Phần 7 KHÓA ĐÀO TẠO TÍNH TOÁN ỔN ĐỊNH VÀ ỨNG DỤNG TRÊN PHẦN MỀM PSSE CHO KỸ SƯ HỆ THỐNG ĐIỆN (Nguyên tắc mô phỏng Ổn định động và các thư viện mô hình mô phỏng trên Phần mềm PSSE)

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A Division of Global Power
POWER SYSTEM STABILITY CALCULATION TRAINING
D3
DiSiltiPiilPt2
D
ay
3
-
D
ynam
i
c
Si
mu
l
a
ti
on
P
r
i
nc
i
p
l
es
P
ar
t

2
July 8, 2013Prepared by: Mohamed El Chehaly
eBook for You
OUTLINE
2
OUTLINE
• Classification of Variables
• Dynamic Simulation Sequence
• Overview of Simulation Procedure
eBook for You
3
CLASSIFICATION OF
VARIABLES
VARIABLES
eBook for You
General Classification
4
CLASSIFICATION OF VARIABLES
General

Classification
 Constants: Parameters that do not vary
 State variables: Variables for which
instantaneous values are determined by
differential equations
differential

equations
 Algebraic variables: Variables for which

values can be determined if the values of all
values

can

be

determined

if

the

values

of

all

state variables, constants, and input
variables are
g
iven
g
 Input variables: Quantities for which values
are s
p
ecified at an
y
instant b

y
lo
g
ic outside
pyyg
the dynamic simulation
eBook for You
5
CLASSIFICATION OF VARIABLES
Exam
p
le of Power S
y
stem D
y
namic
pyy
Simulations
eBook for You
Exam
p
le of Power S
y
stem D
y
namic
6
CLASSIFICATION OF VARIABLES
pyy
Simulations

 Differential equations:
nem
n
DPP
dt
d
H




2
n
s
ync
dt
d
dt




 Constants
 Inertia: H
dt
 Damping: D
 Synchronous speed: ω
sync
= 1 p.u.
eBook for You

Exam
p
le of Power S
y
stem D
y
namic
7
CLASSIFICATION OF VARIABLES
pyy
Simulations

Sequence of Calculation:

Sequence

of

Calculation:
1. Calculate V
b




E
1
1
'
2

Calculate
I




















jXRjX
jB
jXR
e
jX
E
V
b

1
'
1
/
'
'
2
.
Calculate

I
gen
'
'
jX
VE
I
b
gen


3. Calculate P
gen
jX

cos'
gengen
I
EP


eBook for You
Exam
p
le of Power S
y
stem D
y
namic
8
CLASSIFICATION OF VARIABLES
pyy
Simulations

Sequence of Calculation:

Sequence

of

Calculation:
4. Calculate time derivatives

nem
n
HDPP
dt
d


 2/

n
dt
d



eBook for You
Dynamic Simulation Arrays
9
CLASSIFICATION OF VARIABLES
Dynamic

Simulation

Arrays
 Constants
eBook for You
Dynamic Simulation Arrays
10
CLASSIFICATION OF VARIABLES
Dynamic

Simulation

Arrays
 State Variables

Input Variables

Input

Variables
eBook for You
Dynamic Simulation Arrays
11
CLASSIFICATION OF VARIABLES
Dynamic

Simulation

Arrays
 Algebraic Variables
eBook for You
Dynamic Simulation Arrays
12
CLASSIFICATION OF VARIABLES
Dynamic

Simulation

Arrays
 Algebraic Variables
eBook for You
Dynamic Simulation Arrays
13
CLASSIFICATION OF VARIABLES
Dynamic

Simulation

Arrays
 Internal Arrays
eBook for You
Data Space Allocation
14
CLASSIFICATION OF VARIABLES
Data

Space

Allocation
 CON, VAR, STATE, ICON and DSTATE are
allocated to equipment models on a first-
come, first-served basis.
PELEC (I)PMECH (I) STATE (L)
DSTATE (L)

nem
n
HDPP
dt
d


 2/
DSTATE (L+1)
n
dt
d




CON
(
J
)
CON (J+1)
()
eBook for You
Data Space Allocation
15
CLASSIFICATION OF VARIABLES
Data

