Smooth switching device and method for double power supplies

摘要

A smooth switching device and method for double power supplies. The devices includes a main/backup power supply switching unit (1), a relay control unit (3), a charge management unit (2), a main power supply switching auxiliary unit (4) and a backup power supply switching auxiliary unit (5). The device and the method enable the main power supply (200) and the backup power supply (300) which supply power for electric equipment (100) to be switched smoothly, so that it is not easy for the electric equipment (100) to be disconnected with the power supplies and the fluctuation of a load voltage is small. Moreover, the device doesn't need a bulk capacitor used for auxiliary switching and doesn't need to be used together with a radiator.

主权项

1. A device for smoothly switching between double power supplies, which is used for providing a smooth switch between a main power supply and a backup power supply which supply power to electric equipment, wherein the device comprises:
a main/backup power supply switching unit for switching between the main power supply and the backup power supply by a switch of a stationary contact of a relay in the main/backup power supply switching unit between a first movable contact and a second movable contact; a relay control unit for detecting output voltages of the main power supply and the backup power supply, and controlling the switch of the stationary contact of the relay between the first movable contact and the second movable contact according to a detected result; a charging management unit for detecting the output voltage of the backup power supply, and controlling the main power supply to charge the backup power supply when the output voltage of the backup power supply is lower than a preset charging threshold; a main power supply switching auxiliary unit for providing a continuous current to the electric equipment during the switch of the stationary contact to the first movable contact of the relay, wherein the main power supply switching auxiliary unit is connected between the main power supply and the electric equipment; a backup power supply switching auxiliary unit for providing a continuous current to the electric equipment during the switch of the stationary contact to the second movable contact of the relay, and disconnecting the backup power supply when the main power supply is disconnected and the output voltage of the backup power supply is lower than a preset over discharging threshold, wherein the backup power supply switching auxiliary unit is connected between the backup power supply and the electric equipment.