Transcript Slide 1

x
E
R
x
x
E
R
1:a
E
R/a 2
Load voltage (V) maintained
at 0.975 pu by varying tap
ratio a
Generator terminal voltage
maintained at 1.025 pu
Transmission line
0.01 + j0.05
j2.0
Load transformer
j0.08
j0.145
E
Generator transformer
0.01 + j0.05
V/a
Reflected load admittance on primary side of transformer = (0.75 – j 0.375)*(a * a)
0.985
+
S
V
amax
1
1
-----1+sT
0.001
s
0.01
-1
filter
deadband
0.01
amin
sign
discretiser
2.75
1.025 +
-
S
100
s
-2.75
Gen Terminal
Voltage
1
-----1+s
E
a
(tap)
Equilibrium
Large disturbance from Equilibrium
(spring breaks!)
PG0
wREF +
S
Controller + Actuator
w
Turbine
Gate
or
Valve
Position
PG
xe1
xg
xe2
X
xg
R
E1 d1
E2 d2
Pe1
PL1
PL2
P1, Q1
X
V1
d1
P2, Q2
R
V2
d2
Pe2
d
Speed/Rotor Angle
Generator
Mechanical Power
Turbine
Valve / Gate position
w
Governor
-
+
S
+
w_ref
S
KG
+
Pm0
(“Load Ref”)
GENERATOR
+
TURBINE/
GOVERNOR
Tie Line
NETWORK
(AREA 1)
GENERATOR
+
TURBINE/
GOVERNOR
ON
AGC
NETWORK
(AREA 2)
GENERATORS
+
TURBINES/
GOVERNORS
NOT ON
AGC
GENERATORS
+
TURBINES/
GOVERNORS
NOT ON
AGC
GENERATOR
+
TURBINE/
GOVERNOR
ON
AGC
DPmo1
DPmo2
Speed deviation
from nominal
k1/s
S
-
Speed deviation
from nominal
k2/s
+
+
B1
DP12
Measured Power Flow on Tie Line
B2
S
+
Main Generator
DC
AC
Controlled Rectifier
S
R
S
S
S
R
Main Generator
R
R
N
S
AC generator
Permanent
Magnet
Generator
Diode Bridge
(rotating)
Control Signals
From Regulator
R: Rotating Member
S: Stationary Member
Field
Winding
Stabilizing / Limiting Signals
+
+
S
Vref
Measured Terminal
Voltage
Controller
To
Thyristor
Bridge
Inverter
Rectifier
P, Q
P, Q
Idc
DC side
Va
a
Ia
Va
P>0
Q>0
0< a < 90
Ia
a
P<0
Q>0
90< a < 180
Va: phase a to neutral voltage
Ia : phase a current flowing into the converter
a: Delay Angle of Converter
P: Power Drawn by Converter
Q: Reactive power drawn by Converter
V
a=180
i
V
i
T1
ON
T2
ON
V
i
i
T2
a=90
a
V
Location 2
Location 1
Phase angular difference between the
two can be determined independently if
a common timing pulse is transmitted
to the locations simultaneously
(STATIC) DATA ACQUISITION
(executes every 2-4 seconds)
Remote Measurements
Voltage/ Power “Raw” Measurements
Status of Circuit Breakers
STATIC STATE ESTIMATION
(executes every 10s to 1 min)
Present Network /
Load/ Generation Configuration
(Operating Condition)
NORMAL STATE
STATIC / DYNAMIC SECURITY ANALYSIS
(executes every 1 – 10 mins)
OR
ALERT STATE
SECURITY CONSTRAINED
OPTIMAL POWER FLOW
(Executes every 10 – 30 mins)
REAL / REACTIVE
POWER SCHEDULE
CHANGES
Different Entities in a Deregulated Environment
Generator Companies
(Gencos)
Independent System Operator
(ISO)
Transmission Companies
(Transcos)
Distribution Companies
(Discos)
Retail Energy
Service Companies
(Rescos)
Customers
The Competition
Competitive
Generation Market
Many sellers vying to
sell to the customers
Competition
Transco
Monopoly Franchise
Disco
Monopoly Franchise
Monopoly
Competitive
Retail Power Market
Many retailers vying to
sell to the customers
Competition
Load Voltage (V) maintained
at 0.975 pu by varying tap
ratio
‘a’
Generator terminal voltage
Maintained at 1.025 pu
Transmission Line
0.01+j0.05
j2.0
E
j0.145
Load transformer
Generator Transformer 0.01+j0.05
j0.08
V
a
R
Reflected load admittance on primary side of transformer = (0.75-0.375)*(a*a)
ratio a
maintained at 1.025 pu
Transmission line
0.01 + j0.05
j2.0
Load transformer
j0.08
j0.145
E
Generator transformer
0.01 + j0.05
V/a
Reflected load admittance on primary side of transformer = (0.75 – j 0.375)*(a * a)
E
R
E, I
SECURE
NORMAL
Load tracking, economic dispatch
Reductions in reserve
margins
E, I
E, I
RESTORATIVE
Resynchronization
INSECURE
ALERT
Preventive Control
Violation of inequality
constraints
IN EXTREMIS
Cut losses,
protect equipment
E, I
SYSTEM NOT INTACT
E: Equality constraints,
System splitting
and / or
load loss
E, I
EMERGENCY
Heroic Action
A - Secure
SYSTEM INTACT
I: Inequality constraints,
-: Negation