Index
A
Active power-frequency control, 87–88
AC-to-AC converters (cycloconverters), 104
AC-to-DC converters, 96, See also Rectifiers
AC-to-DC-to-AC converter, 240, 245
Adiabatic storage systems, 167
Admittance, per-unit and percent, 68
Africa, 9
Air circuit breakers, 81, 82, 83, 85
Alternating current (AC) energy storage, 156
Alternating current (AC) machines
asynchronous, 46–51, See also Induction generators
synchronous, 39–46, See also Synchronous generators
Alternating current (AC) power transmission, 61–62
American Wind Energy Association (AWEA), 1
Anemometer, 122
Angular velocity, 29
synchronous machine, 39–40, 41
Asian wind energy markets, 7–8
Asymmetrical faults, 70, 70–71
Asynchronous generators, 46–51, See also Induction generators
Australia, 8
Austria, 6
Automatic voltage regulator (AVR), 43, 143, 169, 215
Average wind speed-based pitch angle control, 205
B
Back emf, 56
“Backup” generation capacity, 149
Ball-bearing loss, 130
Balun transformer, 59
Base current and impedance, 66
Base of wind turbine, 20
Battery energy storage systems (BESSs), 159–161
hybrid storage systems, 168
Battery power, 150
DC-to-DC conversion, 102
Betz coefficient, 28
Blade pitch angle, 28, 118, See also Pitch control
Bonneville Power Administration (BPA), 169
Boost converter, 102
Brake, 20
Braking chopper method, 245
Braking resistor (BR), 213, 220–221
comparison of stabilization methods, 223–231
Brazil, 8
C
ferroresonance, 148
Capacitance
energy storage systems, 161–162
ferroresonance, 148
induction generator requirement, 50
STATCOM (static synchronous compensator), 219
supercapacitor system, 199, See also Supercapacitor energy storage systems
transmission line characterization (shunt capacitance), 63
Capacitors
DC applications, 162
effective series resistance, 161
electric double-layer (EDLC), 168, 246, 250, 251
energy storage systems, 161–163, See also Supercapacitor energy storage systems
hybrid energy storage systems, 168
hypercapacitors and ultracapacitors, 162–163
switched reluctance generator system, 253
Capacity credit, 151
Ceramic hypercapacitors, 162–163
China, 7
Chopper, 100–103, 157, 201–202, 217–218, 240–241, See also DC-to-DC converter
Circuit breakers, 37, 68, 71, 80–87
maximum short-circuit current, 82
residual-current devices, 84
supplemental circuit protectors, 83
common trip breakers, 84
medium-voltage, 85
sulfur hexafluoride, 82, 85, 86
thermal magnetic, 84
unsuccessful reclosure fault model for comparing stabilization methods, 222–227
Coefficient of performance (Cp), 28
Cold Cathode Fluorescent Lamp (CCFL) inverter, 57
Combined heat and power (CHP), 150
Common trip breakers, 84
Communications and external control systems, 106, 144
Compensators, 39, 89, 113, 114
STATCOM (static synchronous compensator), 213, 218–219, 223
Composite materials, 19
Compressed air energy storage (CAES), 150, 167
hybrid storage systems, 168
Constant power control, DFIG wind turbines with supercapacitor energy storage system, 198–202
Controller systems for wind turbines, 20, 198
Conventional power generation, 60–61
Converters, See Power electronics; specific types
Cost issues, 3
comparing stabilization methods, 228, 230
power converters, 120
Critical clearing time, 75
Cryostat, 157
Cuk converter, 103
Current, 66
Current source converter (CSC), 157
Current source inverter (CSI), 107–110
Current transformers, 58
Cut-in speed, 30
Cycloconverters, 104
D
DC bus microgrid system, 193–196
DC offset, 90
DC-to-AC converters (inverters), 96–100, See also Inverters
DC-to-DC converter, 100–103, 122–123, 157, 170, 201–202, 217–218, 228, 240–241, 245, 246
Dead tank circuit breakers, 86
Dewar, 157
Diabatic storage systems, 167
Diesel-governor model, 169f Diodes
LEDs, 102
power, p5, 96
rectifiers, 96
Direct current (DC) capacitor applications, 162
Direct current (DC) circuit breakers, 83
Direct current (DC) machines, 37–39
Direct current (DC) power transmission, 61–62
Direct drives, 20
Direct-drive synchronous generators, 113, 117
