Probabilistic model of fibrillation currents created by superposition of two shocking currents with different frequencies

Abstract

Abstract:The paper presents the probabilistic model of fibrillation currents containing two components with different frequencies. An analysis was conducted of the threat of ventricular fibrillation which occurs in consequence of the electric shock with the highest permissible contact shocking voltage of the network frequency (50 Hz), taking into account the threat caused by the second component of the voltage which has the frequency higher than the network frequency. The sample results of calculations apply to the probability of the ventricular fibrillation in case of a shock caused by the highest permissible contact shocking voltage, for the defined time of shock duration, without and with the participation of an additional voltage component with higher frequency. The formula has been presented for the calculation of the highest permissible contact shock voltages with taking into account the voltage component of the frequency higher than the network frequency. The results of calculations indicate that a considerable reduction of the highest permissible contact shock voltage is necessary in order to compensate for a growth of the ventricular fibrillation threat caused by the presence of an additional component with the frequency other the network frequency. This applies in particular to the long shock duration times and low frequencies (up to 500 Hz) of an additional component of the shocking voltage.

Shock safety modeling method for low-voltage electric devices

“…Values of random currents producing in humans such touch effects as the sensation of a current flowing, the inability of the person experiencing a touch to free themselves, and ventricular fibrillation, are dependent on [6,11,12]: the f frequency, the t touch duration time, the d touch path, and the m human body weight.…”