A. Itroductio. Title: Real Power Balacig Cotrol Performace 2. Number: BAL-00-0a 3. Purpose: To maitai Itercoectio steady-state frequecy withi defied limits by balacig real power demad ad supply i real-time. 4. Applicability: 4.. Balacig Authorities 5. Effective Date: October 23, 2007 B. Requiremets R. Each Balacig Authority shall operate such that, o a rollig 2-moth basis, the average of the clock-miute averages of the Balacig Authority s Area Cotrol Error (ACE) divided by B (B is the clock-miute average of the Balacig Authority Area s Frequecy Bias) times the correspodig clock-miute averages of the Itercoectio s Frequecy Error is less tha a specific limit. This limit ε 2 is a costat derived from a targeted frequecy boud (separately calculated for each Itercoectio) that is reviewed ad set as ecessary by the NERC Operatig Committee. ACE i AVG * Period F Bi The equatio for ACE is: 2 or AVG Period ACEi Bi 2 * F ACE (NI A NI S ) B (F A F S ) I ME where: NI A is the algebraic sum of actual flows o all tie lies. NI S is the algebraic sum of scheduled flows o all tie lies. B is the Frequecy Bias Settig (MW/0. Hz) for the Balacig Authority. The costat factor coverts the frequecy settig to MW/Hz. F A is the actual frequecy. F S is the scheduled frequecy. F S is ormally 60 Hz but may be offset to effect maual time error correctios. I ME is the meter error correctio factor typically estimated from the differece betwee the itegrated hourly average of the et tie lie flows (NI A ) ad the hourly et iterchage demad measuremet (megawatt-hour). This term should ormally be very small or zero. R2. Each Balacig Authority shall operate such that its average ACE for at least 90% of clockte-miute periods (6 o-overlappig periods per hour) durig a caledar moth is withi a specific limit, referred to as L. AVG ( i L miute ACE ) Page
where: L.65 ( Bi)( Bs) ε is a costat derived from the targeted frequecy boud. It is the targeted root-mea-square (RMS) value of te-miute average Frequecy Error based o frequecy performace over a give year. The boud, ε, is the same for every Balacig Authority Area withi a Itercoectio, ad B s is the sum of the Frequecy Bias Settigs of the Balacig Authority Areas i the respective Itercoectio. For Balacig Authority Areas with variable bias, this is equal to the sum of the miimum Frequecy Bias Settigs. R3. Each Balacig Authority providig Overlap Regulatio Service shall evaluate Requiremet M (i.e., Cotrol Performace Stadard or CPS) ad Requiremet M2 (i.e., Cotrol Performace Stadard 2 or CPS2) usig the characteristics of the combied ACE ad combied Frequecy Bias Settigs. R4. Ay Balacig Authority receivig Overlap Regulatio Service shall ot have its cotrol performace evaluated (i.e. from a cotrol performace perspective, the Balacig Authority has shifted all cotrol requiremets to the Balacig Authority providig Overlap Regulatio Service). C. Measures M. Each Balacig Authority shall achieve, as a miimum, Requiremet (CPS) compliace of 0%. CPS is calculated by covertig a compliace ratio to a compliace percetage as follows: CPS (2 - ) * 0% The frequecy-related compliace factor,, is a ratio of all oe-miute compliace parameters accumulated over 2 moths divided by the target frequecy boud: ( ) 2 moth 2 where: ε is defied i Requiremet R. The ratig idex 2-moth is derived from 2 moths of data. The basic uit of data comes from oe-miute averages of ACE, Frequecy Error ad Frequecy Bias Settigs. A clock-miute average is the average of the reportig Balacig Authority s valid measured variable (i.e., for ACE ad for Frequecy Error) for each samplig cycle durig a give clockmiute. ACE B clock-miute ACE samplig cyclesi clock-miute samplig cyclesi clock-miute -B F Fclock-miute samplig cyclesi clock-miute samplig cyclesi clock-miute Page 2
