1. Chair: Siri Varadan, Nexant, Inc. Panelists: Elham Makram, Clemson University Thomas Baldwin, Florida State University Mark McGranaghan, Electrotec Concepts PANEL DISCUSSION P5 Impact of Distributed Generation on Harmonics and Power Quality Chair: Siri Varadan, Nexant, Inc. Panelists: Elham Makram, Clemson University Thomas Baldwin, Florida State University Mark McGranaghan, Electrotec Concepts

2. DG Conference, Clemson, SC March 13-15, 2002 2 Presentation Topics and Order Effect of Harmonics on Distributed Generation – Effect of Harmonics on Distributed Generation – –Elham Makram Harmonic and Distributed Generation Interaction Issues in the U.S. Navy All-Electric Ship Program – Harmonic and Distributed Generation Interaction Issues in the U.S. Navy All-Electric Ship Program – –Tom Baldwin PQ Issues for DG Applications – PQ Issues for DG Applications – –Mark Mc Granahan Software Aspects of PQ in a DG Context – Software Aspects of PQ in a DG Context – –Siri Varadan General Discussion General Discussion

3. DG Conference, Clemson, SC March 13-15, 2002 3

4. ‘Independent’ Modules to Ensure Vendor-Independence in Utility- wide PQ Monitoring Systems by Mehmet Kemal Celik

5. DG Conference, Clemson, SC March 13-15, 2002 5 Overview of the Presentation Introduction Introduction Modular System Design Modular System Design Benefits Benefits Functional Design Functional Design A Customized Analysis Example A Customized Analysis Example Conclusions Conclusions

6. DG Conference, Clemson, SC March 13-15, 2002 6 Power Quality Monitoring Systems Integrated systems of several PQ monitors are being set up Integrated systems of several PQ monitors are being set up –increasing number of monitors –emerging computer technologies on hardware and software area –different architectures that serve all PQ monitors with a single large database »client-server »Intranet/Internet

7. DG Conference, Clemson, SC March 13-15, 2002 7 Power Quality Monitoring Systems Such integrated designs have several advantages Such integrated designs have several advantages –efficient and fast analysis of large volumes of data –establish centralized PQ data –usage of standard PQ indices within the utility –standardization of customer complaint evaluation –modular, expendable and portable system design –reduction in system maintenance and expansion costs –standard data analysis tools on LAN/WAN, Intranet, etc. –centralized security system

8. DG Conference, Clemson, SC March 13-15, 2002 8 Main PQ Monitoring System Components Communication System - physical media (fibre optics, copper, wireless, etc), modems (DSL, telephone, etc.), Ethernet network components (switches, routers, etc), etc. Communication System - physical media (fibre optics, copper, wireless, etc), modems (DSL, telephone, etc.), Ethernet network components (switches, routers, etc), etc. Information Technology (IT) System - computers (data servers, polling stations, client stations, etc), system software (operating system, etc), database system, protocol converters, user applications (GUI, analytical applications, alarm and information dispersal software, web publishing, etc.), etc. Information Technology (IT) System - computers (data servers, polling stations, client stations, etc), system software (operating system, etc), database system, protocol converters, user applications (GUI, analytical applications, alarm and information dispersal software, web publishing, etc.), etc. Monitoring System - instrumentation (PQ monitors, RTUs, sensors, etc), data retrieval and configuration software, etc Monitoring System - instrumentation (PQ monitors, RTUs, sensors, etc), data retrieval and configuration software, etc

9. DG Conference, Clemson, SC March 13-15, 2002 9 PQ Monitoring System Components Monitoring system WAN Polling server ODBC database Database/Application server Communication system IT system End users PQ Monitors

10. DG Conference, Clemson, SC March 13-15, 2002 10 Implementation Benefits Removes vendor dependencies - The best alternatives, specific to meet all of the utility’s requirements, are used Removes vendor dependencies - The best alternatives, specific to meet all of the utility’s requirements, are used Easy implementation of analysis applications Easy implementation of analysis applications –Analytical applications can be written that use the ‘standardized databases –Industry standard and vendor independent applications, each best suited to meet utility’s requirements Ease in implementation of web reporting applications - Latest web hosting and interactive site technologies can be used. Ease in implementation of web reporting applications - Latest web hosting and interactive site technologies can be used. Economic benefits - With several alternative systems, price of the individual modules is more competitive Economic benefits - With several alternative systems, price of the individual modules is more competitive

11. DG Conference, Clemson, SC March 13-15, 2002 11 Operational Benefits Maintenance of a standard database Maintenance of a standard database –Allows cheap and regular maintenance. Facilitates easy database expansion. Single database ensures that there is no duplication of data from all current and potential future power quality monitors. Existing trained personnel can quickly come up to speed with the operation & maintenance of the system - No new elaborate training is necessary Existing trained personnel can quickly come up to speed with the operation & maintenance of the system - No new elaborate training is necessary

12. DG Conference, Clemson, SC March 13-15, 2002 12 Future Expansion Benefits Future subsystem components can be selected solely on their merit - ‘Vendor- independence’ Future subsystem components can be selected solely on their merit - ‘Vendor- independence’ Modular design allows Modular design allows –utilization of future advances in instrumentation, communication, and software technologies –utilization of upgrading without a major investment in a complete system overhaul

