An AC power converter converts power from an AC power source to an AC load. A DC power holding source is coupled to an input half-bridge switch, a common half-bridge switch and an output half-bridge switch. A controller is coupled to at least two of the input half-bridge switch, the common half-bridge switch, and an output half-bridge switch. The controller switches the input half bridge at the first switching frequency in boost mode and at the line frequency in buck mode. The controller also switches the output half bridge switch at the first switching frequency in buck mode and at the line frequency in boost mode. Input and output low pass filters can eliminate switching frequency energy from entering the AC source and load. The converter maintains a DC power holding source voltage slightly above peak AC input voltage and significantly less than twice the peak AC input voltage.

The present specification relates to a power supply device and a power supply system capable of uninterrupted power supply, which includes a circuit breaker for regulating connection to a power bus to which a plurality of power supply devices are connected, wherein the circuit breaker is opened or closed according to various situations occurring in the system so as to control power supply and demand.

The present specification relates to a power supply device and a power supply system which enable uninterruptible power supply, wherein a circuit breaker is provided in a power bus to which a plurality of power supply devices are connected, so as to switch on/off the connected power supply devices, and thus the UPS function can be performed among the plurality of power supply devices by opening or closing the circuit breaker according to various situations occurring in the system to control power reception and supply.

An uninterruptible power supply (UPS) includes a rectifier circuit coupled to an AC input and configured to produce a DC voltage between first and second DC buses, an inverter circuit coupled to the first and second DC buses and configured to produce an AC voltage at the AC output. The UPS further includes an auxiliary power circuit comprising third and fourth DC buses configured to be coupled to a DC power source and third and fourth capacitors coupled between respective ones of the third and fourth DC buses and the neutral and respective first and second switches configured to couple and decouple respective ones of the third and fourth DC buses to and from respective ones of the first and second DC buses. The third and fourth capacitors may have capacitances greater than capacitances of the first and second capacitors.

An electrical system for a mobile power generation device and a mobile power generation device are disclosed. The electrical system includes an electrical cabin and a generator switch cabinet located inside the electrical cabin and including a generator switch device, the generator switch device being configured to connect or disconnect the generator of the mobile power generation device from an external load, the generator switch cabinet further includes a first output end configured to be electrically connected to the external load through a connection conductor, the first output end includes a connection terminal or a connector, the electrical cabin includes a first bottom plate, the generator switch cabinet is arranged on the first bottom plate, and the first bottom plate includes a first hollow portion, and an orthographic projection of the generator switch cabinet on the first bottom plate is at least partially overlapped with the first hollow portion.

A power converter with a common DC power source includes a DC power source and at least two power modules. Each of the power modules is coupled with each other and coupled to the DC power source. Each of the power module includes a coupled inductive component coupled to the DC power source, a DC output conversion unit coupled to the coupled inductive component, and a capacitor group having a coupling point. By using the coupled inductive component, it is to solve the problem of return current between the power modules caused by coupling multiple coupling points to each other.

A method for operating a power factor correction (PFC) circuit of an uninterruptible power supply (UPS) apparatus is provided. The PFC circuit includes two T-type converters, and each of the T-type converters includes four switching tubes. The method includes: converting AC input voltage into a positive bus voltage across a first capacitor and a negative bus voltage across a second capacitor that is connected in series with the first capacitor when the UPS apparatus is operated under a normal supply mode; and controlling conduction states of the switching tubes of the T-type converters to balance the positive bus voltage and the negative bus voltage when the UPS apparatus is operated under a battery supply mode.

In an uninterruptible power supply apparatus, AC current, which includes a feedback component having a value corresponding to deviation between terminal-to-terminal voltage of a capacitor and reference voltage, and a feed forward component obtained by multiplying load current by a gain, is passed into a converter such that the terminal-to-terminal voltage of the capacitor becomes the reference voltage. The gain is set to a first gain in an iverter power feed mode and a bypass power feed mode, and the gain is set to a second gain smaller than the first gain in a switching period of switching between the inverter power feed mode and the bypass power feed mode, to prevent the terminal-to-terminal voltage of the capacitor from exceeding an upper limit voltage in a lap power feed mode.

An uninterruptible power supply (UPS) converter circuit includes a controlled switching element, a filter capacitor, and a split DC capacitor comprising a plus DC capacitor and a minus DC capacitor split at a DC-link mid-point, connected to each other at the DC-link mid-point on a respective first side. A second side of the input filter capacitor at an AC point is coupled via an inductor element to a second side of the controlled switching element, the second side of the controlled switching element being coupled to the second side of the plus DC capacitor and the minus capacitor. The controlled switching element operates is configured to be controlled such that a current from the AC point via the inductor element flows alternatingly to either the plus DC output capacitor or the minus DC capacitor, and to the DC-link mid-point, respectively, thereby discharging the input filter capacitor.

According to an aspect of the present disclosure, an uninterruptible power supply (UPS) system is provided. The UPS system includes a first input configured to be coupled to an input power source, a second input configured to be coupled to an energy storage device, an output configured to provide output power, a power conversion circuit (PCC) configured to convert power received from at least one of the input power source or the energy storage device, an output circuit coupled to the PCC and the output, and a controller. The PCC includes a first inductor and a second inductor magnetically coupled to the first inductor. The controller is configured to control the PCC to provide, via the first inductor, DC power derived from the input power source to the output circuit, and provide, via the first and second inductors, DC power derived from the energy storage device to the output circuit.