The Balacig Authority s clock-miute compliace factor () becomes: ACE B clock -miute * Fclock-miute clock-miute Normally, sixty (60) clock-miute averages of the reportig Balacig Authority s ACE ad of the respective Itercoectio s Frequecy Error will be used to compute the respective hourly average compliace parameter. clock-hour clock-miute clock-miute samples i hour The reportig Balacig Authority shall be able to recalculate ad store each of the respective clock-hour averages ( clock-hour average-moth) as well as the respective umber of samples for each of the twety-four (24) hours (oe for each clock-hour, i.e., hour-edig (HE) 00, HE 0200,..., HE 2400). clock-hour average-moth [( days-i-moth clock-hour [ )( oe-miute samplesi clock-hour oe-miute samplesi clock-hour days-i moth ] )] moth hours-i-day [( clock-hour average-moth [ )( oe-miute samples i clock-hour averages oe-miute samples i clock-hour averages hours-i day ] )] The 2-moth compliace factor becomes: 2-moth 2 ( moth-i i 2 i [ )( ( oe-miute samples i moth ) (oe-miute samples i moth)-i ] i )] I order to esure that the average ACE ad Frequecy Deviatio calculated for ay oemiute iterval is represetative of that oe-miute iterval, it is ecessary that at least 50% of both ACE ad Frequecy Deviatio samples durig that oe-miute iterval be preset. Should a sustaied iterruptio i the recordig of ACE or Frequecy Deviatio due to loss of telemeterig or computer uavailability result i a oe-miute iterval ot cotaiig at least 50% of samples of both ACE ad Frequecy Deviatio, that oe-miute iterval shall be excluded from the calculatio of CPS. M2. Each Balacig Authority shall achieve, as a miimum, Requiremet R2 (CPS2) compliace of 90%. CPS2 relates to a boud o the te-miute average of ACE. A compliace percetage is calculated as follows: Page 3
CPS2 Violatios ( Total Periods Uavailable Periods ) moth moth moth *0 The violatios per moth are a cout of the umber of periods that ACE clock-te-miutes exceeded L. ACE clock-te-miutes is the sum of valid ACE samples withi a clock-temiute period divided by the umber of valid samples. Violatio clock-te-miutes 0 if ACE samples i -miutes L if ACE samples i -miutes > L Each Balacig Authority shall report the total umber of violatios ad uavailable periods for the moth. L is defied i Requiremet R2. Sice CPS2 requires that ACE be averaged over a discrete time period, the same factors that limit total periods per moth will limit violatios per moth. The calculatio of total periods per moth ad violatios per moth, therefore, must be discussed joitly. A coditio may arise which may impact the ormal calculatio of total periods per moth ad violatios per moth. This coditio is a sustaied iterruptio i the recordig of ACE. I order to esure that the average ACE calculated for ay te-miute iterval is represetative of that te-miute iterval, it is ecessary that at least half the ACE data samples are preset for that iterval. Should half or more of the ACE data be uavailable due to loss of telemeterig or computer uavailability, that te-miute iterval shall be omitted from the calculatio of CPS2. D. Compliace. Compliace Moitorig Process.. Compliace Moitorig Resposibility Compliace Moitor: British Columbia Utilities Commissio Compliace Moitor s Admiistrator: Wester Electricity Coordiatig Coucil.2. Compliace Moitorig Period ad Reset Timeframe Oe caledar moth..3. Data Retetio The data that supports the calculatio of CPS ad CPS2 (Appedix -BAL-00-0) are to be retaied i electroic form for at least a oe-year period. If the CPS ad CPS2 data for a Balacig Authority Area are udergoig a review to address a questio that has bee raised regardig the data, the data are to be saved beyod the ormal retetio period util the questio is formally resolved. Each Balacig Authority shall retai for a Page 4
