Enhanced Round-Trip Process - WECC

March 9, 2021

Jamie Austin, PCDS Chair

2032 ADS PCM

Enhanced Round-TripProcess

Overview

2030 ADS Validation• Production Cost Model (PCM)• Power Flow Export Hours_ NorthernGrid

Addressing the Issue • Process• Committee Coordination• Software Solutions

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The 2030 ADS Dataset The ADS Package:

• 2030 Heavy Summer Power Flow Case • 2030 ADS Production Cost Model Case• 2030 ADS Round Trip Power Flow Case• Data Development and Validation Manual

The 2030 ADS has been produced through the efforts of many internal and external organizations:• WECC Committees: The Production Cost Data Subcommittees; The Production Cost Modeling

Subcommittee; The System Review Subcommittee; The WECC System Adequacy Planning staff; and The WECC System Stability Planning staff

• Participants from WECC Member Utilities• The Western Planning Regions• The National Labs: NREL, PNNL, LBNL• The California Energy Commission• Stakeholders at large, including Venders and Consultants

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ADS PCM Dataset

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ADS Dataset

ADS PCM

SRS - PF

“Reference Case”WECC L&R

ADS PF

PCDS - Other Data

ADS PCM\PF Validation

Posted Case

June 30, 2020

PCM Validation continues…Next official

posing: V2.0 ->

Mid-March

PF Export Hours Validated

by

NorthernGrid

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Use of the “Round-Trip” in NorthernGrid

To determine the more efficient or cost-effective transmission plan that would become the Study Plan, Northern Tier Transmission Group (NTTG) had utilized results from the production cost model to identify stressed hours; after review of the cases, data from eight of the export hours were subjected to reliability analysis using the power flow model.• The input and output data for these selected hours were transferred, using the round-trip

process, from the production cost model (i.e., GridView) to a power flow model (i.e., Power World) to perform the technical reliability analysis.

NorthernGrid is using the NTTG process for the 2020-2021 Study Cycle.

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Issue Discussion Resolution

Loads: 1. Starting with same time stamp L&R monthly Forecast2. BA level load forecast versus planning area forecast3. Small irrigation loads not reaching its potential

(summer pumping is scaled up, winter)

1. Confirming that loads submitted to NorthernGrid are the same as that submitted WECC L&R

2. BA Mapping issue

1. Require BA level data as stipulated in DPM

1. Bus mismatches present in the PCM case contribute to solution difficulty

1. Issue has to do with not having the right voltage angle when adding a new bus.

2. Power Flow uses “Angle Smoothing

1. In future, WECC staff will solve PF case when base case modifications are applied.

2. If just imported into GridView, Hitachi - ABB will look into "smoothing" angles.

1. Do NOT modify topology in PCM 1. Topology changes – read in epc file with PF changes Model consistent with PF1. Phase shifters2. Negative load3. Generators – voltage control, Pmax, Pmin,

Qmax, Qmin, technology

1. Initial changes to generators should be applied in power flow

1. DC line flow/direction 1. rectifier, inverter (alpha, gama) Already fixed I PCM

1. Checks for motor or battery representation (negative load check

2. Do not remove or set Pgen=zero for negative generation

3. Do not exceed Pmin or Pmax limits of generators

1. If motor loads, data needs to be identified in the L&R data collection. Checks:

2. Netted from load? Remove from load and model as a negative generation

1. Do not net out station service load for generation2. Doing this is causing Pgen to exceed Pmax it seems.

There is really no reason to modify the station service load.

1. Data Issue 2. Modify HR, using Pnet not Pgross

1. Data Issue 2. Modify HR, using Pnet not Pgross

1. Changes made in power flows after exporting the hourly data from PCM will definitely impact path flows.

1. Generator capacities greater than transformer or branch rating

Rules of thumb (all need to be checked with basic power flow)Do not exceed capacity of POI• 0 to 34.5 kV: 5 MW• 34.5 to 69 kV: 25 MW• 115 kV: 25 to 50 MW

1. Data issue in placing L&R generators that were not able to be aligned with the PF

The PCM Case Build Process Overview

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GridView Inputs

SRS Powerflow with L&R Resources“Reference Case”

WECC L&RLoad Forecasts

PDCS –Other DataHeat rates, solar and wind patterns, etc.

