Thytronic SME2-IS User Manual

49
SME2-IS - Manual - 06- 2021
FUNCTIONAL CHARACTERISTICS
• the breaker is open,
• the control of inputs V
1
and V
2
is ok,
• the two measured frequencies are in the permitted operating range (f
n
± f
RANGE
) for an adjustable
time of no less than t
STAB
,
• the difference, which denes the synchronous grid condition, between the two measured frequen-
cies is less than an adjustable threshold (df
-GRID
) for an adjustable time of no less than t
STAB
,
• the value of the two voltages is between a minimum threshold (V
min-SYNC
) and a maximum thresh-
old (V
max-SYNC
), both adjustable, for an adjustable time of no less than t
STAB
,
• the difference between the voltages V
1
and V
2
(with V
1
> V
2
) is less than an adjustable threshold
(dV12
-SYNC
), or the difference between V
2
and V
1
(with V
1
< V
2
) is less than an adjustable thresh-
old (dV21
-SYNC
), for an adjustable time no less than t
STAB
,
• the phase shift between V
1
and V
2
(with V
2
delayed relative to V
1
) is less than an adjustable thresh-
old (dp12
-SYNC
), or that between V
1
and V
2
(with V
1
delayed relative to V
2
) is less than an adjusta-
ble threshold (dp21
-SYNC
), for an adjustable time no less than t
STAB
,
• the above conditions persist for a time no less than the adjustable parameter (t
SYNC
).
If any of the above conditions does not obtain, the close command is not issued.
Asynchronous grids
For asynchronous grids (e.g. two separate distribution grids) the nal relay is operated (syn-
chronisation ok) once the comparison between the amplitudes and frequencies has been passed.
In particular, the difference between frequencies V
1
and V
2
(with f
1
> f
2
) is less than a congurable
threshold (df12
-SYNC
), or the difference between frequencies f
2
and f
1
(with f
1
< f
2
) is less than a
congurable threshold (df21
-SYNC
), for a congurable time of no less than t
STAB
.
The close command is issued in advance of the null phase shift condition, when the measured phase
shift is equal to the value calculated from the delays (relay + breaker close time) and frequency
difference between the two grids (slip frequency). In this way, the contacts close in a condition of
perfect synchronisation.
Control Functions
If the measurement is unstable, a report is issued, and if the difference between consecutive meas-
urements is greater than the adjustable value of parameter Rof>
SYNC
, execution of the parallel is
suspended. Setting Rof>
SYNC
= 0 disables stability control.
Operating logic
The synchronisation control sequence can be started by a pulse command generated by:
• automatic reclosing, internal to the protection relay or external, via a digital input programmed as
External reclosing trip,
• Digital input programmed as Breaker closing,
• a local command on the front keypad with the
(closing) button,
• a command over the comms interface.
When synchronisation control is requested, the congruence controls are run. If a non-permitted
state is detected, the Fault Sync report is issued and synchronisation control is not run.
If, on the other hand, the checks are positive, the synchrocheck sequence is initiated (signal
SYNC - IN PROGRESS.
If both voltages are incoming, the device checks whether the two grids are synchronous or asyn-
chronous by comparing the measured frequency difference to the threshold Df-
GRID
; if the differ-
ence is less than the threshold, the grids are deemed to be synchronous.
If the conditions are satised, the synchronisation function issues a close enable signal.
The duration of the enable signal can be adjusted by setting the parameter Operating mode to
PULSE and the duration (Minimum pulse duration) to the desired value for the nal relay
programmed in function 25; the parameters are available in the menu Set \ Outputs.
You can set the synchronisation attempt timeout (timeout
-SYNC
) in the menu Set \ Synchro
check - 25 \ Common configurations; if the conditions are not satised within this time, the se-
quence is suspended.
Regulation ranges for the synchronisation check function (25)
dv12
-SYNC
dv21
-SYNC
dp12
-SYNC
( V2 in delay relative of V1)
dp21
-SYNC
( V2 in andvance relative of V1)
{
{
V2
V1
V
Async grids
Sync grids
f
df
-GRID
dv21
-SYNC
(V2>V1)
df21
-SYNC
(f1<f2)
dv12
-SYNC
(V1>V2)
df12
-SYNC
(f1>f2)

Thytronic SME2-IS Specifications

General

Brand	Thytronic
Model	SME2-IS
Category	Security Sensors
Language	English