Uninterrupted power system

Abstract

The invention provides an uninterrupted power system. When a first power source of the system breaks down, a second power source discharges power to a direct current bus through a bi-directional power converting unit in the process that the first power source is switched to the second power source for power supplying through a switching unit, and during the switching process, electric energy stored in the direct current bus is discharged in a short time, the discharged current of the second power source and the discharged current of the direct current bus are output to the system output end through the direct current bus, and it is guaranteed that the voltage output by the direct current bus during the neutral position period of action of the switching unit is stable; due to the fact that the discharged current of the bi-directional power converting unit supports the voltage of the direct current bus in the switching process, the requirement for the capacitance value of the direct current bus can be lowered, and meanwhile safe and reliable switching of a switching device is guaranteed; due to the fact that the bi-directional power converting unit only supports the voltage of the direct current bus in a short time when the switching device acts, the specification and size of a charger unit can be greatly reduced.

Description

technical field [0001] The invention relates to the field of uninterruptible power supply, in particular to an uninterruptible power supply system. Background technique [0002] At present, only a few local areas in my country have just solved the problem of power shortage, and most regions and big cities are still facing the urgent problem of power supply shortage, and the quality of power supply cannot be guaranteed. Mains power cannot provide the clean, stable power that sensitive electronic equipment requires, and users are ultimately responsible for the health and safe operation of their equipment. Even in the long-electrified United States and other Western countries, the quality of the grid is far from reliable. Due to the quality of the power grid itself and various accidental factors, coupled with the destruction of natural disasters, voltage surges, electromagnetic noise, continuous high voltage, continuous low voltage and other bad grid phenomena are common in de...

AI Technical Summary

Problems solved by technology

[0005] In normal use, by controlling the switching device, the UPS can choose mains power supply or battery power supply, but when the mains power and battery are switched, there is a certain gap period during the switching process, that is, neither the mains input nor the battery input , the time is usually several milliseconds to tens of milliseconds. The energy stored in the DC bus capacitor (1 / 2CU2) can keep the output voltage uninterrupted, and all the loads are powered by the stored energy of the DC bus. Large, UPS volume cost competitiveness declines

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