Generating System Data and Model Guidelines. Determination and Report

Transcription

1 Natinal Electricity Market Management Cmpany Limited ABN Generating System Data and Mdel Guidelines Determinatin and Reprt Prepared by: Pwer System Planning and Develpment Versin: 1.0 Date: 29 February 2008 Page 1 f 71

2 Executive Summary This cnsultatin was cnducted in respnse t changes t the Natinal Electricity Rules [1] that came int effect n 15 March Sme f the changes brught abut by this change included the replacement f Schedules S5.5.1 and S5.5.2 with a Generating System Design Data Sheet, a Generating System Setting Data Sheet and Generating System Mdel Guidelines that NEMMCO was required t develp under Rule S5.5.7 in accrdance with the Rules cnsultatin prcedures. NEMMCO is required by Rule S5.5.7 t develp and publish the Generating System Design Data Sheet, Generating System Setting Data Sheet and the Generating System Mdel Guidelines by 1 March Fr the first stage f the cnsultatin, three dcuments were prepared: an Issues Paper; draft Generating System Design and Setting Data Sheets (Data Sheets); and draft Generating System Mdel Guidelines (Mdel Guidelines). Six valid submissins were received in respnse t the First Stage Ntice f cnsultatin frm the fllwing parties: ALSTOM (Switzerland) Ltd; Clean Energy Cuncil; TransGrid; CitiPwer / Pwercr Australia; Suzln Energy Australia Pty Ltd; and Raring 40s. Tw valid submissins were received in respnse t the Secnd Stage Ntice f cnsultatin frm the fllwing parties: Vestas Australia; Clean Energy Cuncil. NEMMCO has revised the draft Data Sheets and draft Mdel Guidelines. The significant utcmes are: Fr the Data Sheets: n additinal generating system technlgies have been added t the draft Data Sheets; changes and additins t symbl names; revisin f sme timing classificatins (S, D, R1 and R2 classificatins) fr prvisin f infrmatin; crrectin t specificatin f fault current infrmatin; allwance fr R2 parameters t be determined fr a range f generating units thrugh typetests 1, under certain circumstances; a request fr infrmatin regarding any assumptins used t determine fault current infrmatin; 1 That is, a test carried ut n a single unit as representative f the perfrmance f all identical units. Page 2 f 71

3 remval f the R2 classificatin fr fault ride-thrugh cntrl schemes, where ff-site tests r factry tests (i.e. R1 data) can be shwn t be representative f the plant installed n-site; a reference t Data Sheet changes that may arise ut f an apprval by NEMMCO f an alternative mdel prvided under Rule S5.2.4(c)(2); and additins, deletins and clarificatins t specific data items. Fr the Mdel Guidelines: remval f several accuracy requirements fr the transient stability mdels that were identified as superfluus r which placed t much reliance n the accuracy f the pwer system mdel; remval f the need fr medium and lng term mdels, relying n the data prvided with the Data Sheets t prvide relevant infrmatin fr these types f studies; remval f the need fr subsynchrnus resnance mdels, relying n the data prvided with the Data Sheets t prvide relevant infrmatin fr these types f studies; remval f the need fr harmnic mdel infrmatin; a decisin by NEMMCO that there is insufficient evidence at this stage that electr-magnetic transient mdels are required by NEMMCO r Netwrk Service Prviders; a decisin by NEMMCO that (summarised): generating unit mdels are required fr all generating systems. Other plant in the generating system must be mdelled explicitly these must be validated mdels; where there is a significant cmputatinal burden by mdelling each generating unit within a generating system, NEMMCO and the NSP wuld, in the first instance, scale the generating unit mdel by the number f similar generating units; and a Generatr may chse t apply t NEMMCO and the NSP t prvide a mdel that aggregates the generating unit mdels within a generating system int a single equivalent generating unit. This wuld be prvided in additin t the generating unit mdel this mdel need nt be validated, but must be cnfirmed against the generating unit mdel; replacement f the list f pwer system simulatin sftware prducts held by NEMMCO (fr which unencrypted mdel surce cde infrmatin must be prvided under Rule S5.2.4(b)(6)) with a reference t NEMMCO s website, where that list will reside; and a statement regarding the requirement fr cnsistency between varius frms f mdel infrmatin prvided by a Generatr r cnnectin applicant, as required by the Data Sheets and Mdel Guidelines. Page 3 f 71

