Jie Wan, Alstom Grid

Casey Cathey, SPP

23 June 2014

Reserve Requirement Calculator in SPP Integrated Market Place

SPP Integrated Marketplace Project

• SPP Integrate Marketplace implemented March 1, 2014

• Market application components

−Day-Ahead Market, Reliability Unit Commitment process, Real-Time Balancing Market

−Security Constrained Unit Commitment (SCUC) and Security Constrained Economic Dispatch (SCED)

© ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied on that it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided without liability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

Presentation title - 03/07/2014 – P 22

Security Constrained Economic Dispatch (SCED)

− Co-optimization of 5 products: Energy, Regulation-Up, Regulation-Down, Spinning, and Supplemental

−Hourly zonal contingency reserve (CR) minimum requirement and maximum requirement are calculated in a daily basis by Reserve Requirement Calculator(RRC)

RRC Business Process Timeline

Two Day Ahead

12:00AM - 12:00 AMDay Ahead

12:00AM - 12:00 AM

Paericipant submit

external supply decision

5:00PM

SPP calculates and posts RZ

Min/Max Requirements

7:00AM

11:00AM

DA market closes

4:00PM

DA results Posted

© ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied on that it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided without liability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

Presentation title - 03/07/2014 – P 3

Hour 2000

2-Day Ahead

DBDA-RUC

Solution Done

Hour 0700

Day Ahead

RRC Solution

Done

RRCe

performs RRC

Hour 1100

Day Ahead

DAMKT bidding

closes & Clearing

Starts

Hour 2000

Day Ahead

DA-RUC

Solution Done

Participants

MOIMDB

RRC Overview

Oracle

Market

Day-Before

Day-Ahead RUC

(DBDA-RUC)

Approved

Reserve Rqrmts

Reserve Obligations

Participants

Historic

responding

units & dist

factors

Dispatch & LF

by hour for OD

Reserve

Requirements

Calculator

Overview

interface

interface

External

Reserve Zone

Obligation

Transfer

Schedules

interface

MOI

Actions:

Set up case: associate w/ MD-RUC

Study

Initiate Min/Max Calc Run –

All, RZ, or RZ/hour

Select or Ignore Binding Constraint

Review results

Approve / Publish Results

© ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied on that it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided without liability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

Presentation title - 03/07/2014 – P 4

Market

Database

CSV

CSV

STNET Clone

NETMOM

DB

Reserve Zone

Min/Max Calculator

RZ Min & Max

limits

Notes

Hourly injections into the Calculator come from DBDA-

RUC study.

Currently: 4 Reserve zones, 593 units, 356 units which

qualify for reserve sharing.

Requirements by product requires additional hourly load

and renewables forecast inputs.

Iterative and interactive interaction with Calculator will be

via MOI.

Contingency reserve power transfer results need to be

presented in MOI with

sort / filter options by zone, unit, hour, violation %, etc.

Will also calculate contingency reserve requirement, per

RZ.

RRC Features

• Provides

−Hourly minimum zonal CR requirements−Hourly maximum zonal CR limits;−The list and loading levels of the transmission

constraints/branches which determine the zonal requirements/limits

−Asset owner reserve obligation

© ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied on that it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided without liability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

Presentation title - 03/07/2014 – P 55

• Used a DC power flow and sensitivity based-method

• Integrated with Market Clearing Engine(MCE) for data and system modeling consistency between RRC and MCE.

Minimum CR Requirement and Maximum CR limit

• Zonal minimum CR requirement is defined as the minimum reserve capacity that must be available within a given reserve zone (due to transmission transfer limitations) in order to be able to survive the loss of the largest unit within the zone while also maintaining reliable operation of the power system.

• Zonal maximum CR limit is defined as the maximum

© ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied on that it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided without liability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

Presentation title - 03/07/2014 – P 66

• Zonal maximum CR limit is defined as the maximum MWs that the reserve zone could supply to the rest of the network (due to transmission transfer limitations) in the event of the most constrained CR event outside of the reserve zone.

RRC Modeling

• Resource Modeling

−Use resource commitment/dispatch, phase-shifter setting and transactions from DBDA RUC solution

−Use real time offers including capacity limits, commit status/outage status, ramp rate Limit, reserve qualification and dispatch status

© ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied on that it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided without liability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

Presentation title - 03/07/2014 – P 77

and dispatch status

−Treat Jointly-Own Units (JOU) /Plant units/combined Cycle units modeled as a whole in a lost-of-generation event

−Use resource historical reserve sharing capability to indicate whether a resource is capable of providing CR response to a loss-of-generation event

RRC Modeling

• Transmission network modeling

−Transmission outage schedules for each hour of the Operating Day(OD)

−User configurable network branches, generic transmission security constraints represented with aggregate and proxy PTDF flowgates

© ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied on that it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided without liability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

Presentation title - 03/07/2014 – P 88

PTDF flowgates

−Constraint limits used in RRC evaluation consider transmission capability set aside to protect against instability, uncontrolled separation, or cascading outages where needed

−Linear DC power flow model and sensitivity based generic transmission constraint model

RRC Modeling

• Load and Loss Modeling

−Hourly mid-term load forecast by load forecast zone are allocated to the energized electrical nodes based on hourly load distribution factors.

