No abstract

The vulnerability of microcontroller system against high-altitude electromagnetic pulse (HEMP) is taken as an illustration to demonstrate the assessment methodology based on Bayesian networks (BN). The complete procedure is performed by two steps: the qualitative and the quantitative. The first step focuses on the analysis of three classes of properties, the electromagnetic environment, system function/structure, and their interactions. The primary BN model is built at the end of the first step. The second step investigates the BN nodes and branches one by one, which further implemented through two stages, i.e., the data acquisition and data fusion. The susceptibilities of devises are examined with the pulsed current injection. The responses of the transmission lines to HEMP are computed using the field-line coupling model. Comparing the probability density functions of the electromagnetic stresses and strengths produces the failure probabilities of the interface components. Through two-step analysis, the critical elements and coupling paths are identified and highlighted. After neglecting those unimportant factors, many BN nodes and branches are deleted. Thus, the complexity of assessment is reduced. By assigning the probability values to the simplified BN model, the system failure probability is calculated, which characterizes the system vulnerability against HEMP environment. The illustration validates the rationality and flexibility of the BN assessment methodology.

In order to study the strong electromagnetic pulse effect of critically vulnerable equipment in power systems and evaluate the survivability under high-altitude electromagnetic pulses, it is necessary to study the characteristics of the transient response of metal oxide arresters to the high-altitude electromagnetic pulse by experiment. In this paper, an experimental platform for high-altitude electromagnetic pulse conduction current injection for a typical 10 kV metal oxide arrester was set up, and the key parameters such as peak value of overshoot voltage, peak value of residual voltage, action voltage and response time were obtained by the experiment. The results show that: the action voltage of this type of metal oxide arrester is 3.53 times higher than that of its rated voltage; the peak value of overshoot voltage is 2.19 times that of the peak value of residual voltage under lightning impulse current; the peak value of residual voltage is 1.57 times that under lightning impulse; and the response time varies little with the electromagnetic pulse conduction current amplitude, averaging 46.86 nanoseconds under a high-altitude electromagnetic pulse conduction environment.

No abstract

With the final objective to assure equivalence between radiated and conducted immunity testing to intense electromagnetic pulses, in this work a circuit model of a typical pulsed current injection (PCI) test setup is derived, implemented in SPICE, and validated by measurement. By virtue of such a model, the parameters of the discharge circuit of the pulse generator can be adjusted to compensate the waveform distortion introduced by the injection probe. As proven by an example, the proposed method allows reproducing at the input of the equipment under test a transient disturbance with expected characteristics (i.e., amplitude, rise time, and pulse width)