IEEE Power & Energy Magazine - May/June 2014 - 90

Dynamic Voltage Regulation Modes

Active Power Curtailment

80

Ramp Rates Between
Set Point Changes
Are Controlled

75
70

80

Power (MW)

Set Point (MW)

through the ScAdA hMi, the plant control system can be
set to operate in one of the three modes of automatic voltage
regulation (AvR): voltage regulation, power-factor regulaCurrent SP New SP
tion, or reactive-power control. the three AvR modes are
Active Power Limit 290.00 290.00 MW
illustrated in the ScAdA hMi screen shown in Figure 2.
Ramp Up Rate
15.0
15.0 MW/min
note that the plant can operate in only one of the three operRamp Down Rate
15.0
15.0 MW/min
ating modes at any time.
in the voltage-regulation mode, the controller maintains
the specified voltage set point at the poi by regulating the
Cancel
Confirm
reactive power produced by the inverters as well as other
Changes
Changes
devices such as capacitor banks. in the power-factor regulation mode, the controller maintains the specified power facfigure 4. An active power curtailment HMI.
tor. the operation of the controller is illustrated in Figure 3,
which shows field data from a pv plant producing about
212 MW of active power at that time.
Figure 3 illustrates the response of the plant when the
output limit. it also uses the active power management function to ensure that the plant output does not exceed the desired power factor set point is changed from 0.98 to 1.0. the
ramp rates, to the extent possible. it cannot, however, always controller commands the inverters to change their reactive
accommodate rapid reduction in irradiance due to cloud cover. power output to meet the new power factor set point, using
a closed-loop control mechanism. the figure illustrates that
the inverters respond very rapPower Curtailment at Different Levels
idly. Within a few seconds (<4 s)
100
100
the new set point is achieved in a
95
95
closed-loop control mode. More
specifically, the rise time to reach
Inverters Are Turned Down/Off
90
90
90% of steady-state value shown
to Curtail Output
in the figure is about 3.2 s.
85
85

Active Power
Management

75

through the ScAdA hMi, the
controller can also be set to control the active power output of the
plant. When the control system
detects that the active power at poi
exceeds the specified set point, it

70
0

2

4

6

8

10
12
Time (min)

14

16

18

20

figure 5. Power curtailment at different levels.

Output of Each Block

Plant Output Power
Additional Energy Captured

Power

Power

Increase in
Power Limit

Curtailed

Block

Potential
Power

Plant
Output Limit

Time

figure 6. The impact of cloud passage under curtailment.
90

ieee power & energy magazine

may/june 2014



Table of Contents for the Digital Edition of IEEE Power & Energy Magazine - May/June 2014

