The role of uninterruptible power supply (UPS backup power supply)

Uninterruptible power supply is a constant voltage and frequency uninterruptible power supply with energy storage device and inverter as the main component. Its main function is to provide uninterruptible power supply for a single computer, computer network system or other power electronic equipment. When the mains input is normal, the UPS uninterruptible power supply stabilizes the mains voltage and provides it to the load. At this time, the UPS power supply is equivalent to an AC mains voltage stabilizer, and it also charges the battery in the machine; when the mains power is interrupted, the UPS will immediately use the power of the battery in the machine to continue to supply AC power to the load through the inverter conversion method, so that the load maintains normal operation and protects the load software and hardware from damage. In addition to uninterruptible power supply, the uninterruptible power supply also has eight major functions.

1. The role of uninterruptible power supply (UPS backup power supply):

1). Power failure protection function:When the mains power grid is instantly out of power, the uninterruptible power supply (UPS backup power supply) system will immediately convert the UPS battery DC power into AC power to continue to power the load, avoiding the inconvenience and loss caused by power failure.

2). Voltage stabilization:The mains voltage is easily affected by the distance and quality of the power transmission line. The voltage of users closer to the substation is higher, and the voltage of users farther from the substation is lower. Excessive or low voltage will affect the quality and service life of the user's instruments and equipment. In more serious cases, it will damage the equipment and cause significant losses to the user. The use of an uninterruptible power supply (UPS backup power supply) system can provide a stable voltage supply for user equipment, ensuring the normal operation of the equipment and extending its service life.

3). Surge protection:Usually, the uninterruptible power supply (UPS backup power supply) system will have a tip discharge design to absorb surges, avoid affecting the efficiency and life of the equipment due to surge problems, and provide protection for the equipment.

4). High and low voltage protection:When the mains voltage is high or low, the voltage stabilizer (AVR) in the uninterruptible power supply (UPS backup power supply) keeps the mains voltage within a safe range to ensure that the equipment can operate normally. When the high and low voltages exceed the usable range, the uninterruptible power supply (UPS backup power supply) system will start the battery power supply to ensure the continuous operation of the equipment.

5). Harmonic distortion protection:When electricity is transmitted to the user end through the transmission and distribution lines, the voltage waveform is distorted, and the fundamental current changes to generate harmonics. Harmonics will affect the use of equipment. Through uninterruptible power supply (UPS backup power supply), stable and high-quality power can be provided for the equipment, effectively improving the operating efficiency and life of the equipment.

6). Stable frequency function:Frequency is the cycle of the change of the mains power every second, and 50Hz is 50 cycles per second. When the mains generator is running, the sudden change in the power consumption of the user end will cause the change in speed, which will make the converted power frequency uncertain. The power converted by the uninterruptible power supply (UPS backup power supply) can provide a stable frequency to ensure the normal operation of the equipment.

7). Instantaneous protection:The mains power sometimes has voltage surges and dips or instantaneous voltage drops. Such problems will affect the accuracy of the equipment. In severe cases, it will damage the precision equipment and cause losses to the user. The uninterruptible power supply (UPS backup power supply) system can provide stable voltage to protect the equipment.

8). The role of suppressing transverse mode and common mode noise:Transverse mode noise is generated between the live wire and the neutral wire; common mode noise is generated between the live wire, the neutral wire and the ground wire. Invisible power problems are hard to prevent, and they endanger instruments and equipment at all times, causing losses to users. Uninterruptible power supply (UPS backup power supply) escorts instruments and data, ensures the normal operation of equipment and extends the service life of equipment.

2. Main technical parameters of uninterruptible power supply (UPS backup power supply):

1). Input parameters:Input voltage range, according to the situation of low power grid quality, a wider range of uninterruptible power supply (UPS backup power supply) should be selected. The current range of uninterruptible power supply (UPS backup power supply) designed with thyristor is ±25%. If this value is exceeded, the failure rate of uninterruptible power supply (UPS backup power supply) will increase; uninterruptible power supply (UPS backup power supply) should have automatic protection functions for three-phase input phase sequence errors and three-phase phase loss input.

2). Output parameters:Static stability of output voltage, medium and large uninterruptible power supplies (UPS backup power supplies) is ±1%; transient voltage fluctuation value of output voltage, medium and large uninterruptible power supplies (UPS backup power supplies) is less than ±5%; adjustable range of output voltage.

3). Rated operating parameters:Rated output power; rated maximum output and input current; rated output and input frequency, both of which are standard 50Hz in my country; nominal input and output voltages, determined according to the way of input and output lines.

4). Other parameters:The mean time between failures is 200,000 to 400,000 hours (large UPS power supply), 150,000 to 220,000 hours (medium UPS power supply); parallel capability, requiring UPS uninterruptible power supply to have direct parallel output capability, the current imbalance of each uninterruptible power supply (UPS backup power supply) output current is 2% to 5%, and this value should be as small as possible; it should have remote monitoring, fault alarm, and operation status recording functions; it should have lightning protection, surge suppression, and anti-static discharge functions.