Civil Engineering Reference
In-Depth Information
FIGURE 11-6
Battery charge converter for pv systems (DC to DC buck converter).
FIGURE 11-7
Charge converter operation during switch on-time and off-time.
T
T
Time on
Period
Duty ratio D
=
=
on
=
T
⋅
Switching Frequency
(11-5)
on
The charge converter operation during one complete cycle of the triggering
signal is shown in
Figure 11-7
.
During the on time, the switch is closed and
the circuit operates as on the left. The DC source charges the capacitor and
supplies power to the load via the inductor. During the off time, the switch
is open and the circuit operates as on the right. The power drawn from the
DC source is zero. However full load power is supplied by the energy stored
in the inductor and the capacitor, with the diode providing the return circuit.
Thus, the inductor and the capacitor provide short-time energy storage to
ride through the off period of the switch.
The simple analyses of this circuit is shown below. It illustrates the basic
method of analyzing all power electronic circuits.
The power electronic circuit analysis is based on the energy balance over
one period of the switching signal. That is as follows:
