Wind Farm Protection
Automation, Lattes
Co-generation/Embedded Machines
AR?
81U/O
Frequency
27/59
Voltage
50/51N
47/46
59N
Residual Voltage
df/dt
ROCOF
dV
Voltage Vector Shift
O/C & E/F
NPS Voltage
NPS O/C
Schneider Electric - Marketing - Guilhen – Oct 2010
PES
system
Islanded load
fed unearthed
2
P341 Interconnection Protection
64
67N
46
50
51
50N
51N
59N
67
81O
81U
df
dt
dV
27
59
47
32
R,LF,O
Schneider Electric - Marketing - Guilhen – Oct 2010
3
33kV Transformer feeder extension to
windfarm - <10MVA,11kV collection
Schneider Electric - Marketing - Guilhen – Oct 2010
4
33kV ring network with embedded
generation, 2 wind farms with
collection voltage at 33 kV
Schneider Electric - Marketing - Guilhen – Oct 2010
5
Comprehensive Protection
Schneider Electric - Marketing - Guilhen – Oct 2010
6
Windfarm Protection Relays
Models
● P341 G59 Interconnection Protection
Relay
● P12x/P13x/P14x Feeder Protection (OC,
EF and AR)
● P92x Voltage/Frequency protection
Schneider Electric - Marketing - Guilhen – Oct 2010
7
ER G59 Protection Requirements
for Connection of Distributed
Generators
<5MW to Systems <20kV
Schneider Electric - Marketing - Guilhen – Oct 2010
8
MiCOM P341 Applications
G59 Protection Equipment
- MiCOM P341 Generator Protection Schneider Electric - Marketing - Guilhen – Oct 2010
9
MiCOM P341 Applications
G59 Protection Equipment
General Requirements Protective Equipment
● To inhibit connection of the generating equipment to the REC’s supply
unless all phases of the REC’s supply are energised and operating
within the agreed protection settings
● To disconnect the generator from the system when a system
abnormality occurs that results in an unacceptable deviation of the
voltage or frequency at the point of supply
- MiCOM P341 Generator Protection Schneider Electric - Marketing - Guilhen – Oct 2010
10
MiCOM P341 Applications
G59 Protection Equipment
General Requirements Protective Equipment
● To disconnect the generator from the REC’s system in the event of loss
of one or more phases of the REC’s supply to the installation
● To ensure that either the automatic disconnection of the generating
plant, or where there is component supervision of an installation, the
operation of an alarm with audible and visual indication, in the event of
a failure of any supplies to the protective equipment that would inhibit its
correct operation
- MiCOM P341 Generator Protection -
Schneider Electric - Marketing - Guilhen – Oct 2010
11
MiCOM P341 Applications
G59 Protection Equipment
Protection Requirements for Private Generator Operating in Parallel with
Electricity Board Network
Notes:
(1) Protection for generators
(2) Sensitive Relay
(3) Optional
(4) Application dependant
Protection required
Protection required for
Electricity Board Network
Permanent Parallel Operation
LV Generators
HV Generators
Export
No
Export
Small
<150kV
Medium
150-250kVA
Large
>250kVA
Under & Over Volt & Frequency
Loss of Mains (1)
Overcurrent
Earth Fault
Reverse Power
(2)
(3)
(3)
Directional Overcurrent (3)
Neutral Volt Displacement (4)
Parallel Limit Timer
Schneider Electric - Marketing - Guilhen – Oct 2010
12
MiCOM P341 Applications
G59 Protection Equipment
Protection Requirements for Private Generator Operating in Parallel
with Electricity Board Network
Notes:
(1) Protection for generators
(2) Sensitive Relay
(3) Optional
(4) Application dependant
Protection required
Protection required for
Electricity Board Network
Short Term ‘Test’ Parallel Operation (5 min max)
LV Generators
HV Generators
No
Export
Small
<150kV
Medium
150-250kVA
Large
>250kVA
Under & Over Voltage & Frequency
Loss of Mains (1)
Overcurrent
Earth Fault
Reverse Power
Directional Overcurrent (3)
Neutral Voltage Displacement (4)
Parallel Limit Timer
Schneider Electric - Marketing - Guilhen – Oct 2010
13
MiCOM P341 Applications
G59 Protection Equipment
Protective Equipment and Recommended Setting for LV Supply
Arrangements
Protection
Phases
Trip Setting
Total*
Tripping Time
Under Voltage
Over Voltage
All
-10% (Phase neutral)
0.5s
All
+10% (Phase neutral)
0.5s
Under Frequency
One
-6%
0.5s
Over frequency
One
+1%
0.5s
* The total tripping time includes any intrergration or timing period
of the protection relay as well as relay circuit-breaker operating time
For all other arrangements the settings of the relays should be
agreed with the REC
Schneider Electric - Marketing - Guilhen – Oct 2010
14
MiCOM P341 Applications
G59 Protection Equipment
Voltage Vector Shift Protection
An expression for a sinusoidal mains voltage waveform is generally given
by the following:
V = Vp sin (wt) or V = Vp sin  (t)
where
(t) = wt = 2ft
If the frequency is changing at constant rate Rf from a frequency fo then
the variation in the angle (t) is given by:
(t) = 2f dt, (F = Fo + Rf t)
which gives
(t) = 2{fo t + t Rf t/2}
and
V = V sin {2(fo + t Rf/2)t}
Hence the angle change (t) after time t is given by:
(t) = Rf t2
Schneider Electric - Marketing - Guilhen – Oct 2010
15
MiCOM P341 Applications
G59 Protection Equipment
Single phase line diagram showing generator parameters
jX
R
IL
E
VT
- MiCOM P341 Generator Protection -
Schneider Electric - Marketing - Guilhen – Oct 2010
16
MiCOM P341 Applications
G59 Protection Equipment
Vector Diagram Representing Steady State Condition
E
IL
VT
IL X
IL R
- MiCOM P341 Generator Protection -
Schneider Electric - Marketing - Guilhen – Oct 2010
17
MiCOM P341 Applications
G59 Protection Equipment
Transient voltage vector change  due to change in
load current IL
E
I LX
VT

IL
VT
 IL
I LR
 I LX”
- MiCOM P341 Generator Protection -
Schneider Electric - Marketing - Guilhen – Oct 2010
18
MiCOM P341 Applications
G59 Protection Equipment
df/dt
The rate of change of speed, or frequency, following a power disturbance
can be approximated by:
P.f
df/dt =
where
2GH
P = Change in power output between
synchronised and islanded operation
f = Rated frequency
G = Machine rate MVA
H = Inertia constant
Schneider Electric - Marketing - Guilhen – Oct 2010
19
MiCOM P341 Applications
G59 Protection Equipment
P341 df/dt calculation
df/dt =
Fn - f
n - 3 cycle
3 cycle
Two consecutive calculations must give a result above the setting
threshold before a trip decision can be initiated
- MiCOM P341 Generator Protection -
Schneider Electric - Marketing - Guilhen – Oct 2010
20
MiCOM P341 Applications
G59 Protection Equipment
df/dt+t: Time Delayed ROCOF
Start
t
Pick up cycles
Trip
f
Time delay
df/dt Setting
Schneider Electric - Marketing - Guilhen – Oct 2010
21