風(fēng)電場(chǎng)外文翻譯

1、<p><b>　　外文翻譯</b></p><p><b>　　原文</b></p><p>　　Wind Farm (IG)</p><p>　　This demonstration illustrates phasor simulation of a 9-MW wind farm using Inducti

2、on Generators (IG) driven by variable-pitch wind turbines</p><p>　　Richard Gagnon (Hydro-Quebec)</p><p><b>　　Contents</b></p><p>　　· Model Description</p>&l

3、t;p>　　· Demonstration</p><p>　　· How To Regenerate Initial Conditions</p><p>　　Model Description</p><p>　　A wind farm consisting of six 1.5-MW wind turbines is connecte

4、d to a 25-kV distribution system exports power to a 120-kV grid through a 25-km 25-kV feeder. The 9-MW wind farm is simulated by three pairs of 1.5 MW wind-turbines. Wind turbines use squirrel-cage induction generators (

5、IG). The stator winding is connected directly to the 60 Hz grid and the rotor is driven by a variable-pitch wind turbine. The pitch angle is controlled in order to limit the generator output power at its nominal value &l

6、t;/p><p>　　Reactive power absorbed by the IGs is partly compensated by capacitor banks connected at each wind turbine low voltage bus (400 kvar for each pair of 1.5 MW turbine). The rest of reactive power requi

7、red to maintain the 25-kV voltage at bus B25 close to 1 pu is provided by a 3-Mvar STATCOM with a 3% droop setting.</p><p>　　Open the "Wind Farm" block and look at "Wind Turbine 1". Open

8、the turbine menu and look at the two sets of parameters specified for the turbine and the generator. Each wind turbine block represents two 1.5 MW turbines. Open the turbine menu, select "Turbine data" and chec

9、k "Display wind-turbine power characteristics". The turbine mechanical power as function of turbine speed is displayed for wind speeds ranging from 4 m/s to 10 m/s. The nominal wind speed yielding the nominal m

10、echanical power (1</p><p>　　The wind speed applied to each turbine is controlled by the "Wind 1" to "Wind 3" blocks . Initially, wind speed is set at 8 m/s, then starting at t=2s for &quo

11、t;Wind turbine 1", wind speed is rammed to 11 m/s in 3 seconds. The same gust of wind is applied to Turbine 2 and Turbine 3, respectively with 2 seconds and 4 seconds delays. Then, at t=15 s a temporary fault is app

12、lied at the low voltage terminals (575 V) of "Wind Turbine 2".</p><p>　　Demonstration</p><p>　　Turbine response to a change in wind speed</p><p>　　Start simulation and obs

13、erve the signals on the "Wind Turbines" scope monitoring active and reactive power, generator speed, wind speed and pitch angle for each turbine. For each pair of turbine the generated active power starts incre

14、asing smoothly (together with the wind speed) to reach its rated value of 3 MW in approximately 8s. Over that time frame the turbine speed will have increased from 1.0028 pu to 1.0047 pu. Initially, the pitch angle of th

15、e turbine blades is zero degree. When the outp</p><p>　　Operation of protection system</p><p>　　At t=15 s, a phase to phase fault is applied at wind turbine 2 terminals, causing the turbine to t

16、rip at t=15.11 s. If you look inside the "Wind Turbine Protections" block you will see that the trip has been initiated by the AC Undervoltage protection. After turbine 2 has tripped, turbines 1 and 3 continue

17、to generate 3 MW each.</p><p>　　Impact of STATCOM</p><p>　　You will now observe the impact of the "STATCOM". First, open the "Three-Phase Fault" block menu and disable the ph

18、ase to phase fault. Then put the "STATCOM" out of service by double clicking the "Manual Switch" block connected to the "Trip" input of the "STATCOM". Restart simulation. Observe o

19、n " B25 Bus" scope that because of the lack of reactive power support, the voltage at bus "B25" now drops to 0.91pu. This low voltage condition results in an overload of the IG of "Wind Turbine 1

20、". "Wind T</p><p>　　How To Regenerate Initial Conditions</p><p>　　This demo is set-up with all states initialized so that the simulation starts in steady-state. The initial conditions

