UNINTERRUPTIBLE POWER SUPPLY CIRCUIT

An uninterruptible power supply circuit includes an inverter circuit configured to be connected to a first AC power grid, the power supply circuit moreover being configured to adopt a first configuration for supplying power to the first AC power grid from a second AC power grid, wherein first configuration a power factor correction circuit is configured to be connected to the second AC power grid so as to deliver a DC voltage to the inverter circuit, the power factor correction circuit comprising an inductor, and a first switch branch pertaining to the power factor correction circuit and the inverter circuit; and a second configuration for supplying power to the first AC power grid from a DC voltage source, wherein second configuration a DC-DC converter circuit is configured to be connected to the DC voltage source so as to deliver a DC voltage to the inverter circuit, the inductor moreover pertaining to the DC-DC converter circuit.