NOGRR044

Title:	Clarification of a PSS In-Service and Improved Communication Process for Changes in PSS Status (formerly “Clarification of a PSS In-Service”)
Next Group:
Next Step:
Status:	Approved on 02/03/2011

Date	Gov Body		Next Steps
02/03/2011	TAC	Approved
01/13/2011	ROS	Recommended for Approval	TAC Consideration
12/15/2010	OWG	Recommended for Approval	ROS Consideration
10/20/2010	OWG	Deferred/Tabled	OWG Consideration
09/23/2010	OWG	Deferred/Tabled	OWG Consideration
08/18/2010	OWG	Deferred/Tabled	OWG Review
07/21/2010	OWG	Recommended for Approval	OWG IA Review

Date	Gov Body	Motion	Result	Against	Abstentions
02/03/2011	TAC	To approve NOGRR044 as amended by the 2/1/11 Luminant comments and as revised by TAC	Passed	0	0
01/13/2011	ROS	To recommend approval of NOGRR044 as amended by the 1/11/11 Austin Energy comments			1 IPM
12/15/2010	OWG	Consensus to endorse and forward the 7/21/10 OWG Recommendation Report as revised by OWG and the Impact Analysis for NOGRR044 to ROS
10/20/2010	OWG	Consensus to table NOGRR044 for one month
09/23/2010	OWG	Consensus to table NOGRR044 for one month
08/18/2010	OWG	Consensus to table NOGRR044 for one month
07/21/2010	OWG	Consensus to recommend approval of NOGRR044 as amended by the 7/19/10 ERCOT comments and as revised by OWG

Status:	Approved
Date Posted:	06/03/2010
Sponsor:	LCRA
Urgent:	No
Sections:	2.2.5, 2.2.6
Description:	This Nodal Operating Guide Revision Request (NOGRR) clarifies that a Power System Stabilizer (PSS) must be “On” and in an active MW range to be considered in service. This NOGRR also proposes language changes to improve the communication process for any change in PSS status.
Reason:	It is currently perceived that a PSS is deemed to be in service when a generator is On-Line and synchronized to the ERCOT Transmission Grid. However, that may not always be the case. For example, a PSS can be turned on or off via a control switch. Furthermore, if the PSS is turned on, it does not become active or responsive until the MW level surpasses the unit stability limit as it increases in MWs from zero MWs after synchronization to the ERCOT Transmission Grid. In the decreasing MW mode it will de-activate when it surpasses the defined Low Sustained Limit (LSL) while synchronized to the ERCOT Transmission Grid. The proposed revisions mitigate these concerns.