Impact Of Transient Overvoltage On Static Voltage Stabilizers

During power grid operation, lightning strikes, load surges, and switching operations can all generate transient high-voltage pulses on the lines. When such surge voltages impact the input of the static automatic voltage regulator, the device's regulation capability may be severely tested. The instantaneous voltage amplitude caused by surges often far exceeds the rated input range of the static stabilizer manufacturers, causing the voltage regulator circuit to be unable to complete the adjustment within the normal operating range.

The static voltage stabilizer for home is typically designed with a specific input voltage regulation range; for example, a device with a rated input of 220V may allow a fluctuation range of ±15%. However, the peak transient voltage generated by power grid surges can reach several kilovolts, with durations ranging from microseconds to milliseconds. Such short-term extreme voltages completely deviate from the linear regulation range of the regulator, and the internal voltage regulating elements will enter saturation or cutoff states under such severe impacts.

When a lightning strike occurs nearby, the voltage surge induced by the electromagnetic field on the power line can easily exceed the device's tolerance limit. Even though the static voltage stabilizer manufacturers is equipped with some overvoltage protection circuitry, when faced with surges of excessive amplitude, the internal varistor or TVS diode can only clamp the voltage to a certain level, and this clamping voltage may still be higher than the adjustable range of the voltage regulator circuit.