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ELEMENTARY LECTURES ON ELECTRIC

DISCHARGES, WAVES AND IMPULSES,
AND OTHER TRANSIENTS.

LECTURE I.
NATURE AND ORIGIN OF TRANSIENTS.

i. Electrical engineering deals with-electric energy and its
flow, that is, electric power. Two classes of phenomena are met:
permanent and transient phenomena. To illustrate: Let 0 in
Fig. 1 be a direct-current generator, which over a circuit A con-
nects to a load L, as a number of lamps, etc. In the generator
Gj the line A, and the load L, a current i flows, and voltages e

O( o

Fig. 1.

exist, which are constant, or permanent, as long as the conditions
of the circuit remain the same. If we connect in some more
lights, or disconnect some of the load, we get a different current
i', and possibly different voltages e^f; but again i^f and e^f are per-
manent, that is, remain the same as long as the circuit remains
unchanged.

Let, however, in Fig. 2, a direct-current generator 0 be connected
to an electrostatic condenser C, Before the switch 8 is closed, and
therefore alw> in the moment of closing the switch, no current flows
In the line A. Immediately after the switch $ is closed, current
begins to flow over line A into the condenser (7, charging this
condenser up to the voltage given by the generator* When the



	ELEMENTARY LECTURES ON ELECTRIC DISCHARGES, WAVES AND IMPULSES, AND OTHER TRANSIENTS. LECTURE I. NATURE AND ORIGIN OF TRANSIENTS. i. Electrical engineering deals with-electric energy and its flow, that is, electric power. Two classes of phenomena are met: permanent and transient phenomena. To illustrate: Let 0 in Fig. 1 be a direct-current generator, which over a circuit A con- nects to a load L, as a number of lamps, etc. In the generator Gj the line A, and the load L, a current i flows, and voltages e

	O( o
	A

	Fig. 1. exist, which are constant, or permanent, as long as the conditions of the circuit remain the same. If we connect in some more lights, or disconnect some of the load, we get a different current i', and possibly different voltages e^f; but again i^f and e^f are per- manent, that is, remain the same as long as the circuit remains unchanged. Let, however, in Fig. 2, a direct-current generator 0 be connected to an electrostatic condenser C, Before the switch 8 is closed, and therefore alw> in the moment of closing the switch, no current flows In the line A. Immediately after the switch $ is closed, current begins to flow over line A into the condenser (7, charging this condenser up to the voltage given by the generator* When the 1