21、have been saved in the "power_wind_ig_xinit.mat" file. When you open this model, the InitFcn callback (in the Model Properties/Callbacks) automatically loads into your workspace the contents of this .mat file (

22、"xInitial" variable).</p><p>　　If you modify this model, or change parameter values of power components, the initial conditions stored in the "xInitial" variable will no longer be valid a

23、nd Simulink® will issue an error message. To regenerate the initial conditions for your modified model, follow the steps listed below:</p><p>　　1. In the Simulation/Configuration Parameters/Data Import/

24、Export Parameters menu, uncheck the "Initial state" parameter.</p><p>　　2. Open the "Wind Farm" subsystem and in the Timer blocks labeled "Wind1" and "Wind2", Wind3&qu

25、ot; temporarily disable the changes of wind speed by multiplying the "Time(s)" vector by 100.</p><p>　　3. In the "Wind Farm" subsystem, double click on the "Three-Phase Fault" b

26、lock and disable the AB to ground fault (deselect "Phase A Fault" and "Phase B Fault").</p><p>　　4. Start simulation. When Simulation is completed, verify that steady state has been reach

27、ed by looking at waveforms displayed on the scopes. The final states which have been saved in the "xFinal" array can be used as initial states for future simulations. Executing the next two commands copies thes

28、e final conditions in "xInitial" and saves this variable in a new file (myModel_init.mat).</p><p>　　5. >> xInitial=xFinal;</p><p>　　6. >> save myModel_init xInitial</p&g

29、t;<p>　　7. In the File/Model Properties/Callbacks/InitFcn window, change the name of the initialization file from "power_wind_ig_xinit" to "myModel_init". Next time you open this model, the var

30、iable xInitial saved in the myModel_init.mat file will be loaded in your workspace.</p><p>　　8. In the Simulation/Configuration Parameters menu, check "Initial state".</p><p>　　9. Star

31、t simulation and verify that your model starts in steady-state.</p><p>　　10. Open the "Wind Farm" subsystem and in the Timer blocks labeled "Wind1", "Wind2" and Wind3" re-e

32、nable the changes of wind speed respectively a t=2 s , t=4 s and t=6 s (remove the 100 multiplication factors).</p><p>　　11. In the "Wind Farm" subsystem, re-enable the AB to ground fault in the &q

33、uot;Three-Phase Fault" block (check "Phase A Fault" and "Phase B Fault")</p><p>　　12.Save your Model.</p><p>　　Wind Farm (DFIG Phasor Model)</p><p>　　This d

34、emonstration illustrates phasor simulation of a 9 MW wind farm using Doubly-Fed Induction Generator (DFIG) driven by a wind turbine</p><p>　　Richard Gagnon, Bernard Saulnier, Alain Forcione (Hydro-Quebec)<

35、;/p><p>　　Note: This demo uses a generic model of a DFIG wind turbine. The model is useful for education and academic works.</p><p><b>　　Contents</b></p><p>　　· Model

36、Description</p><p>　　· Demonstration</p><p>　　· How To Regenerate Initial Conditions</p><p>　　Model Description</p><p>　　A 9-MW wind farm consisting of six 1.

37、5 MW wind turbines connected to a 25-kV distribution system exports power to a 120-kV grid through a 30-km, 25-kV feeder. A 2300V, 2-MVA plant consisting of a motor load (1.68 MW induction motor at 0.93 PF) and of a 200-

38、kW resistive load is connected on the same feeder at bus B25. Both the wind turbine and the motor load have a protection system monitoring voltage, current and machine speed. The DC link voltage of the DFIG is also monit

39、ored.</p><p>　　Wind turbines use a doubly-fed induction generator (DFIG) consisting of a wound rotor induction generator and an AC/DC/AC IGBT-based PWM converter. The stator winding is connected directly to

40、the 60 Hz grid while the rotor is fed at variable frequency through the AC/DC/AC converter. The DFIG technology allows extracting maximum energy from the wind for low wind speeds by optimizing the turbine speed, while mi

41、nimizing mechanical stresses on the turbine during gusts of wind. The optimum turbine sp</p><p>　　The wind-turbine model is a phasor model that allows transient stability type studies with long simulation ti