IEEE Power & Energy Magazine - May/June 2014 - Cover1
IEEE Power & Energy Magazine - May/June 2014 - Cover2
IEEE Power & Energy Magazine - May/June 2014 - 1
IEEE Power & Energy Magazine - May/June 2014 - 2
IEEE Power & Energy Magazine - May/June 2014 - 3
IEEE Power & Energy Magazine - May/June 2014 - 4
IEEE Power & Energy Magazine - May/June 2014 - 5
IEEE Power & Energy Magazine - May/June 2014 - 6
IEEE Power & Energy Magazine - May/June 2014 - 7
IEEE Power & Energy Magazine - May/June 2014 - 8
IEEE Power & Energy Magazine - May/June 2014 - 9
IEEE Power & Energy Magazine - May/June 2014 - 10
IEEE Power & Energy Magazine - May/June 2014 - 11
IEEE Power & Energy Magazine - May/June 2014 - 12
IEEE Power & Energy Magazine - May/June 2014 - 13
IEEE Power & Energy Magazine - May/June 2014 - 14
IEEE Power & Energy Magazine - May/June 2014 - 15
IEEE Power & Energy Magazine - May/June 2014 - 16
IEEE Power & Energy Magazine - May/June 2014 - 17
IEEE Power & Energy Magazine - May/June 2014 - 18
IEEE Power & Energy Magazine - May/June 2014 - 19
IEEE Power & Energy Magazine - May/June 2014 - 20
IEEE Power & Energy Magazine - May/June 2014 - 21
IEEE Power & Energy Magazine - May/June 2014 - 22
IEEE Power & Energy Magazine - May/June 2014 - 23
IEEE Power & Energy Magazine - May/June 2014 - 24
IEEE Power & Energy Magazine - May/June 2014 - 25
IEEE Power & Energy Magazine - May/June 2014 - 26
IEEE Power & Energy Magazine - May/June 2014 - 27
IEEE Power & Energy Magazine - May/June 2014 - 28
IEEE Power & Energy Magazine - May/June 2014 - 29
IEEE Power & Energy Magazine - May/June 2014 - 30
IEEE Power & Energy Magazine - May/June 2014 - 31
IEEE Power & Energy Magazine - May/June 2014 - 32
IEEE Power & Energy Magazine - May/June 2014 - 33
IEEE Power & Energy Magazine - May/June 2014 - 34
IEEE Power & Energy Magazine - May/June 2014 - 35
IEEE Power & Energy Magazine - May/June 2014 - 36
IEEE Power & Energy Magazine - May/June 2014 - 37
IEEE Power & Energy Magazine - May/June 2014 - 38
IEEE Power & Energy Magazine - May/June 2014 - 39
IEEE Power & Energy Magazine - May/June 2014 - 40
IEEE Power & Energy Magazine - May/June 2014 - 41
IEEE Power & Energy Magazine - May/June 2014 - 42
IEEE Power & Energy Magazine - May/June 2014 - 43
IEEE Power & Energy Magazine - May/June 2014 - 44
IEEE Power & Energy Magazine - May/June 2014 - 45
IEEE Power & Energy Magazine - May/June 2014 - 46
IEEE Power & Energy Magazine - May/June 2014 - 47
IEEE Power & Energy Magazine - May/June 2014 - 48
IEEE Power & Energy Magazine - May/June 2014 - 49
IEEE Power & Energy Magazine - May/June 2014 - 50
IEEE Power & Energy Magazine - May/June 2014 - 51
IEEE Power & Energy Magazine - May/June 2014 - 52
IEEE Power & Energy Magazine - May/June 2014 - 53
IEEE Power & Energy Magazine - May/June 2014 - 54
IEEE Power & Energy Magazine - May/June 2014 - 55
IEEE Power & Energy Magazine - May/June 2014 - 56
IEEE Power & Energy Magazine - May/June 2014 - 57
IEEE Power & Energy Magazine - May/June 2014 - 58
IEEE Power & Energy Magazine - May/June 2014 - 59
IEEE Power & Energy Magazine - May/June 2014 - 60
IEEE Power & Energy Magazine - May/June 2014 - 61
IEEE Power & Energy Magazine - May/June 2014 - 62
IEEE Power & Energy Magazine - May/June 2014 - 63
IEEE Power & Energy Magazine - May/June 2014 - 64
IEEE Power & Energy Magazine - May/June 2014 - 65
IEEE Power & Energy Magazine - May/June 2014 - 66
IEEE Power & Energy Magazine - May/June 2014 - 67
IEEE Power & Energy Magazine - May/June 2014 - 68
IEEE Power & Energy Magazine - May/June 2014 - 69
IEEE Power & Energy Magazine - May/June 2014 - 70
IEEE Power & Energy Magazine - May/June 2014 - 71
IEEE Power & Energy Magazine - May/June 2014 - 72
IEEE Power & Energy Magazine - May/June 2014 - 73
IEEE Power & Energy Magazine - May/June 2014 - 74
IEEE Power & Energy Magazine - May/June 2014 - 75
IEEE Power & Energy Magazine - May/June 2014 - 76
IEEE Power & Energy Magazine - May/June 2014 - 77
IEEE Power & Energy Magazine - May/June 2014 - 78
IEEE Power & Energy Magazine - May/June 2014 - 79
IEEE Power & Energy Magazine - May/June 2014 - 80
IEEE Power & Energy Magazine - May/June 2014 - 81
IEEE Power & Energy Magazine - May/June 2014 - 82
IEEE Power & Energy Magazine - May/June 2014 - 83
IEEE Power & Energy Magazine - May/June 2014 - 84
IEEE Power & Energy Magazine - May/June 2014 - 85
IEEE Power & Energy Magazine - May/June 2014 - 86
IEEE Power & Energy Magazine - May/June 2014 - 87
IEEE Power & Energy Magazine - May/June 2014 - 88