−No Marginal loss model is in the RRC since load forecast include loss

© ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied on that it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided without liability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

Presentation title - 03/07/2014 – P 99

include loss

• Contingency Event Modeling/Assumption

−Simulates loss-of-generation event

−Calculates the system base power flow based on Mw output from DBDA RUC

−Resource commitment and dispatch carried from the DBDA RUC solution to the RRC is already a secure solution taking into account the likely contingencies.

Methodology

• Calculate the base power flow using DBDA RUC commitment and dispatch

• Evaluate each loss-of-generation

−Re-balance the lost generation Mw among available contingency reserve sharing resources

−Calculate the incremental power flow−Calculate the PTDF based the power flow difference

© ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied on that it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided without liability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

Presentation title - 03/07/2014 – P 1010

−Calculate the PTDF based the power flow difference−Evaluate maximum transferable contingency reserve

capacity

• Determine the minimum CR requirement and maximum CR limit for each zone based on the PTDF over all constraints/branches and loss-of-generation events.

Incremental Power Flow for Loss-of-Generation Events

• Incremental Power Flow for Min CR Requirement− the lost mw in a reserve zone is re-balanced by the reserve

sharing capable resources outside the reserve zone in proportion to their CR sharing MW-capabilities

• Incremental Power Flow for Max CR Limit− the lost generation of a contingency resource outside a reserve

zone is re-balanced by the reserve sharing capable resources inside the reserve zone in proportion to their CR sharing MW-

© ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied on that it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided without liability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

Presentation title - 03/07/2014 – P 1111

inside the reserve zone in proportion to their CR sharing MW-capabilities.

• Resource CR Sharing Capacity:−Operating reserve qualification−DBDA RUC dispatch −Capacity limits −Offline supplement Maximum limit−Ramp rate limits−Contingency reserve response time

PTDF and Maximum Import/Export MW Calculation

• PTDF is defined as the sensitivity of the flow on a transmission constraint/branch with respect to the loss-of-generation event and the corresponding allocation of the lost generation among the reserve sharing resources.

• Hourly PTDFs for min CR requirements and max CR limits are calculated over

© ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied on that it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided without liability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

Presentation title - 03/07/2014 – P 1212

− transmission constraints/branches− reserve zones− loss-of-generation events

• The maximum deliverable import/export Mw is computed based on the remaining amount of the transmission transfer capability and PTDFs

Min CR requirement and Max CR limits Calculation

• The minimum CR requirement for a reserve zone is the maximum of the differences between the lost MW in a loss-of-generation event and the maximum deliverable import Mw that can be carried into the reserve zone without exceeding the remaining amount of the transmission transfer capability of a constraint over all transmission constraints, branches and all loss-of-generation candidates

© ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied on that it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided without liability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

Presentation title - 03/07/2014 – P 1313

• The maximum CR for a reserve zone is the minimum of the maximum deliverable export Mw from the zone in a loss-of-generation event outside the reserve zone e over all transmission constraints/branches and all loss-of-generation candidates.

SPP Production Results

# of Units 593

# of Buses 15710

# of Branches 20727

# of Reserve zones 4

# of loss-of-gen events 10

# of Constraints 5

ReserveZone MinCRReq MaxCRReq

1 308.76

© ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied on that it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided without liability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

Presentation title - 03/07/2014 – P 1414

• Solution time:

−About 6 minutes per hour−with 4 hour being executed in parallel−About 50 minutes for 24 hours

1 308.76

2

3

4 493.425

Challenges

• Use pre-selected transmission constraints instead of full branch evaluation

−Need better constraint management and study

• Dependency with DBDA RUC results

−Need good coordination between DBDA RUC, RRC and DA and RUC study

• Not accurate for RTBM study due to the changes of the

© ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied on that it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided without liability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

Presentation title - 03/07/2014 – P 1515

• Not accurate for RTBM study due to the changes of the system condition and constraint enforcement

• Will consider the impact of possible reserve deployment in transmission constraint evaluation in DA , RUC and RTBM in the future

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