Doubly fed induction generators (DFIGs), 113, 118, 235–236
constant power control and supercapacitor energy storage, 198–203
fault ride-through capability, 235–240
grid-side converter control, 238–240
rotor-side converter control, 237–238
power electronics, 236
Downwind horizontal axis wind turbine, 22
Drag-type vertical axis wind turbine, 21
Duty cycle
DC-to-DC chopper, 100, 122, 171–172
pulse width modulation (PWM), 105
Dynamic voltage restorer (DVR), 162
E
Effective series resistance (ESR), 161
Egypt, 9
Electrical power systems, 59–60, See also Power system analysis
basic elements, 60
conventional power generation, 60–61
faults in, See Faults
stability, See Power system stability
Electric double-layer capacitor (EDLC), 168, 246, 250, 251
Electricity supply and demand flows, 142, 147
Electric machines, 37, See also specific types
AC machines, 39
AC machines, asynchronous, 46–51, See also Induction motors
AC machines, synchronous, 39–46, See also Synchronous generators
synchronous reluctance machines, 51–52
Electric power distribution, 63–64
Electric power transmission, 61–63
conductors, 62
high-voltage circuit breakers, 85
insulators, 62
subtransmission circuits, 63–64
transformers and, 53, 59, See also Transformers
Electric utility grid code requirements, 143–149
Electromagnetic transients program (EMTP), 222
Enercon E126, 18
Energy storage systems, 150, 155
advanced capacitors, 161–163, 198–203, See also Supercapacitor energy storage systems
comparisons, 168
flywheel systems, 150, 163–164, 189–198, See also Flywheel energy storage systems
hybrid, 168
permanent magnet synchronous generator fault ride-through and, 246, 248–251
potential benefits, 156
power-energy ranges, 156
pumped hydroelectric, 150, 165
SMES, 156–159, 168–189, 207–208, See also Superconducting magnetic energy storage
thermoelectric, 167
Environmental concerns, 3
European Wind Energy Association (EWEA), 5
European wind energy market, 4–6, 149
Excitation controller, fault ride-through capability, 244
F
Faraday’s law of induction, 54
Fault analysis, 65
Fault current limiters, 213–214, 221
Fault protection, 68, 71, 80–87, See also Fault ride-through (FRT) capability
circuit breakers, 80–86, See also Circuit breakers
high-voltage ride-through (HVRT), 144
low-voltage ride-through (LVRT), 144, 235
residual-current devices, 84–86, 86
resonance conditions, 148
superconducting fault current limiters, 213–214
supplemental circuit protectors, 83
transient stability enhancement, See Transient stability enhancement solutions
Fault ride-through (FRT) capability, 142, 235
doubly fed induction generator systems, 235–240
grid code requirements, 144–146
low-voltage ride-through (LVRT), 144, 235, 245, 249–250
permanent magnet synchronous generator, 245–251
switched reluctance generator system, 251–254
wound field synchronous generator systems, 240–245
persistent, 69
stabilization solutions, See Stabilization methods
symmetrical and asymmetrical, 69–71
transient, 69, 213, See also Transient stability enhancement solutions
unsuccessful reclosure model for comparing stabilization methods, 222–227
Ferroresonance, 148
Field-effect transistors (FETs), 102
Field-oriented vector control, 194–195
First-swing instability, 75
Fixed-speed wind energy conversion systems, 113–114
stabilization solutions, 213–231, See also Transient stability enhancement solutions
Flexible AC transmission systems (FACTS), 156, 157
battery energy storage integration, 161
voltage source converter/inverter and, 219
Flexible power system design, 149–150
Flux density, 126
Flywheel energy storage systems, 150, 163–164, 189–198
advantages, 191
hybrid storage systems, 168
stability consideration, 197–198
Forecasting wind power variability, 142
Fossil fuel-based power generation, 60–61
grid code requirements, 143
potential SMES applications, 158, 169
Frequency operating range requirements, 143
Frequency stability, 76–77, 148
power quality issues, 90, See also Power quality