rollig 2-moth period the values of: oe-miute average ACE (ACE i ), oe-miute average Frequecy Error, ad, if usig variable bias, oe-miute average Frequecy Bias..4. Additioal Compliace Iformatio Noe. 2. Levels of No-Compliace CPS 2.. Level : The Balacig Authority Area s value of CPS is less tha 0% but greater tha or equal to 95%. 2.2. Level 2: The Balacig Authority Area s value of CPS is less tha 95% but greater tha or equal to 90%. 2.3. Level 3: The Balacig Authority Area s value of CPS is less tha 90% but greater tha or equal to 85%. 2.4. Level 4: The Balacig Authority Area s value of CPS is less tha 85%. 3. Levels of No-Compliace CPS2 3.. Level : The Balacig Authority Area s value of CPS2 is less tha 90% but greater tha or equal to 85%. 3.2. Level 2: The Balacig Authority Area s value of CPS2 is less tha 85% but greater tha or equal to 80%. 3.3. Level 3: The Balacig Authority Area s value of CPS2 is less tha 80% but greater tha or equal to 75%. 3.4. Level 4: The Balacig Authority Area s value of CPS2 is less tha 75%. E. Regioal Differeces The ERCOT Cotrol Performace Stadard 2 Waiver approved November 2, 2002. Page 5
Appedix -BAL-00-0a CPS ad CPS2 Data CPS DATA Descriptio Retetio Requiremets ε A costat derived from the targeted frequecy boud. This umber is the same for each Balacig Authority Area i the Itercoectio. Retai the value of ε used i CPS calculatio. ACE i The clock-miute average of ACE. Retai the -miute average values of ACE (525,600 values). B i The Frequecy Bias of the Balacig Authority Area. Retai the value(s) of B i used i the CPS calculatio. F A The actual measured frequecy. Retai the -miute average frequecy values (525,600 values). F S Scheduled frequecy for the Itercoectio. Retai the -miute average frequecy values (525,600 values). CPS2 DATA Descriptio Retetio Requiremets V ε B i B s U Number of icidets per hour i which the absolute value of ACE clock-te-miutes is greater tha L. A costat derived from the frequecy boud. It is the same for each Balacig Authority Area withi a Itercoectio. The Frequecy Bias of the Balacig Authority Area. The sum of Frequecy Bias of the Balacig Authority Areas i the respective Itercoectio. For systems with variable bias, this is equal to the sum of the miimum Frequecy Bias Settig. Number of uavailable te-miute periods per hour used i calculatig CPS2. Retai the values of V used i CPS2 calculatio. Retai the value of ε used i CPS2 calculatio. Retai the value of B i used i the CPS2 calculatio. Retai the value of B s used i the CPS2 calculatio. Retai the -miute miimum bias value (525,600 values). Retai the umber of -miute uavailable periods used i calculatig CPS2 for the reportig period. Page 6
Iterpretatio of Requiremet Appedix 2 Effective Date: August 27, 2008 (U.S.) Request: Does the WECC Automatic Time Error Cotrol Procedure (WATEC) violate Requiremet of BAL-00-0? Iterpretatio: Requiremet of BAL-00 Real Power Balacig Cotrol Performace, is the defiitio of the area cotrol error (ACE) equatio ad the limits established for Cotrol Performace Stadard (CPS). BAL-00-0 R. Each Balacig Authority shall operate such that, o a rollig 2-moth basis, the average of the clock-miute averages of the Balacig Authority s Area Cotrol Error (ACE) divided by B (B is the clock-miute average of the Balacig Authority Area s Frequecy Bias) times the correspodig clock-miute averages of the Itercoectio s Frequecy Error is less tha a specific limit. This limit ε2 is a costat derived from a targeted frequecy boud (separately calculated for each Itercoectio) that is reviewed ad set as ecessary by the NERC Operatig Committee. The WATEC procedural documets ask Balacig Authorities to maitai raw ACE for CPS reportig ad to cotrol via WATEC-adjusted ACE. As log as Balacig Authorities use raw (uadjusted for WATEC) ACE for CPS reportig purposes, the use of WATEC for cotrol is ot i violatio of BAL-00 Requiremet. Page 7