Please be advised of the following notices: 1. Due to ongoing development discussions and engineering studies, the Transmission System Network Upgrades identified as part of Transmission Service Request #411 will not be included in the System Impact Study (SIS) Analysis for Generator Interconnection Procedures (GIP) Study Groups #32 to #35. GIP Study Group #32 to #35 analysis will be limited to the 2024 Transmission System configuration plus any material Network Upgrades identified in higher queued projects. 2. Due to the expected increase in inverter-based generation resources in Nova Scotia and the anticipated decrease in synchronous generation related to the requirement to phase-out of coal fired generation by 2030, GIP System Impact Study analyses are being expanded to include Electromagnetic Transient (EMT) Analysis in addition to Load Flow and Dynamic Analysis. To accommodate this change, Interconnection Customers are required to provide the System Operator with the appropriate PSCADTM models for their generators in addition to the PSS®E generator models required in the Generator Interconnection Procedures. A separate report will be issued for the Electromagnetic Transient Analysis. 3. Notice Date: May 08, 2024 To be eligible for inclusion in the Interconnection System Impact Study stage, and thereby advance the Interconnection Request’s initial Queue Position, the Interconnection Customer must meet the progression milestone requirements of Section 7.2 of the GIP at least ten (10) Business Days prior to the Interconnection System Impact Study commencement date. For clarity, item 7.2 (i) – provision of a detailed stability model for the generator(s) shall mean: - Provision of PSSE and PSCAD models in compliance with documents NSPI-TPR-015-2: PSSE and PSCAD Model Requirements, and
- Provision of test data demonstrating model testing in compliance with NERC, NPCC and NSPI criteria. NSPI-TPR-014-1: Model Quality Testing lists the minimum requirements that will be performed by NSPI. Additional testing may be performed to assess compliance with all applicable criteria. Any test not meeting the minimum NSPI requirements will be documented in the MQT report to the IC.
NSPI-TPR-015-2: PSSE and PSCAD Model Requirements and NSPI-TPR-014-1: Model Quality Testing will undergo revision as the grid evolves and performance criteria changes. The most up to date version will be provided as they become available. 4. Notice Date: June 24, 2024 7.6.7. Inertia Response - WECS
WECS Generating Facilities shall provide inertia response equivalent to a Synchronous Generator with a synchronous condenser, with rated MVA as a percentage of the rated MW of the associated WECS. The scaling factor is dependent on POI voltage. Support can be from a device other than a synchronous condenser if equivalent SCMVA support can be demonstrated. Facilities adjacent to existing IBR facilities that do not have additional inertia support or in extremely weak areas of the grid may require greater inertial support and/or have turbines with a very low SCR requirement for ride through. The SIS will determine the total inertial response required to meet performance requirements. WECS turbines shall support over frequency deviations with a power boost (virtual inertia response) for at least 10 seconds and, where headroom exists, shall offer over-frequency and under-frequency control with a deadband of +/- 0.2 Hz and a droop characteristic of 4%. The following table is in effect starting from SIS Round 27: Inertia Response - WECS Scaling factor |
---|
POI voltage | SIR scaling factor | 69 kV | 0.60 | 138 kV | 0.60 | 230 kV | 0.52 | 345 kV | 0.48 |
Example: 100MW WECS with 138kV POI will require, at a minimum, a synchronous condenser with an MVA rating of at least 60 MVA.
5. Notice Date: September 18, 2024 Study Group 39 was added to the GIP Study Calendar in response to the anticipated timing of the provincial Green Choice Program procurement. Schedules for Study Groups 38 and 40 (previously numbered 39, May 2025) were not affected. Projects entering SIS Group 39 which are not electrically remote from projects in SIS Group 38 will require the associated Group 38 studies to be progressed sufficiently before they can commence. *End of Notice* |