42、mes. In this demo, the system is observed during 50 s.</p><p>　　Open the wind turbine block menu and look at the four sets of parameters specified for the turbine, the generator and the converters (grid-side

43、 and rotor-side). The 6-wind-turbine farm is simulated by a single wind-turbine block by multiplying the following three parameters by six, as follows:</p><p>　　1. The nominal wind turbine mechanical output:

44、 6*1.5e6 watts, specified in the Turbine data menu</p><p>　　2. The generator rated power: 6*1.5/0.9 MVA (6*1.5 MW at 0.9 PF), specified in the Generator data menu</p><p>　　3. The nominal DC bus

45、capacitor: 6*10000 microfarads, specified in the Converters data menu</p><p>　　Also, notice in the Control parameters menu that the "Mode of operation" is set to " Voltage regulation". Th

46、e terminal voltage will be controlled to a value imposed by the reference voltage (Vref = 1 pu) and the voltage droop (Xs = 0.02 pu).</p><p>　　Demonstration</p><p>　　1. Turbine response to a cha

47、nge in wind speed</p><p>　　Open the "Wind Speed" step block specifying the wind speed. Initially, wind speed is set at 8 m/s, then at t = 5s, wind speed increases suddenly at 14 m/s. Start simulati

48、on and observe the signals on the "Wind Turbine" scope monitoring the wind turbine voltage, current, generated active and reactive powers, DC bus voltage and turbine speed. At t = 5 s, the generated active powe

49、r starts increasing smoothly (together with the turbine speed) to reach its rated value of 9 MW in approximately 15 s. O</p><p>　　2. Simulation of a voltage sag on the 120-kV system</p><p>　　You

50、 will now observe the impact of a voltage sag resulting from a remote fault on the 120-kV system. First, in the wind speed step block, disable the wind speed step by changing the Final value from 14 to 8 m/s. Then open t

51、he 120-kV voltage source menu. In the parameter "Time variation of", select " Amplitude". A 0.15 pu voltage drop lasting 0.5 s is programmed to occur at t = 5 s. Make sure that the control mode is sti

52、ll in Var regulation with Qref = 0. Start simulation and open the "Grid" scop</p><p>　　Now, change the wind turbine control mode to "Voltage regulation" and repeat the test. You will noti

53、ce that the plant does not trip anymore. This is because the voltage support provided by the 5 Mvar reactive power generated by the wind-turbines during the voltage sag keeps the plant voltage above the 0.9 pu protection

54、 threshold. The plant voltage during the voltage sag is now 0.93 pu.</p><p>　　3. Simulation of a fault on the 25-kV system</p><p>　　Finally, you will now observe impact of a single phase-to-grou

55、nd fault occurring on the 25-kV line at B25 bus. First disable the 120-kV voltage step. Now open the "Fault" block menu and select "Phase A Fault". Check that the fault is programmed to apply a 9-cycl

56、e single-phase to ground fault at t = 5 s.</p><p>　　You should observe that when the wind turbine is in "Voltage regulation" mode, the positive-sequence voltage at wind-turbine terminals (V1_B575)

57、drops to 0.8 pu during the fault, which is above the undervoltage protection threshold (0.75 pu for a t > 0.1 s). The wind farm therefore stays in service. However, if the "Var regulation" mode is used with

58、Qref = 0, the voltage drops under 0.7 pu and the undervoltage protection trips the wind farm. We can now observe that the turbine speed increases. A</p><p>　　How To Regenerate Initial Conditions</p>&

59、lt;p>　　This demo is set-up with all states initialized so that the simulation starts in steady-state. The initial conditions have been saved in the "power_wind_dfig_xinit.mat" file. When you open this model,

60、 the InitFcn callback (in the Model Properties/Callbacks) automatically loads into your workspace the contents of this .mat file ("xInitial" variable).</p><p>　　If you modify this model, or change

61、parameter values of power components, the initial conditions stored in the "xInitial" variable will no longer be valid and Simulink® will issue an error message. To regenerate the initial conditions for yo

