Dynamics of Disturbances ILAs

 

ILA #1

Using actual frequency related disturbance events, describe & illustrate how frequency control process accomplished in NERC power systems

1.     Explain theory of frequency control including explanation of load frequency relationship, explanation of role of inertia, description of governor operation, description of usage of constant frequency, constant interchange & tie-line bias modes of AGC, description of types of operating reserves, description of CPS1 & BAAL, description of DCS, description of purpose, design & operation of UFLS program, examine frequency control content of BAL series of Standards (including BAL-001-2 with respect to performance standards & MW balance concept, BAL-002-2 with respect to DCS, BAL-003-1.1 with respect to frequency bias, BAL-005-1 with repect to AGC, examine frequency disturbance related content of EOP series of Standards (including EOP-011-1 with respect to EEAs, generation redispatch for transmission loading relief & manual load shedding).

2.     Step through while describing sequence of events during 2/14/2008 disturbance event at Huntington generator in Western Interconnection.  Emphasize importance of recovering ACE following a generation loss (BAL-001-2), importance of recovering contingency reserve (BAL-002-2), consequences of single points of failure in protection systems & role of RC during major disturbance.

3.     Step through & describe sequence of events during 5/10/2011 disturbance event in Upper Penisula of Michigan.  Describe how TOPs & RCs coordinate outages of key transmission equipment as required by IRO-017-1.   Describe how lightning strike in high impedance grounded system caused loss of 2 - 138 kV lines & eventual collapse of area power system.  Describe & illustrate operation of UFLS (emphasizing PRC-006-2) & importance of generator UF tripping coordination.  Use synchrophasor frequency data to illustrate value of this type data in post-disturbance analysis.

 

ILA #2

Using actual voltage related disturbance events, describe & illustrate how voltage control process accomplished in NERC power systems

1.     Explain theory of voltage control including concept of reactive power, description of cause & effects of high & low voltage, difference between manual & dynamic reactive reserve, explanation of Ferranti voltage rise, explanation of load/voltage relationship, explanation & illustration of surge impedance loading, usage of capacitors & reactors, usage of transformers for voltage control, usage of generators for voltage control, definition of voltage stability & voltage collapse, description of 3 types of voltage collapse, usage of P-V & V-Q curves, examine voltage control related content of PRC & VAR series of Standards (including PRC-010-2 as related to UVLS, PRC-019-2 as relating to proper coordination of generation voltage related controls, PRC-023-4 & PRC-025-1 as related to unnessary limitations to generator & transmission Mvar loading ability, PRC-024-2 as related to proper settings for generator voltage controls & VAR-001-4.1 & VAR-002-4 as related to generator operator voltage control responsibilities).

2.     Step through & describe sequence of events during the 7/02/1996 disturbance event in Western Interconnection.  Emphasize importance of dynamic reactive reserves, need for accurate generator capability curves in study world, & formation of island boundaries.  Examine importance of accurate capability curves as addressed in Standard MOD-025-2.

3.     Step through & describe sequence of events during 8/14/2003 disturbance event in Eastern Interconnection.  Emphasize importance of accurate system operator communication (as required by COM-002-4), importance of situational awareness, & mechanics of impedance cascade.  Describe & illustrate relationship between voltage control & angle stability.  Describe how this disturbance moved electric industry from then existing Operating Policies to today's Reliability Standards.

4.     Step through & describe sequence of events during 3/13/1989 disturbance event in Quebec Interconnection.  Describe & illustrate concepts of CMEs, GICs & ESPs.  Explain purpose & usage of K-Indice & G-Scale.  Emphasize how loss of key voltage control equipment led to collapse of Hydro Quebec system.  Describe how Salem Nuclear UnitÕs GSU was damaged shortly after this event by GIC flow.  Examine content of EOP-010-1 with respect to TOPÕs & RCÕs GMD monitoring responsibilities & TPL-007-1 with respect to system planners GMD preparedness.

5.     Step through & describe sequence of events during 4/7/2015 disturbance event in Washington DC area of PJM.  Describe purpose, design & operation of lightning / surge arresters.  Describe & illustrate the operation of breaker failure schemes.  Describe purpose & illustrate operation of the DC control logic portion of a protection system including the impact of a loose wiring connection.  Describe how protection system testing as mandated by PRC-005-6 should have discovered this eventÕs DC wiring failure.  Describe and illustrate risk of single points of failure in protection schemes.

 

ILA #3

Using actual angle stability related disturbance events, describe & illustrate concepts of angle stability & angle instability.

1.     Explain theory of angle stability including explanation of factors that drive MW & MVar flow, explanation of synchronizing process, description of PST operation, definitions of angle stability & angle instability, description of how frequency differences lead to angle instability, use of phasor diagram to illustrate angle instability, description of steady-state, transient, & oscillatory instability using power angle curves, usage of braking resistors, fast protection & fast valving schemes, usage of OOS blocking & tripping relays, describe & illustrate usage of PSS, explain how RAS are often used to avoid angle instability & describe RAS related content of PRC series of Standards (including PRC-012-2, PRC-013-1, PRC-014-1, PRC-015-1, PRC-016-1, & PRC-017-1).  Explain purpose of PRC-026-1 as it relates to recoverable power swings.

2.     Step through & describe sequence of events during 6/25/1998 disturbance event in MAPP area of Eastern Interconnection.  Emphasize importance of recovering rapidly from IROL violation, unexpected operation of reclosing relays during disturbance events, & importance of coordinating OOS tripping & blocking relays.  Describe importance of recovering from IROL violation within TV value as described in TOP-001-3.

 

ILA #4

Examine how field personnel & system operator errors have resulted in or increased severity of power system disturbances.

1.     Step through & describe sequence of events during 6/14/2004 disturbance event in Arizona part of Western Interconnection.  Emphasize consequences of incorrect assumptions of CB position (open versus closed), dangers associated with voltage phase angle growth during extended faults & exceeding IROLs in disturbance conditions.  Emphasize importance of recovering from IROL violation within TV value as described in TOP-003-1 as related to overload on Western InterconnectionÕs Path #66.

2.     Step through & describe sequence of events during 2/26/2008 disturbance event in Florida part of Eastern Interconnection.  Emphasize consequences of protection engineers & system operators intentionally disabling primary & backup protection, impact of location related differences in transient frequency, & impact of frequency oscillations.  Review operation of Florida UFLS scheme in context of Standard PRC-006-2.  Describe need for trained system operators as stated in PER-003-1.

3.     Step through & describe sequence of events during 9/8/2011 disturbance event in southwest corner of Western Interconnection.  Emphasize importance of testing & understanding operation of RAS (PRC-012-2 & PRC-013-1), cause of large phase angles across open CBs, consequences of skipping steps in switching orders, & purpose of PRC-023-4 from equipment loadability perspective.  Describe compliance penalties issued to companies involved in this disturbance.