Toshiba GR200 Series - 2.35.3 Scheme for synchronism

6F2S1914 (0.49)
GRL200 (Soft 033 & 037)
- 478 -
2.35.3 Scheme for synchronism
VCHK has a measuring function, which checks the difference between a running voltage and
an incoming voltage. The measuring function checks phase angles, voltages, and frequencies.
The VCHK1 determines the synchronism based on the presence of voltage on both Bus-bar and
Line, as shown in Figure 2.35-4(a). The VCHK2 also determines the synchronism based on the
presence of voltage on both Line2 and Line, as shown in Figure 2.35-4(b).
VCHK-OVB or
VCHK-OVL
1
s
a. SYN1
V
B
V
L
V1
S = SYN1-Angle
VCHK-OVL2 or
VCHK-OVL
2
s
b. SYN2
V
L2
V
L
V2
S = SYN2-Angle
Figure 2.35-4 SYN1 and SYN2 characteristics
This function performs three checks: (1) checking voltage difference, (2) checking
frequency difference, and (3) checking phase difference. The following variables represent
algebraic expression used in these checking:
V
B
= Bus-bar voltage
V
L1
= Line voltage
V
L2
= Line2 voltage
ΔV1 = Voltage difference between Bus-bar and Line
ΔV2 = Voltage difference between Line2 and Line
fV
B
= frequency of V
B
fV
L
= frequency of V
L
fV
L2
= frequency of V
L2
f = slip cycle
Δf1 = frequency difference between Bus-bar and Line
Δf2 = frequency difference between Line2 and Line1
θ1= phase difference between V
B
and V
L
θ2 = phase difference between V
L2
and V
L
SYN1-dV = Voltage difference setting [SYN1-dV]
SYN2-dV = another voltage difference setting [SYN2-dV]
VCHK-OVB = voltage setting for Bus-bar [VCHK-OVB]
VCHK-OVL = voltage setting for Line [VCHK-OVL]
VCHK-OVL2 = voltage setting for Line2 [VCHK-OVL2]