Task Force on Light Flicker

Meeting Minutes

IEEE PES Winter Power Meeting, New York, NY

Tuesday, Feb. 2, 1999

  1. Larry Conrad opened the meeting, there were 19 in attendance.
  2. After a brief introduction of those present, Larry reminded the TF that the minutes for previous TF meetings, along with other TF documents, are posted on the web-site. Some of the documents are password protected with access available only to TF members. The minutes from the St. Louis IAS Annual meeting were approved as posted on the web-site.
  3. Larry handed out the latest draft of IEC 61000-4-15, which he received at the IEC meeting in Paris. This proposal contains a recommended additional test point for the flickermeter classifier. The proposal suggested that the classifier stage for 50Hz flickermeters be a 6th order Butterworth filter with a 35Hz corner frequency. For the 60Hz flickermeter, they suggested an 8th order Butterworth filter with a 56Hz corner frequency. These changes were recommended mainly to accommodate the testing of cooking plates in Europe. The latest draft also contained specifications for the 120V 60Hz system as suggested by this TF. A discussion followed as to the need for different filters for the 50-60Hz system flickermeters. Erich explained that the 8th order filter might be needed for the 60Hz system to remove the modulation component due to its closeness to the "carrier" frequency. The majority of attendees agreed they could see no reason to make the filters different or, if they were to be different, they should differ by a ratio between the 50-6 0Hz filters. As proposed, there appeared to be no ratio difference between the filter designs. Mark suggested that there was no need to change the standard for a single problem. Tom indicated that the European’s intent was mainly to check for compliance of appliances as opposed to the main North American intent of checking for compliance on the utility network. At this point, Roger led the group in a discussion into the background of acceptance testing on cooking plates. Larry reminded the group that the point of this whole discussion was to either accept or reject the technical change to the IEC meter specification. A question was then asked that if this change were not implemented, would the existing meters be obsolete? This was brought up as some meter manufacturers have gotten into trouble by not implementing the optional filters according to the standard. Erich discussed the difficulty of any meter meeting all the test points and asked if these measures are adequate assurance that any given manufacturers meter will give similar results. Mark stated that the standard is very specific as to the meter design and that some vendors are taking liberties in implementing the standard. Erich discussed the issue of the need for a standard but at the same time allowing leeway for vendors to use advance technology to implement the standard. Tom pointed out that the IEC did not give the end user a test protocol, just a list of test points. Many agreed that additional test points were needed to further verify meter compliance. Everyone still desired to coordinate with the IEC. It was further suggested that the problem was scalable and that by moving the corner frequency of the filters, the 50Hz and 60Hz meters could agree with each other. Larry summarized the discussion as follows:

In closing this discussion, Erich suggested that the TF prepare a paper to describe the meter validation process.

  1. Larry informed the TF that our PAR was in its fourth year and the group should consider extending it if the work could not be finished before its expiration. A motion was made by James and seconded by Erich to ask for a PAR extension. It was approved by the TF.
  2. Completion of the TF’s document P1453 was next discussed. It was agreed that Draft 2 would be ready by the PES Summer meeting. Roger suggested that a test procedure is a must so Larry suggested that it be placed in an informative annex. An official copy of the IEC document is needed to complete the Draft; Erich is to e-mail a copy to Larry. Larry and Mark will pursue writing the document for completion by the end of March. A balloting committee would then need to be put together consisting of members from lighting, manufacturing, utilities, and consulting. A preliminary list follows:
  3. Lighting: Warren Anderson

    Manufacturing: Alex McEchern, Peter Shah, Mike Marz

    Utilities: Gil Hensley, Reuben Burch

    Consulting: Erich Gunther, Tom Key, Mark Halpin

    As an action item, Erich will request additional test points when he attends the next UIE meeting.

  4. Mark discussed the tutorial for the PES Summer meeting. The title will be "IEEE Guidelines for Measuring Flicker." The deadline for submitting tutorial material to the IEEE is April 1st. To meet this deadline, Mark requested that all drafts be submitted to him by Feb. 26th. A proposed chapter outline along with presenters names follows:

Chap. 1: History and Prospective – Tom Key

Chap. 2: Introduction to Flicker and Modulation – Mike Marz

Chap. 3: Basic Meter Block Diagram – James Wikston

Chap. 4: Meter Outputs – Rich Bingham and Erich Gunther

Chap. 5: Shape Factor and Flicker Prediction – Roger Bergeron

Chap. 6: IEC 61000-3-7 – Mark Halpin

Chap. 7: Case Study – Furnace – James Wikston

Chap. 8: Case Study – Welders – Tom Key

Chap. 9: Case Study – Motor Start – Roger Bergeron

Chap. 10: Case Study - ????? – Larry Conrad

Chap. 11: Case Study - ????? – Rich Bingham

Chap. 12: Case Study - ????? – Reuben Burch

7. The next meeting will be held at the IEEE PES Summer Power meeting in Edmonton, Alberta.

8. The meeting adjourned at 10:00AM.