Interconnected Electric System Protection Requirements

Key Dates and Materials

May 7, 2024 | Roundtable Technical Discussion 2 Invitation posted

April 4, 2024 | Initial Issues List Written Consultation Stakeholder Comments posted

Purpose

The AESO is initiating a new business engagement to review Section 503.15 of the ISO rules, Interconnected Electric System Protection Requirements (“Interconnected Electric System Protection Requirements”). Desired outcomes of this engagement include:

  1. Identifying cost-reduction opportunities associated with design and application of interconnected electric system protection and control, and maintaining reliability and system resiliency in transmission facilities.
  2. Identifying protection and control requirements on new power system elements and topology such as IBRs and T-tap to ensure the efficiency, reliability and performance of the transmission system.
  3. Discussing with stakeholders the existing interconnected electric system protection technical requirements, with a goal of reducing waiver and variance requests in the future; and
  4. Exploring and discussing recent changes in technology and standards relating to protection and control philosophy and scheme.

The AESO has developed the Initial Issues List for stakeholders’ consideration and a series of Stakeholder Feedback Survey questions that will inform the AESO’s determination of the scope of the engagement. The AESO intends to host roundtable technical discussions throughout 2024 and invites interested stakeholders to participate. Given the subject matter of the engagement, the AESO envisions active participation from the following parties operating in Alberta:

  • Transmission facility owners;
  • Generating facility owners;
  • Owners of all types of industrial systems (i.e., not limited to industrial systems designated by the Alberta Utilities Commission) with transmission facilities; and
  • Other parties who, in the AESO's view, can provide valuable input during the roundtable discussions.

To promote process efficiency, participation in the roundtable technical discussions will allow for one primary representative and one delegate. If both the primary and delegate representatives are available, both representatives may attend.

If, as a result of this engagement, the AESO determines that changes to AESO authoritative documents are required, these will be addressed through the applicable processes for developing ISO rules and Alberta Reliability Standards.

Background


Further to the approval in Alberta Utilities Commission Decision 28176-D01-2023 on June 13, 2023, previous effective Section 502.3 of the ISO rules, Interconnected Electric System Protection Requirements (“Section 502.3”) was transitioned into and succeeded by Section 503.15, Interconnected Electric System Protection, effective April 1, 2024.

To ensure a consistent approach to protection systems design and to facilitate a fair, cost effective, and reliable transmission system within Alberta, Section 503.15 addresses the minimum technical requirements of protection philosophy, schemes, and applications for each system element in the Alberta Bulk Electrical System.

Section 502.3 was drafted in 2012, and the technical requirements have not changed substantively since then. In 2019, the AESO collaborated with facility owners to review completed projects and future development plans regarding digital substation technologies in Alberta. The participants' experiences and plans helped the AESO assess potential barriers in Section 502.3. In 2021, the AESO conducted another informal survey associated with Section 502.3 to help identify cost reduction opportunities.

Given the evolvement in technology and system generations being observed, the AESO believes a fresh engagement on interconnected electric system protection is needed at this time. Therefore, the AESO is initiating this new engagement in Spring 2024.



Key Dates and Materials

May 7, 2024 | Roundtable Technical Discussion 2 Invitation posted

April 4, 2024 | Initial Issues List Written Consultation Stakeholder Comments posted

Purpose

The AESO is initiating a new business engagement to review Section 503.15 of the ISO rules, Interconnected Electric System Protection Requirements (“Interconnected Electric System Protection Requirements”). Desired outcomes of this engagement include:

  1. Identifying cost-reduction opportunities associated with design and application of interconnected electric system protection and control, and maintaining reliability and system resiliency in transmission facilities.
  2. Identifying protection and control requirements on new power system elements and topology such as IBRs and T-tap to ensure the efficiency, reliability and performance of the transmission system.
  3. Discussing with stakeholders the existing interconnected electric system protection technical requirements, with a goal of reducing waiver and variance requests in the future; and
  4. Exploring and discussing recent changes in technology and standards relating to protection and control philosophy and scheme.

The AESO has developed the Initial Issues List for stakeholders’ consideration and a series of Stakeholder Feedback Survey questions that will inform the AESO’s determination of the scope of the engagement. The AESO intends to host roundtable technical discussions throughout 2024 and invites interested stakeholders to participate. Given the subject matter of the engagement, the AESO envisions active participation from the following parties operating in Alberta:

  • Transmission facility owners;
  • Generating facility owners;
  • Owners of all types of industrial systems (i.e., not limited to industrial systems designated by the Alberta Utilities Commission) with transmission facilities; and
  • Other parties who, in the AESO's view, can provide valuable input during the roundtable discussions.

To promote process efficiency, participation in the roundtable technical discussions will allow for one primary representative and one delegate. If both the primary and delegate representatives are available, both representatives may attend.

If, as a result of this engagement, the AESO determines that changes to AESO authoritative documents are required, these will be addressed through the applicable processes for developing ISO rules and Alberta Reliability Standards.

Background


Further to the approval in Alberta Utilities Commission Decision 28176-D01-2023 on June 13, 2023, previous effective Section 502.3 of the ISO rules, Interconnected Electric System Protection Requirements (“Section 502.3”) was transitioned into and succeeded by Section 503.15, Interconnected Electric System Protection, effective April 1, 2024.

To ensure a consistent approach to protection systems design and to facilitate a fair, cost effective, and reliable transmission system within Alberta, Section 503.15 addresses the minimum technical requirements of protection philosophy, schemes, and applications for each system element in the Alberta Bulk Electrical System.