62、ur modified model, follow the steps listed below:</p><p>　　1. In the Simulation/Configuration Parameters/Data Import/Export Parameters menu, uncheck the "Initial state" parameter.</p><p&

63、gt;　　2. Double click on the Step block labeled "Wind Speed (m/s)" and temporarily disable the change of wind speed by multiplying the Step time by 100.</p><p>　　3. Double click on the Breaker block

64、 and make sure that no fault is applied (Phase A, B and C checkboxes not selected).</p><p>　　4. Double click on the 120 kV voltage source block and make sure that the "Time variation of" parameter

65、is set to "None".</p><p>　　5. Start simulation. When Simulation is completed, verify that steady state has been reached by looking at waveforms displayed on the scopes. The final states which have

66、been saved in the "xFinal" array can be used as initial states for future simulations. Executing the next two commands copies these final conditions in "xInitial" and saves this variable in a new file

67、 (myModel_init.mat).</p><p>　　6. >> xInitial=xFinal;</p><p>　　7. >> save myModel_init xInitial</p><p>　　8. In the File/Model Properties/Callbacks/InitFcn window, change

68、the name of the initialization file from "power_wind_dfig_xinit" to "myModel_init". Next time you open this model, the variable xInitial saved in the myModel_init.mat file will be loaded in your works

69、pace.</p><p>　　9. In the Simulation/Configuration Parameters menu, check "Initial state".</p><p>　　10. Start simulation and verify that your model starts in steady-state.</p>&l

70、t;p>　　11. Double click on the Step block labeled "Wind Speed (m/s)" and re-enable the change of wind speed at t=5 s (remove the 100 multiplication factor).</p><p>　　12. Save your Model.</p>

71、;<p>　　Wind Farm - DFIG Detailed Model</p><p>　　This demonstration illustrates simulation of a 9 MW wind farm using a detailed model of a Doubly-Fed Induction Generator (DFIG) driven by a wind turbine

72、</p><p>　　Richard Gagnon (Hydro-Quebec)</p><p><b>　　Contents</b></p><p>　　· 1. Simulation Methods of the DFIG</p><p>　　· 2. Circuit Description<

73、;/p><p>　　· 3. Demonstration</p><p>　　· 4. How To Regenerate Initial Conditions</p><p>　　1. Simulation Methods of the DFIG</p><p>　　Depending on the range of fre

74、quencies to be represented, three simulation methods are currently available in SimPowerSystems? to model VSC based energy conversion systems connected on power grids.</p><p>　　The detailed model (discrete)

75、such as the one presented in this demo. The detailed model includes detailed representation of power electronic IGBT converters. In order to achieve an acceptable accuracy with the 1620 Hz and 2700 Hz switching frequenci

76、es used in this demo, the model must be discretized at a relatively small time step (5 microseconds). This model is well suited for observing harmonics and control system dynamic performance over relatively short periods

77、 of times (typically hundreds </p><p>　　The average model (discrete) such as the one presented in the “power_wind_dfig_avg.mdl” model in the DR demo library. In this type of model the IGBT Voltage-sourced co

78、nverters (VSC) are represented by equivalent voltage sources generating the AC voltage averaged over one cycle of the switching frequency. This model does not represent harmonics, but the dynamics resulting from control

79、system and power system interaction is preserved. This model allows using much larger time steps (typically 50 mi</p><p>　　The phasor model (continuous) such as the one presented in the “power_wind_dfig” mod

80、el in the DR demo library. This model is better adapted to simulate the low frequency electromechanical oscillations over long periods of time (tens of seconds to minutes). In the phasor simulation method, the sinusoidal

81、 voltages and currents are replaced by phasor quantities (complex numbers) at the system nominal frequency (50 Hz or 60 Hz).This is the same technique which is used in transient stability software</p><p>　　2

82、. Circuit Description</p><p>　　A 9 MW wind farm consisting of six 1.5 MW wind turbines connected to a 25 kV distribution system exports power to a 120 kV grid through a 30 km, 25 kV feeder.</p><p&

83、gt;　　Wind turbines using a doubly-fed induction generator (DFIG) consist of a wound rotor induction generator and an AC/DC/AC IGBT-based PWM converter. The stator winding is connected directly to the 60 Hz grid while the

