High Voltage Ride-Through (HVRT) is a key concept in power systems, particularly in the grid-connected integration of renewable energy generation (such as wind and photovoltaic power). It refers to the ability of grid-connected equipment (such as wind turbines and photovoltaic inverters) to maintain grid connection and maintain output within a specified timeframe (e.g., providing reactive power) when the grid voltage momentarily rises above the nominal value due to a fault (such as line fault removal or sudden shedding of a large load) or operational reasons.

During high-voltage ride-through (HVRT) scenarios, power systems experience sustained overvoltages (typically 1.1-1.5 times the rated voltage, lasting hundreds of milliseconds to several seconds), potentially accompanied by transient surges, harmonics, and oscillations. This places special demands on the selection of surge protective devices (SPDs). The key impact lies in the adaptability of key SPD parameters: the maximum continuous operating voltage (Uc) must be no less than the highest sustained voltage during HVRT. For example, in a 380V system, if the SPD needs to withstand 1.3 times the voltage (494V) for two seconds, its Uc must be no less than 494V (allow a 10%-20% margin for actual selection). Otherwise, the sustained overvoltage will prematurely turn on, leading to overheating and burnout. Furthermore, the SPD must withstand the combined stress of sustained overvoltage and transient surges. The voltage protection level (Up) must not exceed the withstand voltage of the protected equipment, and its current capacity and energy tolerance must be adapted to the combined energy surges. When choosing a type, voltage-limiting SPDs (such as high-Uc MOVs) are more suitable. Switching SPDs are prone to short-circuiting due to sustained overvoltage, and combination SPDs require component coordination. In different scenarios, SPDs for photovoltaic/wind power systems must match strict HVRT voltages and outdoor environments. Industrial power distribution systems prioritize equipment withstand voltage matching, while power grid transmission and transformation systems require high voltage resistance and immunity to environmental interference. Model selection should be based on standards such as IEC 61643-11 and GB/T 32900, balancing protection performance with system compatibility to avoid the risk of over-protection or failure.