power system frequency calculation, 173
SMES and, 172–178, 182–188, 207
wind speed variations and, 142, 155
Fuel cells, 150
Furling (cutoff) speed, 30
polyswitch (polyfuse), 87
G
Gas circuit breakers, 82, 85, 86
Gate turn-off (GTO) devices, 109, 169, 219
Generalized predictive control (GPC), 203–204
Generator bus, 65
Generators, See Induction generators; Synchronous generators; Wind generators
German grid code requirements, 145–147
Global Wind Energy Council (GWEC), 1
Governor (GOV) control system, 43, 169, 215
Greece, 6
Grid code requirements, 143–149
Grid integration issues, 141
auto reclosure, 148
capacity credit of wind energy, 151
codes and connection requirements, 143–149
fault ride-through capability, 144–146
ferroresonance, 148
induction generator connections, 50–51
managing wind power variability, 142
power quality fluctuations due to random wind speed variations, 142
power storage, 150
power systems design and operation, 149–150
transient stability and power quality problems, 141–142
Grid power system, 42
Grid-side converter (GSC) control, 200–201, 235, 237, 238–240, 244–245
Ground fault, 68
Ground fault circuit interrupter (GFCI) breakers, 80–86
Ground fault interrupter (GFI), 87
H
pulse width modulation, 107
reduction approaches, 219
High-temperature superconductor devices, 158
High-voltage circuit breakers, 85–86
High-voltage direct current (HVDC) link terminals, 78
High-voltage ride-through (HVRT), 144
Horizontal axis wind turbine (HAWT), 22–23
Hum, 58
Hybrid energy storage systems, 168
Hydroturbine generators, 40
I
Ideal power equation for transformers, 55–56
Ideal turbine power output, 25–28
India, 7
advantageous features, 117
DFIGs, See Doubly fed induction generators
efficiency calculation issues, 123–124, 127–130
equivalent circuit, 124f
fault ride-through, See Fault ride-through capability
flywheel energy storage, 189–193, See also Flywheel energy storage systems
grid and stand-alone connections, 50–51
parameters (table), 51
reactive power requirements, 151, See also Reactive power control
required capacitance, 50
stabilization solutions, See Stabilization methods
transient stability and power quality problems, 213
volt/hertz speed control, 194–195
wind generators, 113, 115, 117–118, 123, 151, 213, See also Wind generators
Induction motors, 37, 39, 46–51, See also Induction motors
synchronous motor difference, 47–48
Infinite bus concept, 89
Instrument transformers, 58
Insulated gate bipolar transistors (IGBTs), 96, 109, 170–172, 201, 217–218, 223–231, 236, 240, 253
Insulators, 62
Interharmonics, 90
Cold Cathode Fluorescent Lamp (CCFL), 57
voltage source, 117, 218–219, See also Voltage source converter
Iran, 9
Ireland, 149
Isothermal storage, 167
J
K
L
Large-disturbance rotor angle stability, 75
Large-disturbance voltage stability, 79
Large-scale wind turbines, 24
Lead acid batteries, 160
Leakage transformers, 57
Lenz’s law, 56
Lift-type vertical axis wind turbine, 22
Light-emitting diode (LED), 102
Linear programming, 65
Lithium-ion batteries, 160
Live tank circuit breakers, 86
Load bus, 65
Load flow study, 65
Load-frequency control, 88
Long-term voltage stability, 80
Loss analysis, See Wind generators, total efficiency calculation; specific losses
Low-pass filter (LPF), 172
fault ride-through capability for wound field synchronous generator, 242
flywheel energy storage system control, 196
time constant adjustments for superconducting magnetic energy storage systems, 178, 182–188, 208
Low-temperature superconductor devices (LTSs), 158
Low-voltage circuit breakers, 81, 83
Low-voltage DC (LVDC) bus microgrid system, 193–196
Low-voltage ride-through (LVRT), 144, 235, 245, 249–250, See also Fault ride-through (FRT) capability
M
Magnetic circuit breakers, 83–84
Magnetizing current, 56
Maximum power point tracking (MPPT) system, 121–123, 194, 245, 247
Mechanical loss, 124, 128, 130
Medium-scale wind turbines, 23
Medium-voltage circuit breakers, 85
Metal-oxide-semiconductor field-effect transistors (MOSFETs), 96, 253