84、 rotor is fed at variable frequency through the AC/DC/AC converter. The DFIG technology allows extracting maximum energy from the wind for low wind speeds by optimizing the turbine speed, while minimizing mechanical stre

85、sses on the turbine during gusts of wind.</p><p>　　In this demo the wind speed is maintained constant at 15 m/s. The control system uses a torque controller in order to maintain the speed at 1.2 pu. The reac

86、tive power produced by the wind turbine is regulated at 0 Mvar.</p><p>　　Right-click on the “DFIG Wind Turbine” block and select “Look Under Mask” to see how the model is built. The sample time used to discr

87、etize the model (Ts= 50 microseconds)is specified in the Initialization function of the Model Properties.</p><p>　　Open the “DFIG Wind Turbine” block menu to see the data of the generator, the converter, the

88、 turbine, the drive train and the control systems. In the Display menu select “Turbine data for 1 wind turbine”, check "Display wind turbine power characteristics" and then click Apply. The turbine Cp curves ar

89、e displayed in Figure 1. The turbine power, the tip speed ratio lambda and the Cp values are displayed in Figure 2 as function of wind speed. For a wind speed of 15 m/s, the turbine output power is </p><p>　

90、　3. Demonstration</p><p>　　In this demo you will observe the steady-state operation of the DFIG and its dynamic response to voltage sag resulting from a remote fault on the 120-kV system. Open the “120 kV” b

91、lock modeling the voltage source and see how a six-cycle 0.5 pu voltage drop is programmed at t=0.03 s</p><p>　　Start simulation. Observe voltage and current waveforms on the Scope. At simulation start the “

92、xInitial” variable containing the initial state variables is automatically loaded (from the “power_wind_dfig_avg_xinit.mat” file specified in the Model Properties) so that the simulation starts in steady state.</p>

93、<p>　　Initially the DFIG wind farm produces 9 MW. The corresponding turbine speed is 1.2 pu of generator synchronous speed. The DC voltage is regulated at 1150 V and reactive power is kept at 0 Mvar. At t=0.03 s t

94、he positive-sequence voltage suddenly drops to 0.5 p.u. causing an oscillation on the DC bus voltage and on the DFIG output power. During the voltage sag the control system tries to regulate DC voltage and reactive power

95、 at their set points (1150 V, 0 Mvar). The system recovers in approximate</p><p>　　4. How To Regenerate Initial Conditions</p><p>　　This demo is set-up with all states initialized so that the si

96、mulation starts in steady-state. Otherwise, due to the long time constants of the electromechanical part of the wind turbine model and to its relatively slow regulators you would have to wait for tens of seconds before r

97、eaching steady-state. The initial conditions have been saved in the "power_wind_dfig_det.mat" file. When you start simulation, the InitFcn callback (in the Model Properties/Callbacks) automatically loads into y

98、our work</p><p>　　If you modify this model, or change parameter values of power components, the initial conditions stored in the "xInitial" variable will no longer be valid and Simulink® will

99、issue an error message. To regenerate the initial conditions for your modified model, follow the steps listed below:</p><p>　　1. In the Simulation/Configuration Parameters menu, uncheck the "Initial sta

100、te" parameter.</p><p>　　2. In the 120 kV Three-phase Voltage Source menu, disable the source voltage step by setting the "Time variation of " parameter to "none".</p><p>

101、;　　3. In order to shorten the time required to reach steady-state, you will have to temporarily decrease the inertia of the turbine-generator group. Open the DFIG Wind Turbine menu and in the Drive train data and Generat

102、or data, divide the H inertia constants by 10.</p><p>　　4. Change the Simulation Stop Time to 5 seconds. Note that in order to generate initial conditions coherent with the 60 Hz voltage source phase angles,

103、 the Stop Time must be an integer number of 60 Hz cycles.</p><p>　　5. Change the Simulation Mode from "Normal" to "Accelerator".</p><p>　　6. Start simulation. When Simulation

104、 is completed, verify that steady state has been reached by looking at waveforms displayed on the Scope. The final states which have been saved in the "xFinal" structure with time can be used as initial states