ABB Transmission Planning using Production Cost Simulation & Power Flow Analysis Jinxiang Zhu, Ph.D. Senior Principal, ABB Power Consulting ABB Group January 16, 2018 Slide 1
Power System Studies TECHNICAL STUDY OPERATION RELIABILITY ECONOMIC STUDY ECONOMIC OPERATION Power Flow Analysis System Impact Assessment Voltage & Transient Stability Reliability Compliance Reactive Compensation Study Retirement Study Path Rating study Congestion Revenue Right & LMP Forecasting Market Structure (EIM) Ancillary Services Public Policy (CPP, SB 350) Cost Benefit Analysis Renewable Integration Study LOLE Calculation Bidding Strategy
FERC ORDER 1000 FERC Order 1000 Mandated Regional and inter-regional transmission planning Identify transmission projects by public policy requirements, economic opportunities, and reliability needs Costs allocated roughly commensurate with estimated benefits Practical Perspectives Coordination of Inter-Regional transmission planning e.g. WECC, WestConnect, CAISO, NTTG, and ColumbiaGrid coordinated transmission planning Competitive solutions will be chosen multi-value project is preferred Common tool and common database to evaluate different projects - comparable Regional or Inter-Regional economic benefit definition agreeable Consistent between economic model with reliability model ABB Group January 16, 2018 Slide 3
Transmission Planning Goal: to identify efficient and cost-effective solutions to meet the transmission needs Transmission planning uses different tools Power flow study, using PSS/E, GE-PSLF, PowerWorld, etc. Economic transmission study, using GridView, PROMOD, etc. Not Well Coordinated Data Sources and Challenges Each tool may have different assumptions for future generation and transmission expansions Make the local area/region correct dispatch and topology is not enough Stitch and collaborate dispatch among multiple areas/regions may not be feasible, area/regional stressed case may have different assumptions and timing Due to non-coincident area/regional peaks and variable generation resources, it is difficult to predict generation dispatch and interchanges with neighboring systems Interchanges between areas and regions may have significant impacts on transmission planning results
Coordination in Transmission Planning Goal: to identify efficient and cost-effective solutions to meet the transmission needs Transmission planning uses different tools Power flow study, using PSS/E, GE-PSLF, PowerWorld, etc. Economic transmission study, using GridView, PROMOD, etc. Economic transmission study needs input from power flow case Topology, Impedance, Load distribution, Generator locations from power flow case Consistent assumption for generation and transmission expansion Power flow study needs economic dispatch from economic study results Generator dispatches, Bus loads, Estimated losses from economic dispatch System wide coincident loads and generation dispatch for variable resources and thermal plants based on security constrained economic dispatch to meet load and ancillary services Public policy (State RPS, Federal CPP, etc.) may change the way to operate system as of today; production cost model can provide the guidance on the dispatch changes.
Coordinated Transmission Planning with Economic Analysis Generation dispatch in power flow (PF) should be security constrained economic dispatch, just as how system operates Identify potential reliability concerns in PF as renewable energy penetration increase; such as, voltage support, ramping rates, inertia, frequency response, etc. Unit commitment determine voltage stability transfer limits, e.g. Central East in NYISO Example: Southern California MinGen issues Economic model cannot answer Technical study results may be affected by generation dispatch Contingency analysis in PF may identify additional constraints under contingency and normal conditions, which are not enforced in PCM Reliability Must Run (RMR) unit provide voltage supports in load pocket Economic analysis represent well power flow analysis Mimic market operation or utility operation closely (real power only) Losses are calculated closely as power flow analysis Production cost only enforces the selected limits; Power flow analysis requires all line/trans limits, VAR/voltage supports, inertia, and frequency response, etc.
