Dear PGDTF members,
Just let you know that we have posted the first GIC model (GIC input file and associate PSSE base case) in ERCOT MIS website on 09/26/2017. You can click on the link
https://mis.ercot.com/pps/tibco/mis
to go to ERCOT MIS system, then click on “Transmission Service Provider Information” to find out “GIC System Models”:
Notes for the first draft GIC model
1.
The GIC model (GIC input file) has been developed based on the PSSE base case 16SSWG_2021_SUM1_U1_Final_GIC09122017.raw, which is almost the same as the PSSE base case
16SSWG_2021_SUM1_U1_Final_10152016.raw (PGDTF recommended) and with a minor modification that Bus 7041 has been changed to Bus 170174. The reason is that ERCOT EMS system and late SSWG future base cases have made the same change.
2.
For the substations that neither TSPs nor REs have provided related data (longitude, latitude, grounding resistance, and earth model), ERCOT queries out the longitude
and latitude values from MACOMB Map of CIM Model, uses 0.1Ù as default grounding resistance value, and keeps blank
for the earth model.
3.
In the end of August, 2017, ERCOT has sent requests to six TSPs, asking them to correct substation number duplicate issue. Since one TSP has not yet corrected the duplicate
issue, ERCOT has temporarily assigned substation numbers in that TSP substation number range in order to develop the first GIC model on time. However, we really need the TSP to correct this issue by themselves in following GIC model development.
4.
In this GIC model, ERCOT uses default data from the PSSE base case to complete the transformer table, branch table, and fixed shunt table, since these data from both
TSPs and REs are incomplete and have errors. ERCOT will integrate TSP and REs’ data into these tables in the following passes.
5.
When developing the first GIC model, ERCOT has found that two side buses for some 2-winding transformers and three side buses for some 3-winding transformers are not
in the same substations, which causes GIC calculation interruption. ERCOT has temporarily resolved this issue through manually assigning the two side buses of a 2-winding transformer or three side buses of a 3-winding transformer with the same station. ERCOT
will send out a request later asking TSPs to correct this issue for their own transformers.
Please let ERCOT know if you have any questions.
Thanks.
Qiuli
Qiuli Yu
Network Model Engineer, Sr.
Electric Reliability Council of Texas, Inc.
2705 West Lake Dr.
Taylor, TX 76574
Phone: 512-248-4161