13. DG Conference, Clemson, SC March 13-15, 2002 13 Conceptual Design Future expandability; plug-and-play concept Database Leased Lines or other media Fiber Optics and DSL modems Instrumentation Database server Meter server LAN End user Required software - Communication - Data logging - Configuration Current PQ metersFuture PQ meters

14. DG Conference, Clemson, SC March 13-15, 2002 14 Functional Design

15. DG Conference, Clemson, SC March 13-15, 2002 15 Software Modules Data from Communication server ODBC database Application server 3  component analysis ‘Basic’ software is installed on the Communication server Harmonic analysis Web reporting Event reporting PQ characterization Independent software modules, each of which can be modified/upgraded independently Import/Export of data to other formats (PQDIF,COMTRADE, etc)

16. DG Conference, Clemson, SC March 13-15, 2002 16 Data Flow

17. DG Conference, Clemson, SC March 13-15, 2002 17 Data Analysis and Reporting

18. DG Conference, Clemson, SC March 13-15, 2002 18 Data Analysis and Reporting Calculation Modules Calculation Modules –RMS, Root Mean Square, (voltage or current) –SARFI –Fundamental voltages and currents of Fourier series –Total voltage harmonic RMS, etc. Expert system rules constitute a simple if-and-then logic for combining windowed time data with relational and topological data Expert system rules constitute a simple if-and-then logic for combining windowed time data with relational and topological data Extract module basically extracts the required portion of the data from database tables Extract module basically extracts the required portion of the data from database tables Display is in the form of graphs, tables and text Display is in the form of graphs, tables and text

19. DG Conference, Clemson, SC March 13-15, 2002 19 Typical Customization – Disturbance Aggregation Monitors track individual PQ disturbances Monitors track individual PQ disturbances A deviation on a single phase at a single instant in time will be recorded as a disturbance A deviation on a single phase at a single instant in time will be recorded as a disturbance An electrical system event may cause multiple disturbances An electrical system event may cause multiple disturbances For example, a single event: a tree branch blowing against a 12kV line For example, a single event: a tree branch blowing against a 12kV line –It can result in voltage sags on more than one phase –Sags will be recorded at PQ monitors located at different parts of feeder with small time lags –Arcing may generate wave shape faults as well –Furthermore, fault current may result in a series of momentary outages, maybe followed by an interruption to service PQ monitoring should be able to relate all disturbances to the actual cause (event) PQ monitoring should be able to relate all disturbances to the actual cause (event)

20. DG Conference, Clemson, SC March 13-15, 2002 20 Event Reporting (Disturbance Aggregation)

21. DG Conference, Clemson, SC March 13-15, 2002 21 Disturbance Aggregation Two sets of disturbances, one on feeder 1, and another on feeder 2 Two sets of disturbances, one on feeder 1, and another on feeder 2 –voltage sag at t = 1 from PQ monitor 2 on feeder 1 –Voltage sag from PQ monitor 1 at t = 2 on feeder 1 –Voltage sag from PQ monitor 3 at t = 2.5 on feeder 1 –Momentary outage from PQ monitor 2 at t = 3.5 on feeder 1 –Voltage sag from PQ monitor 4 at t = 3.6 on feeder 2 –Voltage sag from PQ monitor 5 at t = 4 on feeder 2 –Waveform distortion from PQ monitor 6 at t = 4.5 on feeder 2

22. DG Conference, Clemson, SC March 13-15, 2002 22 Disturbance Aggregation Sequence of disturbances Sequence of disturbances –all due to a tree branch blowing against a line on feeder 1 –Or, the disturbances on feeder 2 may be due to an independent event on feeder 2, such as lightning

23. DG Conference, Clemson, SC March 13-15, 2002 23 Disturbance Aggregation A properly sized moving time window that starts with the first event of the sequence will capture most of the practical situations, such as event data that are from different phases on the same monitor that are far apart from each other only by infinitesimal time intervals, etc.

24. DG Conference, Clemson, SC March 13-15, 2002 24 Disturbance Aggregation However, fixed size moving time windowing may cause inaccurate aggregation of events if it is not properly sized and used as the only decision criteria

25. DG Conference, Clemson, SC March 13-15, 2002 25 Disturbance Aggregation If relational information is used with adaptive window sizing, accuracy and robustness is enhanced

26. DG Conference, Clemson, SC March 13-15, 2002 26 Disturbance Aggregation In actual implementation, many more variables are considered, such as severity of the events sequence with respect to the location relational information and connectivity electrical and geographical distance types of substation and feeder equipment used protection schemes utilized, etc.

27. DG Conference, Clemson, SC March 13-15, 2002 27 Conclusions Modular – system components can be changed without major modifications Modular – system components can be changed without major modifications Expandable – new monitoring systems can be added without a complete system overhaul Expandable – new monitoring systems can be added without a complete system overhaul Easier to maintain Easier to maintain Standard unified set of tools across the users Standard unified set of tools across the users Customizable applications Customizable applications