Page 390 - Renewable Energy Devices and System with Simulations in MATLAB and ANSYS

Microgrid for High-Surety Power: Architectures, Controls, Protection, and Demonstration 377

i(t) L
+ s
R s + DC bus
L s C capacitor
0 u(t) DC

L s C
DC/DC or DC/AC – – DC
module
DC bus of
super UPS

(a)

+ L s
DC bus
capacitor
L C DC
0 s
R s
L s C DC
DC/DC or DC/AC –
module

DC bus of
super UPS

(b)

+ L s
DC bus
capacitor
L
0 s C DC
R s L
– s C DC
DC/DC or DC/AC
module DC bus of
super UPS

(c)

FIGURE 14.22 Types of short-circuit fault: (a) Type I, short-circuit fault between positive bus and negative
bus; (b) Type II, short-circuit fault between positive bus and neutral bus; (c) Type III, short-circuit fault between
negative bus and neutral bus. (Continued)