What causes voltage sags and swells?

Voltage sags and swells are primarily caused by fluctuations in load and faults within the electrical grid. When there are sudden changes in the demand for electricity, such as when large machinery starts up or shuts down, these fluctuations can lead to temporary drops (sags) or increases (swells) in voltage. Additionally, faults in the grid, like short circuits or equipment abnormalities, can disrupt the stable flow of electricity, resulting in these voltage anomalies.

Understanding these factors is essential for maintaining grid stability and ensuring that sensitive electronic equipment operates correctly, as excessive sags can lead to malfunctioning devices and swells can damage electrical systems. While distance from the power source and energy storage capacity can influence overall system performance, they do not directly cause sags and swells as effectively as load fluctuations and grid faults do.