Cost-Benefit Curve Minimizing annual production costs and transmission costs 13000 11000 Pa 9000 Cost 7000 5000 3000 Cb Pb Ca 1000 Economic Comparison of Cases A (with RMR) & B (w/o RMR) Annual Production Cost Cost S A V I N G S Ta=Pa + Ca A Ta - Tb = Net Benefit B Tb=Pb +Cb Total Cost 1 6 New Transmission 11 Projects 16 Annualized Capital Cost for New Transmission
Production Simulation and Transmission Analysis ABB Group January 16, 2018 Slide 8 https://www.misoenergy.org/library/repository/meeting%20material/stakeholder/ict%20materials/ict%20archi ve/minimizing%20bulk%20power%20costs%20study/20120605%20mbpc%20study%20report.pdf
WOTAB Region Analysis Projects New 230 kv from Rivrtrin Lewis Creek also add 345/230kV and 345/138kV Auto at Rivrtrin New 345 kv Rivrtrin Sub; Crockett Quarry/Rivrtrin Grimes 345 kv and add 100MVAr Cap Bank at Quarry New 500 kv from Lewis Creek Jacinto Cypress New 500 kv line from Hartburg to Sabine Cypress Upgrade Nelson 500/230 kv New 230 kv line from Richard to Nelson Hartburg Richard Nelson Addition of 2 (two) 500/230 kv transformers at Sabine Sabine New 500 kv Substation at Sabine New 230 kv line from Nelson to Sabine ALP South upgrade
WOTAB - 2022 Benefit/Cost Ratio 180.00 Cost-Benefit Analysis 160.00 140.00 MUSD 120.00 100.00 80.00 Annualized Transmission Cost 60.00 40.00 Production Cost Benefit 20.00 0.00 WOTAB_5A WOTAB_5B WOTAB_5B1 WOTAB_5B2b WOTAB_5B2c WOTAB_5B3 Case
Study Findings Benefit-to-cost ratios calculated for different load regions Benefit: Production cost savings Cost: Annualized cost of transmission additions In some regions, transmission costs outweighed benefits (RMR retained) In other regions, specific transmission projects pointed to savings in production costs Study identified cost-effective transmission projects that have potential to decrease overall production cost Additional studies (e.g. stability) were recommended to further study these projects
Round Trip Benefits Consistent model for reliability study (costs) and economic study (benefits) Generator dispatch in power flow case is based on security constrained economic dispatch well coordinated solution under different assumptions Multiple transmission solutions may fix the reliability issues under economic dispatch, however, each solution has different impacts on economic dispatch Allows re-dispatch resources due to transmission upgrade solution Topology changes allow more efficient generation dispatch (PCM) Power flow study under the most economic dispatch (PF) Identify the potential reliability issues under the economic dispatch (PF) Round trip verifies the solution effectiveness. (PF, DC Round trip allows consistent assumptions to calculate the benefits (PCM, AC Round trip minimize the gap between economic operation and reliability operation AC) DC) Transmission Planning Goal: Identify the efficient and cost-effective solutions to meet the transmission needs ABB Group January 16, 2018 Slide 12
Round Trip Challenges AC DC: Update Network data Bus and branch are easy updates PAR MW limits should not be updated Bus load data update Seasonal/TOU load distribution Negative loads Generator updates require extra efforts to make sure no duplication and no missing Many to One; One to Many DR, DG, EE, Pumping Load, B2B HVDC Tie Generators, etc. DC AC: Export Power Flow cases under different conditions It is easy to export a complete power flow case based selected hour load and generator dispatch Solving the exported power flow cases is not an easy task Data Problems For the gap generators, large generator is placed at low voltage bus with smaller transfer limit? Generator is placed behind a high impedance transformer Bus type (gen, load, slack); Shunts and Condensers; reference case ADS Goal is Fixing the Data Issues! ABB Group January 16, 2018 Slide 13
Round Trip Solutions? ABB built a system to automatically solve PSS/E cases in AC solution Python code to iteratively solve the case PSS/E OPF may be used to optimize the VAR supports Reference to a closer seasonal power flow case may enhance the solution possibility with a better starting point Not guarantee on AC solved using the process. ERCOT system testing showed 100% AC solution. WECC in PSS/E Develop a Similar Process in PSLF using EPCL? EPCL has limited library/tool, not as powerful as python PSLF solution engine is not as robust as PSS/E? Good News: We have a proven process in PSS/E as a reference GridView makes Round Trip possible and easy. Automatically Finding the AC Solution of Exported Power Flow Case is the KEY for Round Trip! ABB Group January 16, 2018 Slide 14
Contact Information Jinxiang (Jin) Zhu Senior Principal Consultant, ABB Inc. 940 Main Campus Drive, Suite 300 Raleigh, NC 27606 Email: jinxiang.zhu@us.abb.com Phone: (919) 807-8246 Fax: (919) 807-5060 ABB Group January 16, 2018 Slide 15
ABB Group January 16, 2018 Slide 16