Abstract : This article briefly introduces the impact of power grid fluctuations on transmission equipment and its solutions. Keywords : power grid fluctuations, frequency converter, undervoltage surge absorber 1 Introduction With the widespread application of many AC and DC transmission devices in Baosteel, product quality has been improved and maintenance costs have been saved. Due to the high requirements of power quality for speed control devices, power grid voltage fluctuations can affect the normal operation of equipment, causing undervoltage tripping of units, damage to speed control devices, steel pile-up or belt breakage, seriously affecting production. According to incomplete statistics, the events of voltage drop in Baosteel's power grid caused by Shanghai power grid failures from 1998 to 2004 are shown in Table 1 below. In order to reduce the impact of power grid fluctuations on equipment, it is necessary to analyze the impact of voltage fluctuations on the operation of transmission equipment and formulate corresponding countermeasures. [b]2 Impact of Power Grid Voltage Fluctuations on Electrical Equipment 2.1 Impact of Power Grid Voltage Rise on Electrical Equipment[/b] Since electrical equipment is designed to withstand a certain overvoltage (within 5%-10%), it can operate normally when the magnitude of the power grid voltage rise is relatively small, but it still has a certain impact on its operation. When the rise in grid voltage exceeds the safe operating range of electrical equipment, it can cause some electrical equipment to malfunction or even be damaged. (1) For power supply and distribution, when the grid voltage rises, the power supply and distribution system can generally operate normally, but the excitation current of the contactor and transformer coils increases, the noise of the coils increases, and the losses increase; (2) Since most electronic products have DC voltage regulation circuits, when the voltage rise is not large, the electronic products can operate normally; when the voltage rise is large, it can cause the electronic circuit devices to break down and the equipment to be damaged; (3) The speed of asynchronous motors such as fans and pumps operating at power frequency increases, and the motor current decreases; (4) For AC variable frequency motors, since most variable frequency speed control devices use AC-DC-AC voltage type frequency converters. [b][align=center]For details, please click: The impact of grid voltage fluctuations on electrical transmission equipment and countermeasures[/align][/b]