Wind Farm Protection

1. Wind Farm Protection Automation, Lattes

2. Frequency Voltage Residual Voltage 81U/O 27/59 50/51N O/C & E/F 59N df/dt ROCOF Voltage Vector Shift dV NPS Voltage NPS O/C 47/46 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 - <10MVA,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 Generators<5MW to Systems <20kV

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 REC’s supply unless all phases of the REC’s 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 REC’s system in the event of loss of one or more phases of the REC’s 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 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 Permanent Parallel Operation LV Generators HV Generators Protection required Export Small <150kV Medium 150-250kVA Large >250kVA No Export (2) (3) (3)

13. MiCOM P341 ApplicationsG59 Protection Equipment Protection Requirements for Private Generator Operating in Parallel with Electricity Board Network 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 Notes: (1) Protection for generators (2) Sensitive Relay (3) Optional (4) Application dependant Short Term ‘Test’ Parallel Operation (5 min max) LV Generators HV Generators Protection required Small <150kV Medium 150-250kVA Large >250kVA 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 df/dt = Two consecutive calculations must give a result above the setting threshold before a trip decision can be initiated F - f 3 cycle n n - 3 cycle - MiCOM P341 Generator Protection -

21. MiCOM P341 ApplicationsG59 Protection Equipment df/dt+t: Time Delayed ROCOF t Start Pick up cycles Trip f Time delay df/dt Setting