11
2.7 DS1 Closing and Opening switching
behaviour
DS1 performs synchronous switching with the control system
constantly engaged with the upstream voltage reference. To
do this, the signal from a voltage divider (mandatory phase to
ground on phase R) is detected by its control system.
When an Open command or Close command is transmitted
to DS1, switching is performed by the control system using
network synchronization and not the command as the trigger.
In addition to this feature, a precise ability to coordinate three-
phase system movement and diode technology achieve very
performance-oriented switching capability without significant
inrush, AC voltage distortions or high frequency disturbance,
as well as precise zero crossing current cut-off.
Typical DS1 switching behaviour is outlined below, where main
circuit making and breaking possess the characteristics de-
scribed above since DS1 contains the diode that naturally
makes and breaks the current.
Figure 8. DS1 behaviour during a power test at 17.5kV 630A
Provided
by
Northeast
Power
Systems,
Inc.
(NEPSI)
