초록 ▼

Provided are methods for controlling operation of a voltage regulator of a single-phase of a three-phase power system to regulate a measured voltage. One of the methods includes recording a first elapsed time between detecting a first excursion of the measured voltage from an in-band area to an out-

Provided are methods for controlling operation of a voltage regulator of a single-phase of a three-phase power system to regulate a measured voltage. One of the methods includes recording a first elapsed time between detecting a first excursion of the measured voltage from an in-band area to an out-of-band area, and a first return of the measured voltage to the in-band area. The method also includes recording a second elapsed time period (dip period) between detecting the first return and a second excursion of the measured voltage from the in-band area to an out-of-band area. If the second elapsed time period is less than a predetermined dip time period, causing a tap position change of the voltage regulator upon expiration of a countdown period initiated upon detecting the first excursion, thereby adjusting the measured voltage to the in-band area while allowing a voltage drop of limited length.

대표청구항 ▼

What is claimed is: 1. An apparatus for controlling operation of a voltage regulator via a tap position change, the voltage regulator operatively coupled to a single-phase of a three-phase power system to regulate a measured voltage of the single-phase to an in-band area for delivery to a load, the

What is claimed is: 1. An apparatus for controlling operation of a voltage regulator via a tap position change, the voltage regulator operatively coupled to a single-phase of a three-phase power system to regulate a measured voltage of the single-phase to an in-band area for delivery to a load, the apparatus comprising: a means for deriving a digitized voltage stream representative of the measured voltage of the single-phase; and a microcontroller operatively coupled to the means for deriving the digitized voltage stream and configured to enable the tap position change, the microcontroller having a microprocessor and a memory operatively coupled to the microprocessor, the microcontroller being programmed to: start a countdown time period of a first timer upon detecting a first excursion of the measured voltage from the in-band area to an out-of-band area, upon detecting a first return of the measured voltage to the in-band area, record a first elapsed time of the first timer, reset the first timer to the countdown time period, and start a second timer, upon detecting a second excursion of the measured voltage from the in-band area to the out-of-band area, record a second elapsed time of the second timer, compare the second elapsed time to a predetermined dip time period, if the second elapsed time is less than the predetermined dip time period, start an adjusted countdown time period of the first timer, and if the second elapsed time is more than the predetermined dip time period, start the countdown time period of the first timer upon subsequent entry of the measured voltage into the out-of-bound area. 2. The apparatus of claim 1, wherein the microcontroller is further programmed to cause the tap position change of the voltage regulator upon expiration of the countdown time period if a second return of the measured voltage into the in-band area is not detected, the tap position change adjusting the measured voltage from the out-of-band area to the in-band area. 3. The apparatus of claim 1, wherein the microcontroller is further programmed to cause the tap position change of the voltage regulator upon expiration of the adjusted countdown time period if a second return of the measured voltage into the in-band area is not detected, the tap position change adjusting the measured voltage from the out-of-band area to the in-band area. 4. The apparatus of claim 1, wherein the adjusted countdown time period is equal to the countdown time period of the first timer minus a sum of the first elapsed time and the second elapsed time. 5. The apparatus of claim 1, wherein the in-band area is adjustable between a first voltage value and a second voltage value, and wherein the out-of-band area is above the first voltage value. 6. The apparatus of claim 1, wherein the in-band area is adjustable between a first voltage value and a second voltage value, and wherein the out-of-band area is below the second voltage value. 7. An apparatus for controlling operation of a voltage regulator via a tap position change, the voltage regulator operatively coupled to a single-phase of a three-phase power system to regulate a measured voltage of the single-phase to an in-band area for delivery to a load, the apparatus comprising: a means for deriving a digitized voltage stream representative of the measured voltage of the single-phase; and a microcontroller operatively coupled to the means for deriving the digitized voltage stream, the microcontroller having a microprocessor and a memory operatively coupled to the microprocessor, the microcontroller being programmed to: start a countdown time period of a first timer upon detecting a first excursion of the measured voltage from the in-band area to an out-of-band area, upon detecting a first return of the measured voltage to the in-band area, start a second timer, and upon detecting a second excursion of the measured voltage from the in-band area to the out-of-band area, record a dip time of the second timer, the dip time based on a time elapsed between the first return and the second excursion, compare the dip time to a predetermined dip time period, and if the dip time is less than the predetermined dip time period and if a second return of the measured voltage to the in-band area is not detected, cause the tap position change of the voltage regulator upon expiration of the countdown time period, the tap position change adjusting the measured voltage from the out-of-band area to the in-band area. 8. The apparatus of claim 7, wherein the microcontroller is further programmed to cause the first timer to reset and begin the countdown time period if the dip time is more than the predetermined dip time period. 