Microgrid system for flywheel energy storage, 193–196
Middle East, 9
Miniature circuit breakers, 81, 83
MOD-2 model, 29
Modified sine wave inverter, 97
Molded case circuit breaker (MCCB), 86
Morocco, 9
Motors, See specific types
Murray loop, 72
Mutual induction, 53
N
National Renewable Energy Laboratory (NREL), 1
Neodymium, 45
New Zealand, 8
Nickel-cadmium batteries, 160
Nickel-metal-hydride batteries, 160
North Africa, 9
O
Offshore wind energy, 6, 18, 24–25
Onshore wind farms, 24
Optimal power flow, 65
Oscillatory transients, 89
Output power efficiency calculation, 123–135, See also Wind generators, total efficiency calculation
Output power leveling by pitch angle control, 203–207, See also Pitch control
P
Park’s equations, 52
Permanent magnet synchronous generators, 45–46, 117, 250
advantages and disadvantages, 45–46
control block diagram, 247f
fault ride-through capability, 245–251
back-to-back converter control, 247–248
energy storage system control, 248–249
energy storage system design example, 250–251
energy storage system rating, 249–250
Persistent faults, 69
Per-unit and percent admittance, 68
Phase unbalance, 90
average wind speed-based method, 205
doubly fed induction generator systems, 237
doubly fed induction generator with supercapacitor system for constant power control, 199, 202–203
fault ride-through capability for wound field synchronous generator, 243
output power leveling, 203–207
stabilization methods comparison, 223–231
stabilization solutions, 213, 215–216
wind farm supervisory control, 203
Pole slips, 77
Polyswitch (polyfuse), 87
Portugal, 149
Power and energy ratings, superconducting magnetic energy storage systems, 178–189
Power coefficient, 28
active power-frequency control, 87–88
blade pitch angle control, See Pitch
control converters and devices, See Power electronics; specific types
flywheel energy storage system, 196–198
generalized predictive control, 204–205
grid code requirements, 143
maximum power point tracking system, 121–123
reactive, See Reactive power control
reactive power-voltage control, 88
supercapacitor energy storage system, 198–202
Power electronics, 95, See also specific types
AC-to-DC-to-AC converter, 240, 245
cost issues, 120
current source inverter, 107–110
cycloconverters, 104
DC-to-DC choppers, 100–103, See also DC-to-DC converter
doubly fed induction generator systems, 236
flywheel energy storage system, 197–198
inverters, 96–100, See also Inverters
permanent magnet synchronous generator, 245–248
pulse width modulation (PWM), 104–107
PWM voltage source converter, 107
rectifiers, 96
variable speed wind generators, 114–115
Power factor design criteria, 145
Power field-effect transistors (FETs), 102
Power generation, conventional, 60–61
Power in the wind, 26
Power output
from practical turbines, 28–29
Power produced by wind generator blades, 119
Power quality, 89–91, See also Frequency stability; Voltage stability
energy storage devices for improving, 155–168, See also Energy storage systems
comparing systems, 168
flywheel system, 189–198, See also Flywheel energy storage system
SMES, 168–189, See also Superconducting magnetic energy storage
supercapacitor system for constant power control, 198–203, See also Supercapacitor energy storage systems
fault ride-through, See Fault ride-through (FRT) capability
fault ride-through, See Fault ridethrough (FRT) capability
grid code requirements, 144
output power leveling using pitch angle control, 203–207, See also Pitch control
phase unbalance, 90
transient stability enhancement, See Transient stability enhancement solutions
wind speed variations and, 142, 155
Power storage systems, See Energy storage systems
Power system analysis, 64–65, 91, See also Electrical power systems
fault analysis, 70–71, See also Faults
frequency fluctuation calculation, 173, See also Frequency stability
per-unit system and base quantities, 66–68
power flow study, 65
