Task Force on Light Flicker

Meeting Minutes

Summer 2002 Meeting of IEEE PES

Chicago, IL

Tuesday, July 23, 2002

Larry Conrad opened the meeting by briefly previewing the agenda. The minutes of the IEEE PES Winter 2002 meeting held in New York City were approved as written. The TF was reminded that the minutes, as well as other TF documents, could be found on the TF web-site, grouper.ieee.org/groups/1453. Some documents on the web-site are protected, requiring an ID (wg1453) and password (flictage).

The 27 attendees made introductions.

Liaison Reports:

IEC 61000-4-15: Revisions to 61000-4-15, with contributions from P1453, passed unanimously in all countries. The document is now ready to go out in FDIS for final approval by the end of the year.

IEC 61000-3-7: The IEC would not permit free distribution of their Application Guide to this TF. The document is available for purchase from the IEC web-site: www.iec.ch.

P1547 (Distributed Generation): Larry Morgan reported that this TF has included various flicker requirements in the different versions of their draft. Our TF would discourage making P1547 a flicker standard or encouraging the use of flicker guidelines as currently given in IEEE 519 or the Red Book. They have Draft 10 ready to go out for ballot.

CIGRE: Erich reported that their next meeting in August would be to work on the flickermeter test protocol. They hope to wrap this up at that meeting.

Comments on Draft 3A:

Prior to this meeting, Draft 3A was sent to all TF members via e-mail. A large number of e-mails responses were received, which Larry collected into one document, which was sent to all TF members. Also, two marked up drafts were received. Larry stated that the purpose of this effort was to insure that the final product is technically correct and usable. He next explained the difference in a Standard and a Recommended Practice; the later being what this TF will ultimately ballot. A Recommended Practice lists good operating practice. It is a compilation of expert opinions where the core issue is the presentation of what has been useful for years. TF members then commented on their e-mail response. Motor starting is one issue for which there is still concern. Larry suggested that one way to address this might be to propose an absolute maximum voltage variation limit. Mark had a philosophical question concerning allowing a greater voltage drop and thus possibly creating more flicker complaints. Taking Pst values for home A/C units seems to produce values less than 1.0. Therefore, the IEC method does properly capture things that might be problematic. John Kennedy stated that he felt that a fixed upper voltage limit could be used to catch over-sized A/C units that have infrequent starts. Another question asked concerned whether a sag or infrequent voltage drop was or should be considered as flicker. Erich responded that these events are at the low end of the range of the flickermeter response. Dave commented that a customer might not notice the correlation between an A/C unit starting and his lights blinking. A question was then posed as to whether the old GE curve should be included in an Annex to assist those in accessing starting events. It was decided to add references to show some history of voltage flicker, including the GE curve. These references would include AIEE, IEEE and IEC articles on the subject. Our document needs to also include a statement that the results are based on usage of a 60W incandescent bulb. A question that was asked concerned adding an additional Annex to cover the work PEAC has done on the effect of various types of lamps. This request will be investigated. After much discussion on the motor starting issue, it was decided that background information would be provided, either in an Annex or in references such that the user could decide the appropriate method. IEC 61000-3-3 has an absolute maximum limit. Some state utility commissions currently recognize the GE curve and having it referenced in an Annex would be a transitional means to move to the IEC method. An IEC tutorial was presented to cover positive reasons for moving to the IEC method. After a lengthy discussion, the TF reviewed the Hanson and Gilmer documents as well as all e-mail comments. Following the meeting, Larry and Reuben will consolidate the comments from this meeting into an updated Draft, which will be sent to TF members via e-mail. Following a short time to allow for additional comments from the TF, the Draft will be submitted to IEEE for balloting.

The next meeting of the TF will be at the 2003 Winter T&D meeting in Las Vegas, NV.