9. The apparatus of claim 7, wherein the in-band area is adjustable between a first voltage value and a second voltage value, and wherein the out-of-band area is above the first voltage value. 10. The apparatus of claim 7, wherein the in-band area is adjustable between a first voltage value and a second voltage value, and wherein the out-of-band area is below the second voltage value. 11. An apparatus for controlling operation of a voltage regulator via a tap position change, the voltage regulator operatively coupled to a single-phase of a three-phase power system to regulate a measured voltage of the single-phase to an in-band area for delivery to a load, the apparatus comprising: a means for deriving a digitized voltage stream representative of the measured voltage of the single-phase; and a microcontroller operatively coupled to the means for deriving the digitized voltage stream, the microcontroller having a microprocessor and a memory operatively coupled to the microprocessor, the microcontroller being programmed to: start a countdown time period upon detecting a first excursion of the measured voltage from the in-band area to an out-of-bands area, periodically sample and store the digitized voltage stream as a plurality of measured voltage samples, upon expiration of the countdown time period, calculate a measured percentage time based on the plurality of measured voltage samples stored during the countdown window, and compare the measured percentage time to a first threshold percentage time value, the comparison of the measured percentage time to the first threshold percentage time value determinative of whether the tap position change of the voltage regulator is needed. 12. The apparatus of claim 11, wherein the microcontroller is further programmed to cause the tap position change if the first threshold percentage time value comprises an out-of-band percentage value and if the measured percentage time is greater than the first threshold percentage time value, the tap position change adjusting the measured voltage from the out-of-band area to the in-band area. 13. The apparatus of claim 11, wherein the microcontroller is further programmed to cause the tap position change if the first threshold percentage time value comprises an in-band percentage value and if the measured percentage time is less than the first threshold percentage time value, the tap position change adjusting the measured voltage from the out-of-band area to the in-band area. 14. The apparatus of claim 11, wherein the microcontroller is further programmed to: compare the measured percentage time to a second threshold percentage time value if the measured percentage time is less than the first threshold percentage time value; and if the measured percentage time is more than the second threshold percentage time value, initiate a moving window, periodically sample and store the digitized voltage stream as another plurality of measured voltage samples over the moving window, continuously calculate the measured percentage time based on the another plurality of measured voltage samples, and compare the measured percentage time to the first threshold percentage time value and the second threshold percentage time value, the comparison determinative of whether the tap position change of the voltage regulator is needed. 15. The apparatus of claim 14, wherein the microcontroller is further programmed to: cause the tap position change if the measured percentage time is greater than the first threshold percentage time value; and reset the countdown time period if the measured percentage time is less than the second threshold percentage time value. 16. The apparatus of claim 14, wherein the microcontroller is further programmed to: cause the tap position change if the measured percentage time is less than the first threshold percentage time value; and reset the countdown time period if the measured percentage time is greater than the second threshold percentage time value. 17. The apparatus of claim 11, wherein a measured voltage sample of the plurality of measured voltage samples is stored as a binary one value if the measured voltage is in the out-of-band area, and wherein measured voltage sample is stored as a binary zero value if the measured voltage is in the in-band area. 18. The apparatus of claim 11, wherein the in-band area is adjustable between a first voltage value and a second voltage value, and wherein the out-of-band area is above the first voltage value. 19. The apparatus of claim 11, wherein the in-band area is adjustable between a first voltage value and a second voltage value, and wherein the out-of-band area is below the second voltage value. 