Download Stakeholder Comment and Rationale Form AESO AUTHORITATIVE DOCUMENT PROCESS Stakeholder Consultation Draft

Stakeholder Comment and Rationale Form
AESO AUTHORITATIVE DOCUMENT PROCESS
Stakeholder Consultation Draft
2012-08-14
Proposed New ISO Rules Section 502.3 Interconnected Electric System Protection Requirements (“New ISO Rules Section 502.3”)
Date of Request for Comment [yyyy/mm/dd]:
Period of Consultation [yyyy/mm/dd]:
2012/08/14
2012/08/14
Comments From:
AltaLink Management Ltd.
Date [yyyy/mm/dd]:
2012/09/14
through 2012/09/14
Contact:
Dale Reso
Phone:
403-267-3489
E-mail:
[email protected]
Listed below is the summary description of changes for the proposed new, removed or amended sections of the ISO rules. Please refer back to the Letter of Notice under the “Attachments to Letter of
Notice” section to view the actual proposed content changes to the ISO rules. Please place your comments / reasons for position underneath (if any).
1. ISO Rules
Stakeholder Comments and/or Alternate Proposal
AESO Replies
(a) Purpose of Proposed New ISO Rules Section 502.3
Proposed New ISO Rules Section 502.3 sets out the minimum technical protection
system requirements for the interconnected electric system.
In developing the New ISO Rules Section 502.3 the AESO has redrafted and
relocated content from the current AESO Protection Standard. In addition, in
developing New ISO Rules Section 502.3 the AESO is proposing changes as
outlined below, as a result of the review performed with the industry workgroup.
In the AESO’s opinion, these proposed changes improve the protection systems on
the Alberta interconnected electric system and ultimately the safe reliability
operation of the system.
The AESO is specifically seeking comments from stakeholders with respect to these
key changes. Please provide comments on :
1) Do you agree or disagree that the AESO has clearly and adequately
represented the key changes in proposed New ISO Rules Section 502.3? If
you disagree please provide your reasons and suggestions for improvement.
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1. Clarified applicability and the relationship of proposed New ISO
Rules Section 502.3 to a project’s Functional Specification will
be provided.
Subsections
1 to 5
AltaLink supports with language suggestions.
AltaLink recommends that the wording “functional
specification” be adjusted to “initial (i.e., first issue)
functional specification” in section 2 and subsection 3(1)
to provide further clarity.
AltaLink recommends that more details be provided
regarding the application of the Rule on existing
facilities. Although the application of the Rule on
existing facilities is discussed in the Information
Document, it is not clear how the AESO will define in
the functional specification (as it is not clear in the Rule)
when existing facilities need to meet the requirements of
the new Rule.
Subsection 1(c) states that the rule applies to “the legal
owner of a transmission facility with a rated voltage
equal to or greater than one hundred (100) kV;…”
However, the rule does not indicate if it only applies to
facilities connected at 100 kV or higher? AltaLink
recommends that the rule include a statement that
indicates that it applies to transmission facilities with a
rated voltage equal to or greater than one hundred
(100) kV.
2. Requirements for two protection systems and subcomponents
will be clarified.
Subsection
7
AltaLink supports this ISO requirement and has no
comment
3. Maximum protection relay operate times will be provided to
ensure transmission grade relays are utilized for new facilities.
Total clearing times will be addressed in the AESO’s upcoming
revision to the Planning Criteria.
Subsection
8
AltaLink supports with language suggestions.
AltaLink recommends that the wording in subsection
8(1), 8(2), 8(3), 8(4) be adjusted to “… the primary
protection relay must be specified such that the operate
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times…do not exceed…” to more closely align with
section 7.1 of ID 2012-004R.
4. Event capture for new facilities and the need for GPS time
synchronization will be provided.
Subsection
14
AltaLink supports with language suggestions.
AltaLink recommends that this requirement be amended
to indicate “it applies only on the addition of new power
system elements and not modifications or replacement
of existing protection systems.”
AltaLink also recommends that the reference to a global
positioning system clock be removed from 14(3). It is
recommended that the requirement be amended to
indicate accuracy to 1.0 ms of UTC. The method of
achieving the accuracy should be left to the discretion of
the legal owner of a transmission facility.
5. Auto Reclosing – At 240kV and higher voltages, single pole trip
and reclose will become the standard practice for new facilities.
At 240kV and higher voltages, no three (3) pole trip and reclose
will be required. The success rate for reclosing will be removed.
Subsections
16 and 17
6. Protection System Communications – For now the 99.99%
availability will remain a requirement within proposed New ISO
Rules Section 502.3 for new facilities. This requirement will be
re-evaluated when the AESO develops its proposed
Communication Rules.
