Analysis of irregular current and voltage wave shapes found in industrial power engineering

THE industrial power application engineer is faced more and more with the problem of resolving the properties of irregular wave shapes of current and voltage. This is due to the ever-increasing use of current-limiting fuses, electronic switching devices, magnetic amplifiers, gaseous discharge tubes, lamps, etc. For the most part, the quantities to be resolved are: the current-time product (∫ idt), and the summation of the current squared-time product (∫ i2 dt). From the former are derived average, and from the latter root-mean-square values of current. Which of these two is desired in a particular problem will depend upon whether the effects being studied are responsive to the first power or to the second power of the current.