Power System Computer Aided Design/Electromagnetic Transients in DC (PSCAD/EMTDC), 123, 132, 169
Power system design and operation, grid integration issues, 149–150
classification, 73
frequency, 76–77, See also Frequency stability
voltage, 77–80, See also Voltage stability
Power system stabilizer (PSS), 44
Probability density function (pdf), 123, 134–135
Proportional-integral (PI) controllers, 171–172, 216, 217, 237, 239, 242
Pulse width modulation (PWM), 104–107
current source inverters, 109–110
duty cycle, 105
harmonics, 107
rotor-side converter control, 238
SMES model, 170
voltage source converter, 107, 117, 217–219, 240
Q
R
Radio interference, 62
Random wind speed variations, power quality fluctuations due to, 142
Rated speed, 30
Reactive power control, 87
doubly fed induction generator fault ride-through capability and, 237–240
grid code requirements, 144, 145
power factor design criteria, 145
power-voltage control, 88
Reluctance, 51–52, See also Synchronous reluctance machines
Residual-current devices (RCDs), 84, 86
Resonance conditions, 148
Resonant transformers, 57
Rotating-armature type synchronous generators, 39–40
Rotating-field type synchronous generators, 39–40
Rotating speed-based power control, 121–122
Rotating transformer, 47
Rotor angle stability, 73–76, 77
Rotor blades, 20
Rotors, 38
multimass shaft system, 46
S
Salient-pole Synchronous generators, 40–41
Samarium-cobalt, 45
Self-excitation, 79
Short-circuit current, 82
Short-circuit fault analysis, 65, 68–72, See also Faults
Short-circuit fault protection, See Circuit breakers; Fault protection
Short-term voltage stability, 80
Silicon-controlled rectifiers (SCRs), 104
current source inverters, 108–109
Sinusoidal pulse width modulation, 105–106
Six-pole induction generators or motors, 48, 115, See also Induction generators; Wind generators
Slack bus, 65
induction machine efficiency calculation issues, 123, 127–130
Slip ring rotor, 49
Slip rings, 114
Slip-torque curve, 128f Small-disturbance rotor angle stability, 74–75
Small-disturbance voltage stability, 79
Small-scale wind turbines, 23
SMES, See Superconducting magnetic energy storage
Solar thermal power plants, 167
Solid-core rotor, 49
South Korea, 8
Space vector modulation (SVM), 105
Speed controller, fault ride-through for wound field synchronous generator, 242–243
Squirrel-cage induction generators, 113, 189, 194
Stability, frequency, See Frequency stability
Stability, voltage, See Voltage stability
Stabilization methods, 213–231, See also Transient stability enhancement solutions
braking resistor, 213, 220–221
control structure, 228
pitch control, 213, 215–216, See also Pitch control
unsuccessful reclosure fault model, 222–227
Stall (or passive) control, 31, 117
Static synchronous compensator (STATCOM), 213, 218–219
stabilization solutions comparison, 223–231
Static var compensators (SVCs), 89
Stators, 38
Steam-turbine generators, 40
Storage systems, See Energy storage systems
Stray-field transformers, 57
Stray load loss, 124, 127, 128, 135
Submarine cables, 72
Subtransmission circuits, 63–64
Sulfur hexafluoride (SF6) circuit breakers, 82, 85, 86
Supercapacitor energy storage systems, 150, 162–163, 198–203
capacitance, 199
configuration and control, 201–202
grid-side converter control, 200–201
hybrid systems, 168
individual turbine control, 199
rotor-side converter control, 199–200
wind farm supervisory control, 198, 203
Superconducting fault current limiters (SFCLs), 213–214, 221
stabilization methods comparison, 223–231
Superconducting magnetic bearings, 164
Superconducting magnetic energy storage (SMES), 156–159, 168–189, 213, 216–217
hybrid storage systems, 168
low-pass filter time constant selection, 178, 182–188, 208
low-temperature and high-temperature superconductor devices, 158
potential utility applications, 158
power and energy ratings, 178–189
power electronics, 157–158, 168, 217–218
power system frequency calculation, 173
quenching, 214
required energy storage capacity estimation, 184, 186, 208