GridViewSRS Powerflow“Target Case”

GridView Outputs

Cases forPowerflowanalysis

Model for Production Cost analysis

Export

Load modeling Issue

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While all three are similar representations, information is lost in conversion.1. PF Base Case – Feeder Loads, DG, EE

all individually modeled as Load2. Internal PCM – DG/BTM converted to

generator models to capture their respective hourly shapes

3. PCM Export hour aggregates Load/DG, BTM, resulting in reduced bus load for the hour –

Vender is working on adding to PCM to model subsequent negative load independently; this is consistent with how it is modeled in the original power flow, however dispatches with varying hourly profiles.

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2

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Human input Error – BA mapping Checking PCM mapping vs. WECC base case

• The green dot indicates the sum of PCM loads • when mapping entered a WECC base case. • Loads that were not in the BA had been inadvertently

added to the BA in the PCM. • In the PCM, this larger group was being scaled

downward to match the BA forecast from the L&R• This resulted in too small loads in the PCM model

when observed at the bus level. Solution - - WECC will be sending out a

request for members to review BA mapping• This can help clean up base cases (BA in DPM but not

always populated

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DC Line Model NorthernGrid looked for a stressed S-N case for COI/PDCI PCM delivered! Spring during light load and high solar: COI at -3,321 (S-N) and PDCI -3,050 (S-N) This was the internal PCM model On export, COI at -7933 (S-N), PCI +2711 (N-S) WHAT HAPPENED!?

• PDCI DC Line model is uni-directional – PCM export code wasn’t ‘flipping’ DC direction in target PF caseIn addition …• PDCI limits 3220 N-S and 3100 S-N – but where’s the meter and what about losses?• In PCM, the metering was at Celilo – fine for the 3220 N-S rating, but the 3100 S-N is metered at Sylmar• S-N DC Losses needed to be accounted to assign limit at the Celilo terminal, less than 3100, or even 3050.• B-pole losses ~550 MW at this level of transfer in the model – limit transferred to Celilo ~2550 S-N

Short Term – add a DC pole model for each direction of flow in each WECC base case model – one would be turned ‘on’, the other ‘off’

Bus Mismatches

The export from PCM to a power flow case snapshot has some significant bus mismatches (worst in the example case was 4,762,977 MVA; 28 buses > 40,000 MVA mismatch) …

Issue has to do with not having the right voltage angle when adding a new bus.

Interim Solution - - WECC staff will solve PF case when base case modifications are applied. Power Flow uses “Angle Smoothing” … voltage and angle averages on adjacent busses.

Long Term Solution - - ABB will investigate a potential software solution.

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Topology changes include dispatch testFrom Number From Name To Number To Name Circuit % of Limit Used MVA or Amps?

366701 11C1472C1 366702 11C1472C2 1 852.3 Amps11337 BV_C1 11338 BV_STA 1 421.6 MVA11328 SOLAR_EV 11327 SOLAR_EC 1 380.4 MVA85677 MV1 85678 Inverter 1 236.8 MVA47296 HW_HILL_2 47297 HW_HILL_2 1 194.3 MVA23709 Q1170 23710 Q1170_BESS 1 192.1 MVA11336 BV_C2 11335 BV_PV1 1 187.4 MVA11336 BV_C2 11334 BV_PV2 1 187.4 MVA23707 Q1170_HV 23708 Q1170_MV 1 185.4 MVA23708 Q1170_MV 23709 Q1170 1 166.3 Amps32500 ULTR RCK 32402 ULTR-RCK 1 165.3 MVA85677 MV1 85679 Storage 1 158.5 MVA41286 ROZA 41284 ROZA M 1 151.6 MVA47436 COLW13B 47448 LVF23 1 142.9 Amps40756 ROZA 41284 ROZA M 1 142.2 MVA11110 NEWMAN 11229 NEWMN7G1 1 138.8 MVA36204 AERA_12 36090 AERA_ENG 1 133.2 MVA55087 DAISHOW8 55089 DAISHOW9 XR 133 Amps40911 SACJAWEA 41047 SUN_HARBOR+ 1 131.3 Amps57185 SCOTFCL2 58885 SCOT4_6 04 129.1 Amps11321 CANUT1_BAT 11320 BATTERY_W 1 125.9 MVA24786 CSA DIAB 24726 CSA DIAB 1 125.6 MVA34627 KETTLEMNSC1 34455 KETTLEMNS 1 125.3 MVA55185 SCOTFCL1 58785 SCOTF_4 02 123.4 Amps40843 PORT ANG 40841 PORT ANG 1 122 MVA23410 Q1434_MV2 23409 Q1434_MV1 1 120 Amps38365 N.HGN DM 33638 N.HOGAN 1 118.5 MVA37530 WHISKEYT 37531 WHISKEYF 1 115.8 MVA31101 SCOTIATP 31105 RIODLLTP 1 114.3 Amps54054 DOW GEN1 59061 DOW BUS2 66 113.6 Amps55450 IRRICAN2 54450 IRRICAN1 T1 112.4 MVA14045 PCC 85683 SUB_PSTR 1 111.9 MVA44931 HINKLE T 45233 HINKLE 1 111.8 Amps44931 HINKLE T 45139 HERMISTN 1 111.7 Amps21914 ORM1 21907 ORM12 2 110.2 MVA

