Method and apparatus for detecting unintentional islanding of utility grid

1. A method for identifying an islanding event in a utility grid, said method comprising the steps of:

generating an analog user defined control signal;

applying said user defined control signal to a distributed resource, said distributed resource interconnected to said utility grid while providing power flow into a load;

utilizing said user defined control signal to incrementally alter at least one operating parameter, said at least one operating parameter being a speed, a frequency, or a real power control of said distributed resource and

utilizing a protective mechanism to separate said distributed resource from said utility grid, thereby terminating said islanding event while said distributed resource continues to provide power flow to said load.

2. The invention of claim 1 wherein said step of utilizing said user defined control signal to alter said at least one operating parameter further includes the step of exposing said islanding event in said utility grid.

3. The invention of claim 1 further comprising the step of

monitoring at least one parameter of said distributed resource to determine if said parameter exceeds a user-defined activation threshold; and

applying said user-defined control signal to said distributed source if said parameter exceeds said user-defined activation threshold.

4. The invention of claim 3 further comprising the step of utilizing a protective mechanism to separate said distributed resource from said power grid if said control signal causes said monitored parameter to exceed said user-defined threshold.

5. The invention of claim 3 wherein said user-defined activation threshold comprises a frequency threshold.

6. The invention of claim 5 further comprising the step of determining if said frequency exceeds an upper activation threshold.

7. The invention of claim 5 further comprising the step of

setting an initial ramp direction of said user defined control signal in a predefined direction if said frequency exceeds said upper activation threshold.

8. The invention of claim 5 further comprising the step of

determining if said frequency exceeds a lower activation threshold.

9. The invention of claim 8 further comprising the step

setting an initial ramp direction of said user defined control signal in a predefined direction if said frequency exceeds said lower activation threshold.

10. The invention of claim 1 where said distributed resource comprises a synchronous power source.

11. The invention of claim 10 wherein said synchronous power source comprises a generator.

12. The invention of claim 1 wherein said control signal comprises at least one incremental pulse.

13. The invention of claim 1 wherein said user defined control signal defines a duty cycle.

14. The invention of claim 1 wherein said user defined control signal defines an update rate.

15. The invention of claim 1 wherein said user defined control signal defines a ramp rate.

16. The invention of claim 1 wherein said user defined control signal defines a timeout duration.

17. The invention of claim 1 wherein said user defined control signal defines a peak disturbance value.

18. The invention of claim 17 wherein said peak disturbance value defines a dwell time.

19. The invention of claim 17 wherein said peak disturbance value comprises a positive peak disturbance value.

20. The invention of claim 17 wherein said peak disturbance value comprises a negative peak disturbance value.

21. A system for identifying a distributed resource islanding event in a utility grid, said apparatus comprising:

a distributed resource at a synchronous state, said distributed resource coupled to said utility grid and providing power to a load; and

an analog user defined control signal applied to said distributed resource,

wherein said control signal is used to incrementally alter at least one operating parameter of said distributed resource, said at least one operating parameter being a speed, a frequency, or a real power control of said distributed resource, and

a protective mechanism that separates said distributed resource from said utility grid, thereby terminating said islanding event while said distributed resource continues to provide power to said load.

22. An analog user definable unintentional islanding system control signal, said system control signal comprising:

a first signal defining a first peak disturbance,

a second signal defining a second peak disturbance,

wherein said user definable unintentional islanding control signal is used to incrementally alter at least one operating parameter of a distributed resource, that provides power to a load, said at least one operating parameter being a speed, a frequency, or a real power control of said distributed resource, and

a protective mechanism that separates said distributed resource from said utility grid, thereby terminating said islanding event while said distributed resource continues to provide power to said load.

23. The invention of claim 22 further comprising

a timeout duration, said timeout duration terminating the output of said control signal upon said timeout duration expiration.

24. The invention of claim 22 wherein said first signal defines a first ramp rate.

25. The invention of claim 22 wherein said second signal defines a second ramp rate.

26. The invention of claim 22 where said first peak disturbance defines a first dwell time.

27. The invention of claim 22 where said second peak disturbance defines a second dwell time.

28. The invention of claim 22 further comprising an update rate,

said update rate defining an amount of time between a first application of said control signal and a second application of said control signal for altering at least one operating parameter of said distributed resource.