Space

Allocation

Th PSS®E di f th l t l

Th
e
PSS®E
co
di
ng
f
or
th
e

l
as
t
examp
l
e:
DSTATE(L) (PMECH(I)
PELEC(I)
DSTATE(L)
=
(PMECH(I)
-
PELEC(I)
-
CON(J+1)*STATE(L))/(2*CON(J))
DSTATE(L+1) STATE(L)
DSTATE(L+1)
=
STATE(L)
SPEED(I) = STATE(L)
G()S ( )
AN
G
LE
(
I
)
=
S
TATE

(
L+1
)
eBook for You
Data Space Allocation
16
CLASSIFICATION OF VARIABLES
Data

Space

Allocation
eBook for You
17
DYNAMIC SIMULATION
SEQUENCE
SEQUENCE
eBook for You
Overall Flow Chart
18
DYNAMIC SIMULATION SEQUENCE
Overall

Flow

Chart
 Logic required to inform PSS®E of the
differential equations is provided by two
libraries of subroutines:
 Handling models that involve state variables and

differential equations
differential

equations
 Handling models that involve only algebraic
relationshi
p
s between in
p
ut and out
p
ut si
g
nals
pppg
without reference to differential equations
 4 subroutines: TBLCNC, TBLCNT, CONEC
and CONET
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Dynamic Simulation Basic Flow
19
DYNAMIC SIMULATION SEQUENCE
Dynamic

Simulation

Basic

Flow
eBook for You

Dynamic Simulation Basic Flow
20
DYNAMIC SIMULATION SEQUENCE
Dynamic

Simulation

Basic

Flow
eBook for You
Subroutines TBLCNC and CONEC
21
DYNAMIC SIMULATION SEQUENCE
Subroutines

TBLCNC

and

CONEC
 Responsible for equipment models
involving state variables and differential
involving

state

variables

and

differential

equations

Responsible for time derivative of every

Responsible

for

time

derivative

of

every

state variable

Responsible for calculating the values of

Responsible

for

calculating

the

values

of

all algebraic values of the state variable
time derivatives
 TBLCNC: responsible for machines and
their control systems
 CONEC: responsible for all other models
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Subroutines TBLCNT and CONET
22
DYNAMIC SIMULATION SEQUENCE
Subroutines

TBLCNT

and

CONET
 Responsible for equipment models in
which there is a purely algebraic
which

there

is

a

purely

algebraic

relationship between the voltage at a bus
and the current drawn by a device
and

the

current

drawn

by

a

device
 Responsible for equipment models for
which in
p
ut or out
p
ut is a
q
uantit
y

ppqy
determined solely by network quantities,
such as relays and monitoring models
 Principle equipment: shunt load devices
(reactors), relays and meters
eBook for You
Subroutines TBLCNT and CONET
23
DYNAMIC SIMULATION SEQUENCE
Subroutines

TBLCNT

and

CONET
 Responsible for equipment models in
which there is a purely algebraic
which

there

is

a

purely

algebraic

relationship between the voltage at a bus
and the current drawn by a device
and

the

current

drawn

by

a

device
 Responsible for equipment models for
which in
p
ut or out
p
ut is a
q
uantit
y

ppqy
determined solely by network quantities,
such as relays and monitoring models
 Principle equipment: shunt load devices
(reactors), relays and meters

eBook for You
Dynamic Simulation Control Flags
24
DYNAMIC SIMULATION SEQUENCE
Dynamic

Simulation

Control

Flags

MODE

MODE
 1: Initialization. Calculate initial condition values of
all state and algebraic variables
 2: The model must make all computations needed
to place time derivatives into the DSTATE array
(stabilizers excitation limiters )
(stabilizers
,
excitation

limiters
,…
)
 3: Computation of output values of generator
source currents, exciter field voltages, turbine
mechanical powers, stabilizer outputs, excitation

limiter outputs

4: Apply special calculations in initialization of

4:

Apply

special

calculations

in

initialization

of

induction motor and dc transmission models
eBook for You
Dynamic Simulation Control Flags
25
DYNAMIC SIMULATION SEQUENCE
Dynamic

Simulation

Control

Flags


MODE

MODE
 1: Initialization. Calculate initial condition values of
all state and algebraic variables
 2: The model must make all computations needed
to place time derivatives into the DSTATE array
(stabilizers excitation limiters )
(stabilizers
,
excitation

limiters
,…
)
 3: Computation of output values of generator
source currents, exciter field voltages, turbine
mechanical powers, stabilizer outputs, excitation
limiter outputs

4: Apply special calculations in initialization of

4:

Apply

special

calculations

in

initialization

of

induction motor and dc transmission models
eBook for You