Subsection
23
AltaLink supports with language suggestions.
AltaLink requests further clarity on why single pole trip
and reclose will become the standard practice for new
facilities. Single pole trip and reclose inherently adds
cost and complexity, and likely does not help the power
system in most cases. AltaLink recommends that the
wording be adjusted to make three pole trip and reclose
the standard practice for new facilities and define
exceptions to this in functional specifications.
AltaLink supports this ISO requirement and has no
comment
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7. Three Terminal Lines – Specific requirements will be provided
regarding the protection of new three (3) terminal lines.
Subsection
24
AltaLink supports with language suggestions.
AltaLink recommends that a statement be added to
subsection 24(1) requirement should be adjusted to
reflect, “No three (3) or more terminal lines shall be
allowed unless agreed to by the AESO and TFO’s.”
AltaLink recommends subsection 24(2) specify the
acceptable level of mis-coordination?
8. 500kV Protection System Setting Verification – Real time digital
simulation will be required for all new 500kV protection systems.
Subsection
28
AltaLink supports this ISO requirement and has no
comment
9. Transformer Protection – All new 25MVA and larger transformers
will require redundant transformer differential protection.
Subsection
29
AltaLink supports this ISO requirement and has no
comment
10. Bus Protection – New 144kV and lower voltage busses will
require redundant differential protection or studies to show
remote protections can provide adequate coverage.
Subsections
30 to 32
AltaLink supports with language suggestions.
AltaLink recommends further clarity be added in section
9.2 of ID#2012-004R which states “Slower clearing
times than those specified in section 502.3 subsection 8
are acceptable.” Subsection 8 of 502.3 specifies
protective relay operate times and not fault clearing
times.
11. Breaker Failure Protection – Based on extensive input from the
external technical workgroup clear requirements will be provided
that manage system reliability and where possible allow for the
lowest cost solutions.
Subsection
35
AltaLink supports with language suggestions.
AltaLink request further clarification if subsection 35(6)
applies to contact based breaker failure schemes such
as cooling system trips for Static Var Compensators
where longer breaker failure delay times are typically
used.
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AltaLink recommends that subsection 35(7) be revised
to state “For applications where free standing current
transformers are used with live-tank breakers, it is
acceptable to have a breaker fail operation for faults
located between the breaker and the current
transformer.”
12. Generating Unit Protection – Minimum protection requirements
will be provided such that system reliability is maintained. Any
protection requirements beyond this will be left up to the
discretion of the owner of the unit.
Proposed
Change
Subsections
37 to 45
Reference to the Subsections in Proposed New ISO Rules
Section 502.3
AltaLink has no comment
Stakeholder Comments and/or Alternate Proposal
AESO Replies
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(b) Subsections within Proposed New ISO Rules Section 502.3
In the AESO’s opinion, other than the key changes identified in (a) above, no other
substantive changes were made as the AESO redrafted and relocated
requirements from the AESO Protection Standard to proposed New ISO Rules
Section 502.3. As stakeholders review each subsection of New ISO Rules Section
502.3 please specifically comment on:
1) Are there any subsections where stakeholders feel that the language does not
clearly articulate the requirement either for the AESO or a market participant?
If yes, please indicate the subsection and suggest language that would more
clearly articulate the requirement.
AltaLink supports with language suggestions.
AltaLink recommends that subsection 6(a) be adjusted
to reflect the wording in section 15. AltaLink
recommends that the existing subsection be revised to
state “successfully detect all phase-to-ground faults with
ground impedance less than 5 Ohms, phase-to-phaseto-ground with ground impedance less than 5 Ohms,
phase-to-phase, and three (3) phase faults on the
protected equipment within the zone of protection;”
AltaLink recommends that subsection 11 be made
generic to indicate alarming on loss of potential. Other
equipment such as miniature circuit breakers may be
used instead of fuses on voltage circuits. AltaLink
recommends that the existing statement be revised to
the following: “A voltage transformer used for protective
purposes, including synchronism checking, must have a
loss of potential alarm.”
For Subsection 17(2):
AltaLink recommends further clarity be added to
subsection 17(2) to outline whether auto-reclosing is
permitted on hybrid lines (cables + overhead). AltaLink
also recommends that cables should be made more
generic by removing the word “underground” as not all
cables are installed underground.
AltaLink recommends that the phrase “capacitor bank
can” in subsection 33(3) be replaced with the word
“element”.
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2) Are there any subsections where stakeholders feel that the requirement does
not appropriately address system reliability concerns? Please provide an
alternate proposal if possible.
AltaLink supports this ISO requirement and has no
comment
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