20. The apparatus of claim 11, wherein the measured percentage time equals a percentage of time over the countdown time period that the measured voltage in is the out-of-band area. 21. The apparatus of claim 11, wherein the measured percentage time equals of percentage of time over the countdown time period that the measured voltage in is the in-band area. 22. A method for controlling operation of a voltage regulator via a tap position change, the voltage regulator operatively coupled to a single-phase of a three-phase power system to regulate a measured voltage of the single-phase to an in-band area for delivery to a load, the method comprising: deriving a digitized voltage stream representative of the measured voltage of the single-phase; starting a countdown time period of a first timer upon detecting a first excursion of the measured voltage from the in-band area to an out-of-band area; upon detecting a first return of the measured voltage to the in-band area, recording a first elapsed time of the first timer based on a time elapsed between the first excursion and the first return, resetting the first timer to the countdown time period, and starting a second timer; and upon detecting a second excursion of the measured voltage from the in-band area to the out-of-band area, recording a second elapsed time of the second timer based on a time elapsed between the first return and the second excursion, comparing the second elapsed time to a predetermined dip time period, starting an adjusted countdown time period of the first timer if the second elapsed time is less than the predetermined dip time period, and starting the countdown time period of the first timer upon a subsequent entry of the measured voltage into the out-of-bound area if the second elapsed time is more than the predetermined dip time period. 23. The method of claim 22, further comprising causing the tap position change of the voltage regulator upon expiration of the countdown time period if a second return of the measured voltage into the in-band area does not occur, the tap position change adjusting the measured voltage from the out-of-band area to the in-band area. 24. The method of claim 22, further comprising causing the tap position change of the voltage regulator upon expiration of the adjusted countdown time period if a second return of the measured voltage into the in-band area does not occur, the tap position change adjusting the measured voltage from the out-of-band area to the in-band area. 25. The method of claim 22, wherein the adjusted countdown time period is equal to the countdown time period of the first timer minus a sum of the first elapsed time and the second elapsed time. 26. The method of claim 22, wherein the in-band area is adjustable between a first voltage value and a second voltage value, and wherein the out-of-band area is above the first voltage value. 27. The method of claim 22, wherein the in-band area is adjustable between a first voltage value and a second voltage value, and wherein the out-of-band area is below the second voltage value. 28. A method for controlling operation of a voltage regulator via a tap position change, the voltage regulator operatively coupled to a single-phase of a three-phase power system to regulate a measured voltage of the single-phase to an in-band area for delivery to a load, the method comprising: deriving a digitized voltage stream representative of the measured voltage of the single-phase; starting a countdown time period upon detecting a first excursion of the measured voltage from the in-band area to an out-of-band area; upon detecting a first return of the measured voltage to the in-band area, starting a time count; and upon detecting a second excursion of the measured voltage from the in-band area to the out-of-band area, terminating the time count, and if the time count is less than a predetermined dip time period and if there is not a second return of the measured voltage to the in-band area, causing the tap position change of the voltage regulator upon expiration of the countdown time period to adjust the measured voltage from the out-of-band area to the in-band area. 29. The method of claim 28, further comprising restarting the countdown time period upon the second excursion if the time count is more than the predetermined dip time period. 30. The apparatus of claim 28, wherein the in-band area is adjustable between a first voltage value and a second voltage value, and wherein the out-of-band area is above the first voltage value. 31. The apparatus of claim 28, wherein the in-band area is adjustable between a first voltage value and a second voltage value, and wherein the out-of-band area is below the second voltage value. 32. A method for controlling operation of a voltage regulator via a tap position change, the voltage regulator operatively coupled to a single-phase of a three-phase power system to regulate a measured voltage of the single-phase to an in-band area for delivery to a load, the method comprising: deriving a digitized voltage stream representative of the measured voltage of the single-phase; starting a countdown time period upon detecting a first excursion of the measured voltage from the in-band area to an out-of-band area; periodically sampling and storing the digitized voltage stream as a plurality of measured voltage samples; upon expiration of the countdown time period, calculating a measured percentage time based on the plurality of measured voltage samples stored during the countdown window; and comparing the measured percentage time to a first threshold percentage time value, the comparison of the measured percentage time to the first threshold percentage time value determinative of whether the tap position change of the voltage regulator is needed. 