simulation results, 174–178, 207–208
stabilization methods comparison, 223–231
stabilization solutions, 213–214, 216–218
stored energy and rated power specifications, 157
wind power fluctuation effects on smoothing, 184, 186
Superconductor devices, 158, See also Superconducting magnetic energy storage
Superheterodyne receiver, 57
Supervisory control and data acquisition (SCADA) capability, 145
Supplemental circuit protectors, 83
Switched reluctance generator system, fault ride-through capability, 251–254
Synchronous condensers, 89
Synchronous generators, 37, 39–46, 240
automatic voltage regulator system, 43
circuit equation, 41
electrical power systems, 59
fault ride-through capability, permanent magnet system, 245–251
back-to-back converter control, 247–248
energy storage system control, 248–249
energy storage system design example, 250–251
energy storage system rating, 249–250
fault ride-through capability, wound field system, 240–245
excitation controller, 244
grid-side converter control, 244–245
pitch controller, 244
governor control system, 43
multimass shaft system, 46
parameters (table), 43
permanent magnet systems, See Permanent magnet synchronous generators
power generation industry use, 115
power system stability, 44, 72–73, See also Stabilization methods
rotating-armature and rotating-field types, 39–40
self-excitation, 79
transient stability analysis model system, 214–215
wind generators, 113, 117, See also Wind generators
Synchronous homopolar machines, 191
Synchronous motors, 39, See also Synchronous generators
circuit equation, 44
induction motor difference, 47–48
synchronous speed, 48
Synchronous reluctance machines (SRMs), 51–52
fault ride-through capability for switched system, 251–254
flywheel systems and, 191
Synchronous speed, 48
Synchroscope, 43
T
Taiwan, 8
Tesla coil, 57
Thermal magnetic circuit breakers, 84
Thermoelectric energy storage (TEES), 167
Three-phase AC power systems, 59
Three-phase transformer, 57
“Thumper” test, 72
Time-domain reflectometer, 72
Tip speed ratio, 28
Total efficiency calculation for wind generators, See Wind generators, total efficiency calculation
Tower, 20
applications, 59
practical operation, 56
rotating (induction motor), 47
turn ratio, 55
Transient faults, 69
grid integration issues, 141–142
Transients, 89–90, See also Power quality; Transient faults; Voltage dips; Voltage stability
Transient stability enhancement solutions, 213–231
braking resistor, 213, 220–221
comparisons of methods, 221–231
control structure analysis, 228
unsuccessful reclosure fault model, 222–227
pitch angle control, 213, 215–216, See also Pitch control
synchronous generator power system model, 214–215
Transient stability issues, 75, 213
Transient stability limit, 75
Transient state, wind generator total efficiency calculation, 123, 132–133, 208
Transmission lines, 61–63, See also Electric power transmission
TRIACs, 104
Triplen harmonics, 91
Tunisia, 9
Turbine-generator multimass shaft system, 46
Turn ratio, 55
U
Ultracapacitors, 162–163, See also Supercapacitor energy storage systems
Underground power cables, 69
Uninterruptible power supply (UPS), 163, 169, 195, 213
United States wind energy market, 6
Upwind horizontal axis wind turbine, 22
V
Vacuum circuit breakers, 82, 85
Vacuum resin infusion, 20
Valve-regulated lead acid (VRLA) batteries, 160
Van de Graaff generator, 57
Variability of wind power, See Wind power variability
Variable capacitor, 39
Variable speed wind energy conversion systems, 18, 114–115
fault ride-through capability, 235–254, See also Fault ride-through (FRT) capability
maximum power point tracking system, 121–123
Variac, 57
Varley loop, 72
Vertical axis wind turbine (VAWT), 20–22
Voltage collapse, 77
Voltage control, 87, See also Voltage source converter
automatic voltage regulator system, 43, 143, 169, 215
DC-to-DC chopper, 100–103, See also DC-to-DC converter
dynamic voltage restorer, 162
excitation controller for synchronous generator fault ride-through capability, 244
