Wind Farm Protection

1
Wind Farm Protection

• Automation, Lattes

2
Co-generation/Embedded Machines
PES system
PES system
AR?
81U/O
27/59
Islanded load fed unearthed
59N
df/dt
dV?
3
P341 Interconnection Protection
64
67N
50 51
50N 51N
46
59N
67
df dt
81O 81U
27 59
dV
47
32
R,LF,O
4
33kV Transformer feeder extension to windfarm -
lt10MVA,11kV collection
5
33kV ring network with embedded generation, 2
wind farms with collection voltage at 33 kV
6
Comprehensive Protection
7
Windfarm Protection Relays

• Models
• P341 G59 Interconnection Protection Relay
• P12x/P13x/P14x Feeder Protection (OC, EF and AR)
• P92x Voltage/Frequency protection

8
ER G59 Protection Requirements for Connection of
Distributed Generatorslt5MW to Systems lt20kV
9
MiCOM P341 ApplicationsG59 Protection Equipment
- MiCOM P341 Generator Protection -
10
MiCOM P341 ApplicationsG59 Protection Equipment
General Requirements Protective Equipment

• To inhibit connection of the generating equipment
  to the RECs supply unless all phases of the
  RECs 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 -
11
MiCOM P341 ApplicationsG59 Protection Equipment
General Requirements Protective Equipment

• To disconnect the generator from the RECs system
  in the event of loss of one or more phases of the
  RECs 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 -
12
MiCOM P341 ApplicationsG59 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
Permanent Parallel Operation
LV Generators
HV Generators
Protection required
Small lt150kV
Medium 150-250kVA
Large gt250kVA
Export
No Export

• Protection required for
• Electricity Board Network
• Under Over Volt Frequency
• Loss of Mains (1)
• Overcurrent
• Earth Fault
• Reverse Power
• Directional Overcurrent (3)
• Neutral Volt Displacement (4)
• Parallel Limit Timer

(2)
(3)
(3)
13
MiCOM P341 ApplicationsG59 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
Short Term Test Parallel Operation (5 min max)

• Protection required for
• Electricity Board Network
• Under Over Voltage Frequency
• Loss of Mains (1)
• Overcurrent
• Earth Fault
• Reverse Power
• Directional Overcurrent (3)
• Neutral Voltage Displacement (4)
• Parallel Limit Timer

LV Generators
HV Generators
Protection required
Small lt150kV
Medium 150-250kVA
Large gt250kVA
No Export
14
MiCOM P341 ApplicationsG59 Protection Equipment
Protective Equipment and Recommended Setting for
LV Supply Arrangements

• Protection
• Under Voltage
• Over Voltage
• Under Frequency
• Over frequency

Phases All All One One
Trip Setting -10 (Phase neutral) 10
(Phase neutral) -6 1
Total Tripping Time 0.5s 0.5s 0.5s 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
15
MiCOM P341 ApplicationsG59 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

16
MiCOM P341 ApplicationsG59 Protection Equipment
Single phase line diagram showing generator
parameters
jX
R
I
L
E
V
T
- MiCOM P341 Generator Protection -
17
MiCOM P341 ApplicationsG59 Protection Equipment
Vector Diagram Representing Steady State Condition
E
I X
L
V
I R
T
I
L
L
- MiCOM P341 Generator Protection -
18
MiCOM P341 ApplicationsG59 Protection Equipment
Transient voltage vector change ? due to change
in load current ?IL
- MiCOM P341 Generator Protection -
19
MiCOM P341 ApplicationsG59 Protection Equipment
df/dt

• The rate of change of speed, or frequency,
  following a power disturbance can be approximated
  by
• df/dt
• where P Change in power output between
  synchronised and islanded operation
• f Rated frequency
• G Machine rate MVA
• H Inertia constant

?P.f 2GH
20
MiCOM P341 ApplicationsG59 Protection Equipment
P341 df/dt calculation
F - f 3 cycle
n n - 3 cycle

• df/dt
• Two consecutive calculations must give a result
  above the setting threshold before a trip
  decision can be initiated

- MiCOM P341 Generator Protection -
21
df/dtt Time Delayed ROCOF
MiCOM P341 ApplicationsG59 Protection Equipment
t
Start
Pick up cycles
Trip
f
Time delay
df/dt Setting
22
(No Transcript)