The increasing demand for power supply quality and reliability is associated with the development of user’s process level. In the initial development of power, people use it for lighting in general. When blackout occurs, people will light the candles with little complaint. But, when it is mainly used for industrial and agricultural production as well as business, the blackout will cause huge losses.
In the modern times, scientific and technological progress promotes the automation and intellectualization of production, resulting in the new and higher requirements for power quality. The outage of a computer center for 2s may destroy dozens of hours of data processing result or cause millions of economic losses.
In large machine manufacturers, 0.1S voltage dip may cause abnormal production and quality reduction. The continuous finishing production line of automation equipment is extremely sensitive to the interference of power system. Only a fraction of a second of abnormal power supply may cause confusion in the plant, and the loss is enormous.