1. What is a UPS? An Uninterruptible Power System (UPS) is a constant-voltage and constant-frequency uninterruptible power supply comprising an energy storage device and comprising an inverter as its main component. It is mainly used to provide uninterrupted power supply to a single computer, computer network system or other power electronic equipment. When the mains input is normal, the UPS will supply the mains voltage regulator to the load. At this time, the UPS is an AC mains voltage regulator, and it also charges the battery in the machine; When the mains supply is interrupted (an accidental power failure), the UPS immediately supplies 220V AC power to the load by inverting the battery power. This ensures that the load works properly and protects the software and hardware of the load from damage. (Simply put, UPS is a large charging bank) 2, types of UPS (1) Offline uninterruptible power supply Offline uninterruptible power supply offline uninterruptible power supply, also known as the backup uninterruptible power supply, as shown in the figure above. Ordinary mains power supply through the bypass directly to the load, the inverter in the machine is stopped working state, then the UPS power supply is essentially equivalent to a poor performance of the mains voltage regulator, it in addition to the amplitude fluctuation of the mains voltage has been improved, the frequency of voltage instability, waveform distortion and interference from the grid intrusion and other adverse effects basically no improvement. Only in the event of a power outage is the battery energy converted into AC through the inverter to provide power to the load. The characteristics of offline uninterruptible power supply: A, when the mains is normal, the offline UPS does not process the mains and directly output to the load, so the mains noise and surge suppression ability is poor; B, there is conversion time C, the worst protection performance D, simple structure, small volume, light weight, easy control, low cost. (2) on-line uninterruptible power supply
When the mains power supply is normal, it will first rectify the mains AC power supply into DC power supply, and then carry out pulse width modulation, filtering, and then the DC power converted into sine wave AC power supply to the load by the inverter. Once the mains is interrupted, the direct current provided by the battery is changed to provide sine-wave AC power to the load through the inverter. Therefore, for the online UPS power supply, under normal circumstances, regardless of whether there is mains power, it is powered by the UPS power supply inverter to the load, so as to avoid all the effects of voltage fluctuations and interference from the mains grid. Obviously, the power supply quality of the online UPS is obviously better than that of the backup UPS. Because it can realize the load of stable frequency, stable voltage power supply, and by the mains power supply to battery power supply, its conversion time is zero. Really provide users with high-quality voltage and frequency stability of pure sine wave power supply, so as to provide power protection in line with the needs of network system.
