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电网结构、电源分布、负荷水平、电网规模、供电可靠性;大系统理论、分层决
< br>策、分层控制控制方式:局部控制;统一决策、集中控制;分散决策、分散控制;分
层决策、分层控制;
N-1
p>
标准、输电系统静态安全评估标准之一;
N-1
标准:系统中
1
个发电机组或
1
个电网设
备
(
线路、电缆、变压器
)
退出运行时,系统仍应能维
持运行。停电损失;系统运行涉及的备用主要有
负荷备用和事故备用。稳定控制
技术:就地分散型装置向区域分布式系统发展。防止区域
性频率崩溃的连锁切负荷
局部故障、保护及控制装置的拒动或误动、
不适当或不及时的手动措施、
导致一系列相
继故障或连锁开
断系统的充裕行、经济性和可靠性;
the
liberalization
of
electricity
market,
economical
benefits
,
the
grid
has
to
be
operated
with
maximized
transfers
physical
constrains;
outage,
partially
black-out,
complete
black-
out;
available
transmission
capacity(ATC)
突然损失发电机或线路:
sudden
loss
of
a
generator
or
transmission
line.
负荷突然增加或减少:
sudden
load
increases
or
decreases
短路和开关操作:
short
circuits
and
switching
operations.
三相和对地短路:
three-
phase
and
line-to-ground
faults
短路器:
circuit
breaker
暂态过电压和电流:
transient
overvoltages
and
currents
雷击:
lightning
strikes
电涌放电器:
surge
arrester
相量:
phasor
,通常用复数
phasors
瞬时功率:
instantaneous
power
特别地:
In
particular,
正弦电压或电流:
A
sinusoidal
voltage
or
current
at
constant
frequency
最大值:
maximum
value
有效值:
effective
value
平均值:
average
value
坐标系实轴:
real
axis
坐标系虚轴:
imaginary
axis
相量图:
phasor
diagram
for
无源元件:
passive
elements
电阻、电感、电容、电抗:
resistor,
inductor,
and
capacitor,
reactance,
感性、容性:
inductive,
capacitive
有功功率:
real
power
or
active
power
无功功率:
reactive
power
功率因数:
power
factor
功率因数角:
power
factor
angle
A
single-phase
source
delivers
100kW
to
a
load
operating
at
a
power
factor
of
0.8
lagging.
物理意义:
The
physical
significance
of
与…同相位:…
be
in
phase
with
…
Example
:
For
a
purely
resistive
load,
the
current
into
the
load
is
in
phase
with
the
load
voltage.
如式(
2.1
)所示:
As
indicated
by
(2.1),
……落后
(
超前
)
…多少相位:<
/p>
The
current
lags
p>
(
leads
…
t
he
voltage
by
90.
正弦稳态:
sinusoidal-
steady-state
让
a<
/p>
=
b
,得到:
Letting
a=b
gives
按照惯例(通常):
By
convention,
the
power
factor
cos(a-b)
is
positive.
时间区间:
a
time
interval
T.
Example:
The
total
energy
absorbed
by
a
load
during
a
time
interval
T
.
额
定值:
rating.
例:额定功率-
power
rating
;发电机额定功率-
power
rating
of
electric
generator
;
额定电压:
voltage
rating.
基尔霍夫电流(电压)方程:
Kirchhoff
’
s
current(voltage)
law
。
节点方程:
nodal
equations
导纳矩阵:
admittance
matrix
有
N
个节点电压构成的列相量:
column
vector
of
N
bus
voltages
对角元素:
diagonal
elements
非对角元:
off-diagonal
elements
自导纳:
self-admittance;
driving-
point
admittance
互导纳:
mutual
admittance;
transfer
admittance
美国
8.14
大停电:
The
US
blackout
on
14
August,
2003
…对…
将产生深远影响:
The
blackout
will
have
huge
technical
and
organizational
cons
equences
for
the
US
power
industry.
当地仅存的无功电源无法维持电压:
The
existing
local
reactive
power
sources
were
not
able
t
o
support
the
voltages.
切除线路:
trip(tripped)
the
lines.
The
isolated
part
suffered
from
low
voltage
and
a
severe
de
ficit
of
generation.
电力系统稳定是指…:
Power
system
stability
refers
to
the
ability
of
synchronous