Internal Overvoltage

The internal overvoltage caused by the change of the internal operation mode of the power system is called internal overvoltage, and it is divided into three kinds: transient over-voltage, over voltage and over voltage.

The transient overvoltage is caused by the operation of the circuit breaker or the short circuit fault, which makes the power system experience a transient stability after the transition. Common are: 1. The effect of the no-load long line capacitance. In the operation of the power frequency power supply, because of the accumulation of capacitance effect, the voltage distribution along the line is different, and the terminal voltage is the highest. Asymmetric short circuit grounding. The voltage of B and C will increase when there is short circuit grounding fault in three-phase transmission line A. Load rejection overvoltage. When the transmission line of Shenzhen lighting project is forced to suddenly get rid of the load because of the fault, the over-voltage caused by the electric power supply has not been adjusted in time.

The operation voltage is due to circuit breaker operation or sudden short-circuit caused by the attenuation of voltage fast, short duration, are common among the idle line closing and reclosing over-voltage, over-voltage, cut off the resection of no-load no-load transformer overvoltage and arc grounding overvoltage.

Resonance overvoltage is an instantaneous voltage in the power system, such as inductance, capacitance and other energy storage components in some wiring mode Shenzhen lighting design and power supply frequency resonance caused by the. According to the causes, it can be divided into linear resonance overvoltage, ferroresonance overvoltage and resonance overvoltage. The amplitude of the internal overvoltage is generally not more than 3 - to 3.5 times of the rated voltage of the power grid. This is because it has a certain margin than the insulation strength of the large production line in the design.