VCB current zero phenomena modelled for circuit analysis

The post-are current phenomena that occur when interrupting high currents with vacuum circuit breakers (VCB´s) has been investigated. For this purpose, a simplified VCB model has been developed in Matlab´s SimPowerSystems. In the model the theory of Andrews-Varey is used to simulate the post-arc current. In this way, the post-arc current can be observed in any electrical circuit without having to elaborate the system equations. The results of the model is compared with experimental data, and high-resolution measurements around current zero are carried out with a test circuit for simulating short-line faults. For a legitimate comparison of the simulations with the measurements, the model parameters are held in a range of the values reported in the literature. The simulated results show good agreement with measurements. It will also be attempted to explain with the aid of this model a reignition observed in the measurements.