Why can lightning arresters protect electrical equipment from damage caused by lightning overvoltage?
Publish Time: 2024-09-19
Lightning arresters can protect electrical equipment from damage caused by lightning overvoltage. The main reasons are as follows:
Limiting overvoltage: Lightning arresters show high impedance under normal working voltage and have a suppressive effect on current. However, when lightning overvoltage invades, the lightning arrester will quickly change to low impedance, allowing the lightning current to be smoothly discharged into the ground, thereby limiting the amplitude of the overvoltage and preventing it from causing damage to electrical equipment.
Discharge characteristics: Lightning arresters usually use components such as nonlinear resistors or gas discharge gaps. These components can quickly discharge under the action of lightning overvoltage, guide the overvoltage energy to the ground, and protect the equipment from overvoltage shock.
Protective residual voltage: During the discharge process, the lightning arrester will limit the voltage at both ends to a certain level (i.e., protective residual voltage). This residual voltage value is much lower than the maximum overvoltage value that the electrical equipment can withstand, thereby ensuring the safety of the equipment.
Fast response: The lightning arrester has an extremely fast response speed and can respond to lightning overvoltage in a very short time (usually microseconds), quickly limit the overvoltage to a safe range, and prevent it from causing instantaneous shock to electrical equipment.
Continuous protection: Lightning arresters can not only provide protection when lightning strikes directly, but also play a protective role when lightning induced overvoltage and other indirect lightning effects occur, ensuring that electrical equipment can operate safely in various lightning environments.
Lightning arresters effectively limit the damage of lightning overvoltage to electrical equipment through their unique discharge characteristics, residual voltage protection, rapid response and continuous protection capabilities, ensuring the safe and stable operation of the power system.