33. The method of claim 32, further comprising causing the tap position change if the first threshold percentage time value comprises an out-of-band percentage value and if the measured percentage time is greater than the first threshold percentage time value, the tap position change adjusting the measured voltage from the out-of-band area to the in-band area. 34. The method of claim 32, further comprising causing the tap position change if the first threshold percentage time value comprises an in-band percentage value and if the measured percentage time is less than the first threshold percentage time value, the tap position change adjusting the measured voltage from the out-of-band area to the in-band area. 35. The method of claim 32, further comprising: comparing the measured percentage time to a second threshold percentage time value if the measured percentage time is less than the first threshold percentage time value; and if the measured percentage time is more than the second threshold percentage time value, initiating a moving window, periodically sampling and storing the digitized voltage stream as another plurality of measured voltage samples over the moving window, continuously calculating the measured percentage time based on the another plurality of measured voltage samples, and comparing the measured percentage time to the first threshold percentage time value and the second threshold percentage time value, the comparison determinative of whether the tap position change of the voltage regulator is needed. 36. The method of claim 35, further comprising: causing the tap position change if the measured percentage time is greater than the first threshold percentage time value; and resetting the countdown time period if the measured percentage time is less than the second threshold percentage time value. 37. The method of claim 35, further comprising: causing the tap position change if the measured percentage time is less than the first threshold percentage time value; and resetting the countdown time period if the measured percentage time is greater than the second threshold percentage time value. 38. The method of claim 32, wherein a measured voltage sample of the plurality of measured voltage samples is stored as a binary one value if the measured voltage is in the out-of-band area, and wherein the measured voltage sample is stored as a binary zero value if the measured voltage is in the in-band area. 39. The method of claim 32, wherein the measured percentage time equals a percentage of time over the countdown time period that the measured voltage is the out-of-band area. 40. The method of claim 32, wherein the measured percentage time equals of percentage of time over the countdown time period that the measured voltage is in the in-band area. 41. A method for controlling operation of a voltage regulator via a tap position change, the voltage regulator operatively coupled to a single-phase of a three-phase power system to regulate a measured voltage of the single-phase to an in-band area for delivery to a load, the method comprising: (a) recording a first elapsed time period between detecting a first excursion of the measured voltage from the in-band area to an out-of-band area and detecting a first return of the measured voltage to the in-band area, the first excursion initiating a first countdown time period; (b) recording a second elapsed time period between detecting the first return of the measured voltage to the in-band area and a second excursion of the measured voltage from the in-band area to an out-of-band area; (c) comparing the second elapsed time period to a predetermined dip time period; and (d) if the second elapsed time period is less than the predetermined dip time period and if a second return of the measured voltage to the in-band area is not detected, causing the tap position change of the voltage regulator upon expiration of the first countdown time period, the tap position change adjusting the measured voltage from the out-of-band area to the in-band area. 42. The method of claim 41, further comprising repeating steps (a)-(d) upon detecting the second return of the measured voltage to the in-band area. 43. The method of claim 41, wherein if the second elapsed time period is greater than the predetermined dip time period and if a second return of the measured voltage to the in-band area is not detected, causing the tap position change of the voltage regulator upon expiration of a second countdown time period initiated upon the second excursion of the measured voltage, the second countdown time period equal to the first countdown time period. 44. The method of claim 41, wherein the in-band area is adjustable between a first voltage value and a second voltage value, and wherein the out-of-band area is above the first voltage value. 45. The method of claim 41, wherein the in-band area is adjustable between a first voltage value and a second voltage value, and wherein the out-of-band area is below the second voltage value. 