a second DC voltage and supplies the second DC voltage to an inverter when a power failure of a commercial AC power supply occurs. The bidirectional chopper includes a capacitor that stabilizes the second DC voltage. The uninterruptible power supply device further includes: a current detector that detects an output current of the battery; and a control circuit that, based on a detection result by the current detector, calculates an estimated temperature increase value of the capacitor every time a predetermined time period elapses, and stops an operation of the bidirectional chopper when the calculated estimated temperature increase value is higher than an upper limit value.

An uninterruptible power supply apparatus includes: an electromagnetic contactor including a first terminal that receives a first AC voltage supplied from an AC power supply and a second terminal connected to an AC node; a capacitor that is connected to a DC line and stores DC power; a converter that transmits and receives electric power between the AC node and the DC line; and a controller. In an activation mode, the controller turns on the electromagnetic contactor after controlling the converter such that a frequency and a phase of a second AC voltage supplied from the converter to the AC node match a frequency and a phase of the first AC voltage. In a normal operation mode after the activation mode, the controller controls the converter such that a DC voltage of the DC node attains to a reference voltage.