Bovenspanning

Bovenspanning is a term used in electrical engineering to describe a condition in which the voltage present in a system or component exceeds its nominal or rated voltage. It is a concern in power distribution, electrical equipment, and insulation design because excessive voltage can stress insulation and reduce safety margins.

Causes of bovenspanning include transient events such as switching operations, lightning surges, faults in the network, resonance phenomena, and sudden changes in generation or load. It can occur briefly as a surge or persist for a longer period during grid disturbances or abnormal operating conditions. Insulation coordination and proper protection are essential to manage these overvoltages.

Bovenspanning is typically categorized into transient or temporary overvoltage and sustained or persistent overvoltage. Transients are short-duration spikes caused by switching or lightning, while sustained overvoltage lasts longer and may result from abnormal grid voltage or open-circuit conditions in a network. The severity of an overvoltage is often described by the insulation level required for equipment to withstand it without damage.

Effects of bovenspanning can include accelerated aging of insulation, insulation breakdown, damage to electrical equipment such as transformers and motors, insulation degradation, excessive leakage currents, and nuisance tripping of protection devices. In sensitive systems, overvoltages can affect signal integrity and control electronics.

Protection and mitigation strategies include proper insulation design and margins, coordination of protective devices, and the use of surge protection devices (SPD), such as varistors and gas discharge tubes. Effective grounding, shielding, and circuit design practices help limit the impact of overvoltages. Standards and testing for insulation coordination and surge immunity guide the selection of components and protection schemes.