46. A method for controlling operation of a voltage regulator via a tap position change, the voltage regulator operatively coupled to a single-phase of a three-phase power system to regulate a measured voltage of the single-phase to an in-band area for delivery to a load, the method comprising: upon detecting a first excursion of the measured voltage from the in-band area to an out-of-band area, periodically sampling and storing a plurality of measured voltage samples representative of a plurality of the measured voltages of the single-phase; and upon expiration of a countdown time period started upon detecting the first excursion, comparing a calculated value to a first threshold percentage time value to determine whether the tap position change of the voltage regulator is needed, the calculated value based on a comparison of the plurality of measured voltage samples stored during the countdown time period. 47. The method of claim 46, wherein the calculated value comprises a measured percentage time. 48. The method of claim 47, further comprising causing the tap position change of the voltage regulator if the first threshold percentage time value comprises an out-of-band percentage value and if the measured percentage time is greater than the first threshold percentage time value, the tap position change adjusting the measured voltage from the out-of-band area to the in-band area. 49. The method of claim 47, further comprising causing the tap position change of the voltage regulator if the first threshold percentage time value comprises an in-band percentage value and if the measured percentage time is less than the first threshold percentage time value, the tap position change adjusting the measured voltage from the out-of-band area to the in-band area. 50. The method of claim 47, further comprising: if the measured percentage time is less than the first threshold percentage time value and more than a second threshold percentage time value, periodically sampling and storing another plurality of measured voltage samples over a moving window, continuously calculating the measured percentage time based on the another plurality of measured voltage samples, and comparing the measured percentage time to the first threshold percentage time value and the second threshold percentage time value to determine whether the tap position change of the voltage regulator is needed. 51. The method of claim 50, further comprising: causing the tap position change if the measured percentage time is greater than the first threshold percentage time value; and restarting the countdown time period upon detecting a next excursion of the measured voltage from the in-band area to an out-of-band area if the measured percentage time is less than the second threshold percentage time value. 52. The method of claim 50, further comprising: causing the tap position change if the measured percentage time is less than the first threshold percentage time value; and restarting the countdown time period upon detecting a next excursion of the measured voltage from the in-band area to an out-of-band area if the measured percentage time is greater than the second threshold percentage time value. 53. The method of claim 47, wherein the measured percentage time equals a percentage of time over the countdown time period that the measured voltage in is the out-of-band area. 54. The method of claim 47, wherein the measured percentage time equals a percentage of time over the countdown time period that the measured voltage in is the in-band area. 55. The method of claim 46, wherein the calculated value comprises an averaged measured voltage value. 56. The method of claim 55, wherein the microcontroller is further programmed to cause the tap position change of the voltage regulator if the averaged measured voltage value is greater than the first threshold voltage value, the tap position change adjusting the measured voltage from the out-of-band area to the in-band area. 57. The method of claim 55, wherein the microcontroller is further programmed to: compare the averaged measured voltage value to a second threshold voltage value if the averaged measured voltage value is not greater than the first threshold voltage value; and if the averaged measured voltage value is less than the second threshold voltage value, cause the tap position change to adjust the measured voltage from the out-of-band area to the in-band area. 58. The method of claim 57, wherein the microcontroller is further programmed to reset the countdown time period if the averaged measured voltage value is greater than the second threshold voltage value and less than the first threshold value. 59. The method of claim 57, wherein first threshold voltage value is equal to an upper voltage of the in-band area and wherein the second threshold voltage value is equal to a lower voltage of the in-band area. 60. The method of claim 57, wherein first threshold voltage value is equal to a lower voltage of the out-of-band area above the in-band area and wherein the second threshold voltage value is equal to a higher voltage of the out-of-band area below the in-band area. 61. The method of claim 55, wherein the averaged measured voltage value is equal to a sum of the magnitudes of the plurality of measured voltage samples, divided by the number of the plurality of measured voltage samples. 62. The method of claim 46, wherein the in-band area is adjustable between a first voltage value and a second voltage value, and wherein the out-of-band area is above the first voltage value. 63. The method of claim 46, wherein the in-band area is adjustable between a first voltage value and a second voltage value, and wherein the out-of-band area is below the second voltage value.