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LECTURE VL

DOUBLE-ENERGY TRANSIENTS.

24. In a circuit in which energy can be stored in one form only,

the change in the stored energy which can take place as the result

of a change of the circuit conditions is an increase or decrease.
The transient can be separated from the permanent, condition, and
then always is the representation of a gradual decrease of energy.
Even if the stored energy after the change of circuit conditions is

greater than before, and during the transition period an increase
of energy occurs, the representation still is by a decrease of the
transient. This transient then is the difference between the energy
storage in the permanent condition and the energy storage during
the transition period.

If the law of proportionality between' current, voltage, magnetic
flux, etc., applies, the single-energy transient is a simple exponential
function:

ymy^fi_f (1)

where

l/o »» initial value of the transient, and
To « duration of the transient,

that is, the time which the transient voltage, current, etc., would
last if maintained at its initial value.

The duration T₀ is the ratio of the energy-storage coefficient
to the power-dissipation coefficient. Thus, if energy is stored by
the current i, as magnetic field,

r, -|, (2)

where L »• inductance «• coefficient of energy storage by the cur-
rent, r » resistance «• coefficient of power dissipation by the current.
If the energy is stored by the voltage e, as dielectric field, the
duration of the transient would be

3V -|, (3)



	LECTURE VL DOUBLE-ENERGY TRANSIENTS. 24. In a circuit in which energy can be stored in one form only, the change in the stored energy which can take place as the result of a change of the circuit conditions is an increase or decrease. The transient can be separated from the permanent, condition, and then always is the representation of a gradual decrease of energy. Even if the stored energy after the change of circuit conditions is greater than before, and during the transition period an increase of energy occurs, the representation still is by a decrease of the transient. This transient then is the difference between the energy storage in the permanent condition and the energy storage during the transition period. If the law of proportionality between' current, voltage, magnetic flux, etc., applies, the single-energy transient is a simple exponential function: f *ymy^fi_f* (1) where l/o »» initial value of the transient, and To « duration of the transient, that is, the time which the transient voltage, current, etc., would last if maintained at its initial value. The duration T₀ is the ratio of the energy-storage coefficient to the power-dissipation coefficient. Thus, if energy is stored by the current i, as magnetic field, r, -\|, (2) where L »• inductance «• coefficient of energy storage by the cur- rent, r » resistance «• coefficient of power dissipation by the current. If the energy is stored by the voltage e, as dielectric field, the duration of the transient would be 3V -\|, (3)