Section 502.3 was drafted in 2012, and the technical requirements have not changed substantively since then. In 2019, the AESO collaborated with facility owners to review completed projects and future development plans regarding digital substation technologies in Alberta. The participants' experiences and plans helped the AESO assess potential barriers in Section 502.3. In 2021, the AESO conducted another informal survey associated with Section 502.3 to help identify cost reduction opportunities.

Given the evolvement in technology and system generations being observed, the AESO believes a fresh engagement on interconnected electric system protection is needed at this time. Therefore, the AESO is initiating this new engagement in Spring 2024.



  • CLOSED: This survey has concluded.

    Request for Comment | Interconnected Electric System Protection Requirements

    The AESO is seeking stakeholder input and feedback to inform the AESO’s determination of the scope of the engagement on interconnected electric system protection requirements. 

    Instructions 

    1. To submit your responses, you will need to be registered and signed in on the AESO Engage platform. 
    2. Please click on the "Submit Stakeholder Feedback" box below to begin the survey and provide your specific comments. 
    3. Please submit one completed survey per organization. 
    4. All responses will be shared on AESO Engage. 
    5. Responses are due on or before April 2, 2024.

    Survey Questions for Stakeholders: 

    1. Proper coordination with adjacent protection systems: Should any specific scenarios need to be identified where minor miscoordinations can be acceptable? Please provide examples of specific scenarios.
    2. Proper coordination with adjacent protection systems: Should coordination consider a broader rule that supports a more rigorous area review?
    3. Proper coordination with adjacent protection systems: Should protection settings be designed to be coordinated always for a single contingency?
    4. Proper coordination with adjacent protection systems: Should the AESO explore requirements for protection coordination during intentional islands which may occur as part of a system restoration plan or N-1-1 topologies in the AIES?
    5. Requirement for diversified vendors on major protective relays: Should the AESO leverage a single vendor for both protection systems? Please provide comments on the conditions under which the AESO should allow a single vendor.
    6. Protection relays operate time: Should the AESO continue to specify each protection relay maximum operate time? Alternatively, the AESO can set the maximum acceptable fault clearing time (FCT) per voltage level
    7. CT/VT secondary connection redundancy: Should the AESO add provisions to exempt some applications for CT/VT redundancy?
    8. Event capture: Should the AESO align the ISO rule requirements for event recording with Alberta Reliability Standard PRC-002-AB-2, Disturbance Monitoring and Reporting Requirements?
    9. Ground fault resistance coverage: Should the AESO clarify the expected FCT of 5Ω ground fault resistance coverage?
    10. Ground fault resistance coverage: Is 5Ω fault resistance coverage applicable to most ground faults coverage?
    11. Auto-reclosing prohibition: Should the AESO consider any other scenarios for this requirement? Please provide examples of potential scenarios.
    12. Synchronism check relaying: Should the AESO add provisions to exempt the sync-check function for 240kV lines directly connected with IBRs? 
    13. Synchronism check relaying: Should the AESO consider the expansion of sync-check requirements on 138 kV breakers for implementation whenever line PT is present? Please provide examples of potential scenarios.
    14. Synchronism check relaying: Should the AESO explore sync-check requirements for system restoration?
    15. Protection system communications: Should the AESO expand on communication requirements for tele-protection?
    16. Multi-terminal lines: The AESO will address multi-terminal line beyond 3 terminals and all remote substation checks required as part of adding a tap. Please provide your thoughts on any potential challenges for multi-terminal lines.
    17. 500kV protection system setting verification: Should the AESO clarify requirements for RTDS testing and what changes to existing facilities would trigger the new RTDS testing requirements? Please provide your thoughts on areas requiring clarification.
    18. Substation shunt capacitor banks: Should the AESO review this requirement depending on the specific capacitor bank configuration?
    19. Breaker failure protection: Should the AESO clarify remote breakers DTT and their redundancy requirements?
    20. Substation transformer ended lines: Under what conditions should direct-transfer-tripping of the remote breaker be required for transformer ended lines? Please provide examples.
    21. Protection from Interconnected Electric System faults:  Should undervoltage function be required to trip the interconnected breaker as backup for any aggregated generating facilities or distributed energy resources (DERs)? 
    22. Voltage protections at GFOs: The applicable voltage of voltage/frequency ride-through is specified at the point of connection. How should protection coordination be maintained to meet the ride-through requirements? Please provide your comments on the current implementation.
    23. IBRs Synchronizing: Should IBRs be required to identify synchronizer locations?
    24. IBRs Synchronizing: Should IBRs be required to have a synchronizer on each unit breaker?
    25. Transmission Synchronizing: Should the AESO explore requirements for synchronizer relays at the transmission level?
    26. Current desensitization: Are there any concerns that protective relays are suffering current desensitization due to supplemental grounding source being placed at front or adjacent area of existing relays?
    27. IBR model and short circuit study: Different simulation software provides different tools for fault calculation. Are there any concerns relating to inconsistent models affecting short-circuit study and protection coordination?
    28. IBR and protection effectiveness: Should the AESO provide directions relating to negative-sequence current injection by IBRs for unbalanced system faults?
    29. Remedial action scheme (RAS)/Anti-islanding scheme (AIS) implementation: Should the AESO provide requirements for RAS/AIS implementation when using protective relays?
    30. Point-on-Wave (POW): The ISO rules are currently silent on POW installation. Is there a need for the AESO to implement requirements on this matter?
    31. Issues List: Do you have comments on the Initial Issues List?  If yes, please elaborate briefly.
    Submit Stakeholder Feedback
Page last updated: 07 May 2024, 02:53 PM