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DUIT: Distributed Utility Integration Test August 2003 • NREL/SR-560-34389 DUIT: Distributed Utility Integration Test Distributed Utility Associates Livermore, California National Renewable Energy Laboratory 1617 Cole Boulevard Golden, Colorado 80401-3393 NREL is a U.S. Department of Energy Laboratory Operated by Midwest Research Institute • Battelle • Bechtel Contract No. DE-AC36-99-GO10337 August 2003 • NREL/SR-560-34389 DUIT: Distributed Utility Integration Test Distributed Utility Associates Livermore, California NREL Technical Monitor: Ben Kroposki Prepared under Subcontract No. AAD-0-30605-05 National Renewable Energy Laboratory 1617 Cole Boulevard Golden, Colorado 80401-3393 NREL is a U.S. Department of Energy Laboratory Operated by Midwest Research Institute • Battelle • Bechtel Contract No. DE-AC36-99-GO10337 NOTICE This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States government or any agency thereof. Available electronically at http://www.osti.gov/bridge Available for a processing fee to U.S. Department of Energy and its contractors, in paper, from: U.S. Department of Energy Office of Scientific and Technical Information P.O. Box 62 Oak Ridge, TN 37831-0062 phone: 865.576.8401 fax: 865.576.5728 email: [email protected] Available for sale to the public, in paper, from: U.S. Department of Commerce National Technical Information Service 5285 Port Royal Road Springfield, VA 22161 phone: 800.553.6847 fax: 703.605.6900 email: [email protected] online ordering: http://www.ntis.gov/ordering.htm Printed on paper containing at least 50% wastepaper, including 20% postconsumer waste Acronyms AEP............................American Electric Power ATE............................automated test environment CHP............................combined heat and power CTs.............................current transformers, combustion turbines DAS............................data acquisition system DER............................distributed energy resources DG..............................distributed generation DR..............................distributed resources DOE ...........................US Department of Energy DUIT..........................Distributed Utility Integration Test EMF ...........................electromagnetic fields EMI ............................electromagnetic interference EPRI...........................Electric Power Research Institute EPS.............................electric power system FACTS .......................Flexible AC Transmission Systems GENCOs ....................generation companies IEC .............................International Electrotechnical Council IEEE...........................Institute of Electrical and Electronics Engineers ISO .............................independent system operator LHV ...........................lower heating value MCFC ........................molten carbonate fuel cell MGTF ........................Modular Generation Test Facility NDZ ...........................non-detect zone NEMA........................National Electrical Manufacturers Association NREL .........................National Renewable Energy Laboratory ORNL.........................Oak Ridge National Laboratory PAFC..........................phosphoric acid fuel cell PCC............................point of common coupling PEAC .........................Power Electronics Applications Center PEMFC ......................proton exchange membrane fuel cell PG&E.........................Pacific Gas and Electric Co. PQ ..............................power quality PTs .............................potential transformers PV ..............................photovoltaics RAMD........................reliability, availability, maintainability, and durability RTOs..........................regional transmission organization SCADA......................Supervisory Control and Data Acquisition SCCR .........................Short Circuit Contribution Ratio SMES .........................superconducting magnetic energy storage SOFC..........................solid oxide fuel cell iii TES ............................Technical and Ecological Services THD ...........................total harmonic distortion T&D ...........................transmission and distribution, transmission and distribution utility TRANSCOs ...............transmitting utilities UCI.............................University of California at Irvine UL ..............................Underwriters Laboratories VOS............................value of service iv Table of Contents Table of Figures............................................................................................................................vii Table of Tables.............................................................................................................................viii 1 Needs Assessment and Testing ......................................................................................1 1.1 Introduction and Overall Project Description..........................................................1 1.2 Scope, Objectives, and Goals...................................................................................5 1.3 Technology Selection and Evaluation .....................................................................8 1.4 Site Evaluation and Selection ................................................................................11 1.5 Electrical and Operational Issues...........................................................................12 1.6 DUIT's Potential Results and Policy Implications.................................................15 2 Assessment of Test Sites...............................................................................................18 2.1 Introduction............................................................................................................18 2.2 Site Analysis Methodology....................................................................................18 2.3 Assessment of Sites................................................................................................23 2.4 Analysis..................................................................................................................58 2.5 Conclusions and Recommendations ......................................................................59 3 Technology Report..........................................................................................................61 3.1 Introduction: Selection and Evaluation of Technologies for the DUIT.................61 3.2 Electric Conversion and Grid Interface .................................................................63 3.3 Inverters and Inverter-Based Technologies ...........................................................68 3.4 Engine Technologies..............................................................................................83 4 Test Protocols..................................................................................................................88 4.1 Introduction............................................................................................................88 4.2 Unintentional Islanding Tests................................................................................89 4.3 Voltage Regulator Tests.......................................................................................112 4.4 Reclosing Tests ....................................................................................................118 4.5 Sectionalizing Devices Tests...............................................................................121 4.6 Synchronization Tests..........................................................................................128 4.7 Fuse Coordination Tests ......................................................................................131 4.8 Capacitor Switching and Operation.....................................................................134 4.9 Short Circuit Tests ...............................................................................................135 4.10 Distribution System Stability Tests .....................................................................140 4.11 Cold Load Pickup Tests.......................................................................................147 4.12 Faults on Adjacent Feeders Tests ........................................................................147 4.13 Network Secondary Tests ....................................................................................147 4.14 Substation Backfeed Tests...................................................................................148 4.15 Prioritization ........................................................................................................149 v 5 Project Plan....................................................................................................................150
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