IEEE Power & Energy Magazine - May/June 2014 - 89
IEEE Power & Energy Magazine - May/June 2014 - 90
IEEE Power & Energy Magazine - May/June 2014 - 91
IEEE Power & Energy Magazine - May/June 2014 - 92
IEEE Power & Energy Magazine - May/June 2014 - 93
IEEE Power & Energy Magazine - May/June 2014 - 94
IEEE Power & Energy Magazine - May/June 2014 - 95
IEEE Power & Energy Magazine - May/June 2014 - 96
IEEE Power & Energy Magazine - May/June 2014 - 97
IEEE Power & Energy Magazine - May/June 2014 - 98
IEEE Power & Energy Magazine - May/June 2014 - 99
IEEE Power & Energy Magazine - May/June 2014 - 100
IEEE Power & Energy Magazine - May/June 2014 - 101
IEEE Power & Energy Magazine - May/June 2014 - 102
IEEE Power & Energy Magazine - May/June 2014 - 103
IEEE Power & Energy Magazine - May/June 2014 - 104
IEEE Power & Energy Magazine - May/June 2014 - 105
IEEE Power & Energy Magazine - May/June 2014 - 106
IEEE Power & Energy Magazine - May/June 2014 - 107
IEEE Power & Energy Magazine - May/June 2014 - 108
IEEE Power & Energy Magazine - May/June 2014 - 109
IEEE Power & Energy Magazine - May/June 2014 - 110
IEEE Power & Energy Magazine - May/June 2014 - 111
IEEE Power & Energy Magazine - May/June 2014 - 112
IEEE Power & Energy Magazine - May/June 2014 - 113
IEEE Power & Energy Magazine - May/June 2014 - 114
IEEE Power & Energy Magazine - May/June 2014 - 115
IEEE Power & Energy Magazine - May/June 2014 - 116
IEEE Power & Energy Magazine - May/June 2014 - 117
IEEE Power & Energy Magazine - May/June 2014 - 118
IEEE Power & Energy Magazine - May/June 2014 - 119
IEEE Power & Energy Magazine - May/June 2014 - 120
IEEE Power & Energy Magazine - May/June 2014 - 121
IEEE Power & Energy Magazine - May/June 2014 - 122
IEEE Power & Energy Magazine - May/June 2014 - 123
IEEE Power & Energy Magazine - May/June 2014 - 124
IEEE Power & Energy Magazine - May/June 2014 - 125
IEEE Power & Energy Magazine - May/June 2014 - 126
IEEE Power & Energy Magazine - May/June 2014 - 127
IEEE Power & Energy Magazine - May/June 2014 - 128
IEEE Power & Energy Magazine - May/June 2014 - Cover3
IEEE Power & Energy Magazine - May/June 2014 - Cover4
https://www.nxtbook.com/nxtbooks/pes/powerenergy_091020
https://www.nxtbook.com/nxtbooks/pes/powerenergy_070820
https://www.nxtbook.com/nxtbooks/pes/powerenergy_050620
https://www.nxtbook.com/nxtbooks/pes/powerenergy_030420
https://www.nxtbook.com/nxtbooks/pes/powerenergy_010220
https://www.nxtbook.com/nxtbooks/pes/powerenergy_111219
https://www.nxtbook.com/nxtbooks/pes/powerenergy_091019
https://www.nxtbook.com/nxtbooks/pes/powerenergy_070819
https://www.nxtbook.com/nxtbooks/pes/powerenergy_050619
https://www.nxtbook.com/nxtbooks/pes/powerenergy_030419
https://www.nxtbook.com/nxtbooks/pes/powerenergy_010219
https://www.nxtbook.com/nxtbooks/pes/powerenergy_111218
https://www.nxtbook.com/nxtbooks/pes/powerenergy_091018
https://www.nxtbook.com/nxtbooks/pes/powerenergy_070818
https://www.nxtbook.com/nxtbooks/pes/powerenergy_050618
https://www.nxtbook.com/nxtbooks/pes/powerenergy_030418
https://www.nxtbook.com/nxtbooks/pes/powerenergy_010218
https://www.nxtbook.com/nxtbooks/pes/powerenergy_111217
https://www.nxtbook.com/nxtbooks/pes/powerenergy_091017
https://www.nxtbook.com/nxtbooks/pes/powerenergy_070817
https://www.nxtbook.com/nxtbooks/pes/powerenergy_050617
https://www.nxtbook.com/nxtbooks/pes/powerenergy_030417
https://www.nxtbook.com/nxtbooks/pes/powerenergy_010217
https://www.nxtbook.com/nxtbooks/pes/powerenergy_111216
https://www.nxtbook.com/nxtbooks/pes/powerenergy_091016
https://www.nxtbook.com/nxtbooks/pes/powerenergy_070816
https://www.nxtbook.com/nxtbooks/pes/powerenergy_050616
https://www.nxtbook.com/nxtbooks/pes/powerenergy_030416
https://www.nxtbook.com/nxtbooks/pes/powerenergy_010216
https://www.nxtbook.com/nxtbooks/ieee/powerenergy_010216
https://www.nxtbook.com/nxtbooks/pes/powerenergy_111215
https://www.nxtbook.com/nxtbooks/pes/powerenergy_091015
https://www.nxtbook.com/nxtbooks/pes/powerenergy_070815
https://www.nxtbook.com/nxtbooks/pes/powerenergy_050615
https://www.nxtbook.com/nxtbooks/pes/powerenergy_030415
https://www.nxtbook.com/nxtbooks/pes/powerenergy_010215
https://www.nxtbook.com/nxtbooks/pes/powerenergy_111214
https://www.nxtbook.com/nxtbooks/pes/powerenergy_091014
https://www.nxtbook.com/nxtbooks/pes/powerenergy_070814
https://www.nxtbook.com/nxtbooks/pes/powerenergy_050614
https://www.nxtbook.com/nxtbooks/pes/powerenergy_030414
https://www.nxtbook.com/nxtbooks/pes/powerenergy_010214
https://www.nxtbookmedia.com