Toshiba GR-200 Series Instruction Manual page 304

Phase angle difference
(iv)
The phase difference between the running voltage and the incoming voltage (θ) is
smaller than the SYN1 setting:
V B × V L cosθ ≥ 0
V B × V L sin ([SYN-Angle]) ≥ V B × V L sin θ
Notice and tips
(v)
If the frequency difference between the V L and the V B is shown very large, the
VCHK may fail to make the decision for the synchronism, although Off is set for the
[SYN-dfEN] to abandon checking the frequency difference. This is because; the
vector passes the [SYN1-Angle] zone very quickly. As a result, the VCHK may fail
to issue the permission command. To avoid the failure, the user has to set values for
settings [SYN-Angle] and [T_SYN] depending on the assumed frequency difference
(Δf):
where,
Tips: Cycles for the synchronism closure can be calculated:
Time length for getting a synchronism:
Check time for the synchronism:
⁡Setting⁡ [ T_SYN ] <
Equations rearrangements:
⁡Setting⁡ [ T_SYN ] <
Setting⁡[SYN-Angle]
∆f > ⁡
180° × Setting⁡[T_SYN]
Δf= Frequency-difference (or cycle-slip in Hertz)
Cycle⁡for⁡synchronism = 1 ∆f[Hz]
2 × Setting⁡[SYN-Angle]
⁡Time =
360°
2 × Setting⁡[SYN-Angle]
360°
Setting⁡[SYN-Angle]
180°
- 285 -
⁄
1
×
∆f[Hz]
1
×
∆f[Hz]
1
×
∆f[Hz]
6F2T0200 (0.15)
(2.25-1)
(2.25-2)
(2.25-3)
(2.25-4)
(2.25-5)
GRE200 (1,2)