The WLD2975 Frequency Voltage Protection Device (also known as the Low Frequency Low Voltage Load Shedding Device) is an intelligent protection equipment used for frequency and voltage stability control in power systems. It is mainly applied in scenarios such as photovoltaic power stations, wind farms, thermal power plants, and substations. Its core function is to monitor grid frequency and voltage parameters, and automatically cut off part of the load or perform islanding operations when the system experiences abnormalities, ensuring the safe and stable operation of the grid.