Using Synchrophasor Data to Diagnose Equipment Mis-operations and Health Alison Silverstein WECC JSIS Meeting, September 10,

Background and thesis of paper Background of paper Pulling this together under contract to DOE SGIG program, to extract insights from the SGIG-SGDP synchrophasor projects Process – review examples and stray mentions from NASPI presentations and conversations, find company experts to provide additional detail Thesis of paper Operating engineers are using synxr data to identify and diagnose a wide number of generation and transmission events. This off-line use is producing tremendous value in terms of potential equipment damage avoided and potential outages averted. By documenting the examples and the diagnostic and deductive processes used for each case, the entire industry can learn quickly and implement this great synxr value source 2

Mis-operations examples 1) Generator settings and generator equipment failures Cumberland nuke PSS setting (TVA) Malfunctioning generator PSS (NYISO) Redbud powerplant oscillations (OG&E) Malfunctioning generator AVR control system (NYISO) Voltage oscillations at nuclear plant (Dominion) Faulty generator control card (ERCOT) Protecting power system stabilizers (Manitoba Hydro) Colstrip control unit malfunction (EPG) Governor control malfunction in Alberta caused large power oscillations on California-Oregon lines (CAISO) 3

Mis-operations examples 2) Wind plants and oscillations Wind plant oscillations (OG&E) Wind controller software update flawed (ERCOT) Wind events and turbine controllers (ERCOT) 4

Mis-operations examples 3)Transmission equipment Failing potential transformer (ATC) Finding loose connections in potential circuits at fuses and terminal blocks (OG&E) Voltage transformer failing (Dominion) Identifying 69 kV arrester failure affecting customers (ATC) Voltage pull-downs linked to line communications carrier (OG&E) PQ monitoring (OG&E) Transmission-level fault analysis (NYISO) 5

Mis-operations examples 4)Proactive uses of PMUs for equipment installation and protection Monitoring system current imbalance to protect large power generator rotors (Dominion) Using PMUs to install and calibrate equipment (Dominion) 6

What happens next? Still collecting examples, writing paper, and fact-checking Paper to be released in October at CIGRE and NASPI mtgs Start outreach campaign at NERC, NATF, NAGF, JSIS, and more Would like to build a library of synxr data for these examples, that analysts can examine to look for event signatures for automated diagnosis – have asked WECC if we can use the formats and structure for their automated grid disturbance library to set up a separate data library for these small events (potentially hosted at PNNL) Look at OG&E automated event reports to see if these are share-able 7

Got good examples to add to the list? Please let me know asap, and be prepared to provide high- quality synxr data images and spend two 30 minute sessions on the phone with me to explain the event and then answer additional questions. Thanks!