Technical criteria for wind farm power stations connected to the transmission system - Wind Power Integration: Connection and System Operational Aspects - page 280

characteristic. (This is an absolute minimum and if the
WFPS can offer a larger response it should do so.)

2. Secondary Response capability of the WFPS (avail-

able by 30 seconds and sustained): 100% of the expec-
ted MW Output value based upon droop characteristic.

(b) This Fast Acting proportional governor should be equipped

with controls which allow the droop to be set independently
in the range 2-20% above and below 50.0 Hz. A Governor
Dead Band within which no control will be exercised must
be capable of being set with a lower limit between 49.0 and
50.0 Hz in steps of 0.05 Hz and an upper limit between
50.0 and 51.0 Hz in steps of 0.05 Hz. Whilst responding to
Frequency excursions on the System the change in Output
of the Controllable WFPS shall be at the Frequency
Response Ramp Rate . In addition a high Frequency trip
facility must be provided capable of being set in the range
51.0-52.0 Hz in steps of 0.1 Hz. Unless the Developer/
Generator is notified otherwise by the TSO ,the Governor
Droop , Governor Dead Band and high Frequency trip
settings shall be as specified by the TSO from time to time
in the WFPS Settings Schedule published on the website
(or such other place or by such other means as may be
notified to the Developer / Generator from time to time).
Where a Controllable WFPS becomes isolated from the
rest of the Transmission System the Controllable WFPS
must immediately detect the condition and shut itself down.

(c) Under certain System conditions the TSO may require a

Controllable WFPS to operate below its maximum instan-
taneous Output on a droop setting to be set in the range
2-20%. In this mode of operation the Controllable WFPS
will be providing some of the System reserve. The Con-
trollable WFPS controller must be capable of being set to
operate in a constrained manner within the range of at least
50-100% of maximum instantaneous Output . This mode is
known as Frequency Sensitive Mode .

CC.S2.5.3

(a) Each Controllable WFPS must be fitted with a Fast Acting

control system capable of being switched to control the
Controllable WFPS voltage, Power Factor or the Reactive
Power output at the Connection Point . These control modes
must maintain the voltage at the Connection Point within a
voltage band as specified within the Connection Agreement
or other agreement for the particular site, and in any case