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This is a sample PCM PF from NorthernGrid work. Occurrenceof these overloads leads to serious loss of faith in veracity of PCM case. The ADS process, if followed, would have preventedthis.

Yr(x-2)Posted ADS

PCM dataset

1a

Yr(x-2) Posted ADS

PF case1b

Yr(x-2)Posted Yr-10 HS PF

2a

Yr(x) Posted Yr-10 HS PF

2b

Yr(x) “L&R”

resource data3a

Yr(x) Posted ADS PF

7d

Yr(x) Posted ADS PCM

7e

Export PF and solve

6c

Initiate round trip by importing ADS Reference PF

into the Yr(x-2) ADS PCM4a

RAC Review7c

Stakeholder Review

7b

Post Yr(x) draft ADS PF and PCM to the

WECC website7a

Solve Yr(x) PF using data from 2f and all L&R

resources 3d

Place L&R “planned”

resources into the Yr(x) PF (2f)

3c

Compare resources in L&R

to resources in the Yr(x) PF (2f)

3b

Compare Yr(x-2) and Yr(x) PFs and export updated Yr(x) HS PF

2c

Update Yr(x) PF to be PCM “friendly”

2e

Resource mapping from Yr(x-2) ADS in

Yr(x) PF2f

Excel spread sheet resource comparisonof Yr(x) and Yr(x-2)

2d

ADS Reference PF for PCM import

3e

Yr(x)6ADS PF5d

PCD

S\SR

S\W

ECC

STA

FF

ADS Work Flow Enhancement Initiative – PCDS/SRS Proposal Yr(x) ver 1.2 3/3/2021Tasks 1 through 7 Development

ADS Reference Power Flow Case

Other Data

5a

Yr(x) “L&R”

load data5g

Incorporate the hourly loads from the L&R

data and validate5d

Incorporate other data into the Yr(x) PCM-1 dataset and

validate5b

Use Yr(x) forecast monthly loads from L&R data, and historic hourly

loads, to develop forecast Yr(x) hourly

loads.5h

Yr(x) PCM-1 dataset with

Yr(x) other data5c

Yr(x) PCM-2 dataset based on the ADS

Reference PF5f

Validate the updated Yr(x) PCM-2 dataset

6a

Yr(x) ADS PCM6b

SRS – Power Flow Reference Case

PCDS PCM Anchor Data Set

WECC PCM Staff

Add unit commitment data to newly mapped

resources in 3c.5e

5e

Yr(x) PCM-1 datasetTopology aligned with

Yr(x) PF & resources aligned with Yr(x) L&R

4b

Next Steps

Proposed approach would be to have PCDS and the SRS work together to improve the two models, PCM and Power Flow (PF)

Start with inventory model specific differences and outline needs Work with other RAC committees and WECC staff as necessary

(e.g., PCMS, StS, MVS, LRTF) to generate an implement solutions

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Contact:

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Jamie AustinJamie.austin@pacificorp.com