flywheel system, 196
grid code requirements, 143, 145–146
islanded network, 148
permanent magnet synchronous generator, 246–250
power generation industry generators, 115
PWM voltage source converter, 107, 217–219
reactive power-voltage control, 88
SMES applications, 158, 169–172, See also Superconducting magnetic energy storage
STATCOM (static synchronous compensator), 213, 218–219
transient stability analysis model system, 215
Voltage dips, 66–67, 90, 146, 195, 235–236, 246, See also Voltage sags;
Voltage stability Voltage operating range requirements, 143
Voltage sags, 89, 144, 162–163, 246–250, See also Voltage dips; Voltage stability
Voltage source converter (VSC), 78, 95, 107–108, 110, 117, 157, 170–171, 217, 219
comparing stabilization solutions, 228
DC bus microgrid system, 193
STATCOM (static synchronous compensator), 213, 218–219
Voltage source inverter (VSI), 117, 240
STATCOM (static synchronous compensator), 218–219
Voltage stability, 77–80, 247f, See also Voltage dips; Voltage sags
fault ride-through, See Fault ride-through (FRT) capability
grid integration issues, 141–142
large- and small-disturbance, 79
long- and short-duration variations, 89–90
low-voltage ride-through, 144, 235, 245, 249–250
power quality issues, 89–90, See also Power quality
rotor angle instability, 77
self-excitation-related overvoltages, 79
short- and long-term, 80
wind speed variations and, 142, 155
Voltage transformers (VTs), 58
Volt-ampere, 66
W
Waveform distortion, 90
Weibull function, 134
Wind, 2
advantages and disadvantages, 2–3
capacity credit, 151
intermittent, 141
research organizations, 1
Wind energy conversion systems, 17, 113, See also Wind generators; Wind turbines
fundamental concept, 17
generator comparisons (table), 118
induction generators, 117–118, See also Induction generators
synchronous generators, 117, See also Synchronous generators
Wind farm communications and external control, 144
Wind farm modeling, 144
Wind farm supervisory controller (WFSC), 198, 203
flow chart for implementation, 204f
Wind generators, 37, 113, 115, See also Wind energy conversion systems; specific issues, types
comparison of types (table), 118
grid integration, See Grid integration issues
induction generators, See Induction generators
losses, 124
maximum power point tracking system, 121–123
optimal speed of rotation, 120
power characteristics, 118–121
power curves, 119
power electronics interface, 95–96, 110, See also Power electronics
synchronous generators, See Synchronous generators
torque curves, 120
transient faults and, 141, See also Fault ride-through (FRT) capability
Wind generators, total efficiency calculation, 123–135
calculation method outline, 123–125
copper loss and iron loss, 126
generator input power calculation, 125
probability density function, 123, 134–135
simulation results, 130–131, 136
windage loss and stray load loss, 127
wind turbine power equations, 125
Wind power variability, 142
forecasting, 142
power quality fluctuations due to random wind speed variations, 142
Wind speed-based efficiency calculation, 134–135
Wind speed-based power control, 122
Wind speed variation
effect on SMES smoothing, 184, 186
energy storage system rating, 250
power quality fluctuations due to, 142, 155
variable speed turbine operation, 18
Wind turbine blade pitch control, See Pitch control
Wind turbine controller system, 20, 198–203, 203
Wind turbine locations, 3, 18, 24
Wind turbine modeling
design speed, 30
doubly fed induction generator systems, 237
ideal turbine power output, 25–28
MOD-2, 29
pitch mechanism, 30
practical turbine power output, 28–29
Wind turbines, 18, 37, See also Wind generators
design speed, 30
power equation, 125
Worldwide status of wind energy, 3–9
Africa and Middle East, 9
annual market forecast, 12f
global installed capacity, 10f
Pacific, 8
Wound field synchronous generator, fault ride-through capability, 240–245
Y
Yawing, 18
Z
Zero-point quenching, 81