4 Table f Cntents 1 MATTER UNDER CONSULTATION THE CONSULTATION PROCESS BACKGROUND TO MATTER UNDER CONSULTATION REQUIREMENT FOR CONNECTION APPLICANT TO PROVIDE TECHNICAL DATA EXTENT OF DATA PROVISION REQUIREMENTS CONSIDERATION OF CONSULTATION SUBMISSIONS LIST OF SUBMISSIONS RECEIVED MEETINGS CONSIDERATION OF SUBMISSIONS NEED TO CHANGE THE FORMAT OF THE DATA SHEETS ADDITIONAL TECHNOLOGIES EFFECTIVENESS AND APPROPRIATENESS OF THE DATA SHEET STRUCTURE DATA PROVISION WHEN DATA SHEETS ARE INAPPROPRIATE ARRANGEMENT OF DESIGN AND SETTING DATA SCOPE OF STUDIES FOR WHICH THE DATA SHEETS ARE USED IMPEDANCE MODELLING WITHIN A GENERATING SYSTEM FAULT MODELLING FOR GENERATORS WITH POWER ELECTRONIC GRID INTERFACES FORMAT OF HARMONIC INFORMATION WHERE AN ACCEPTABLE PLANT STANDARD DOES NOT EXIST NEED FOR ADDITIONAL COMPONENTS IN THE DATA SHEETS DATA SHEET COMPONENT SUITABILITY FOR RESPONSE TO POWER SYSTEM DISTURBANCE REQUIREMENTS FOR SUB-SYNCHRONOUS RESONANCE MODELS TIMING DESIGNATION OF DATA SHEETS DATA CHANGES IN REQUIREMENTS OF THE DATA SHEETS OTHER STANDARDS AND GRID CODES TO BE USED AS REFERENCES MISSING DETAILS FROM THE MODEL GUIDELINES FURTHER GUIDANCE ON OSCILLATORY STABILITY MODELLING ALLOWANCE TO VARY THE REQUIREMENTS FOR MODEL PERFORMANCE GENERATING UNIT VERSUS SYSTEM MODELLING MORE DIFFICULT ASPECTS OF ACCURACY REQUIREMENTS FOR MODELS STAGING OF TESTS RATHER THAN RELIANCE ON SYSTEM INCIDENTS RELIANCE ON UNIT MODEL FOR VALIDATION OF GENERATING SYSTEM MODEL MODELLING GUIDELINES DOCUMENTATION ADEQUACY NEED FOR EMT MODELS OTHER ISSUES GENERIC DYNAMIC MODELS FOR WINDFARMS CONFIDENTIALITY LONG TIME FRAME MODELLING MODEL DESCRIPTION WIND VARIABILITY EFFECTS ACCURACY OF WIND TURBINE MODELS UNDER CHANGING WIND CONDITIONS DEFINITION OF DAMPING IEEE STANDARD MODELS MODEL TIME-STEP REQUIREMENTS GRANDFATHERING OF MODELLING STANDARDS INCOMPLETE SECTIONS OF THE GENERATING SYSTEM MODEL GUIDELINES SUB-TRANSIENT REACTANCE FOR FAULT ANALYSIS INCLUSION OF TSAT IN THE MODEL GUIDELINES INCLUSION OF WIND STRENGTH AS AN INPUT TO A WIND TURBINE MODEL FINAL SETTLING VALUE OF THE MODEL AFTER A DISTURBANCE FINAL SETTLING VALUE IN MEDIUM AND LONG TERM STUDIES...60 Page 4 f 71

5 6.16 ACCURACY REQUIREMENTS IN MEDIUM AND LONG TERM STUDIES PROVISION OF AN ALTERNATIVE MODEL R2 TESTING OF PARAMETERS REPETITION OF TESTS COMBINED MODELS VALIDATION TESTS ISSUES RAISED BY NEMMCO THE LIST OF GENERATING UNITS TO WHICH INFORMATION APPLIES SYNCHRONOUS MACHINE IMPEDANCES ASYNCHRONOUS MACHINE TORQUE/SPEED AND EQUIVALENT CIRCUIT INFORMATION MISSING TIMING CLASSIFICATIONS SPECIFYING SOFTWARE PRODUCT VERSIONS CLARIFICATION OF RELATIONSHIP BETWEEN DATA SHEETS AND MODEL GUIDELINES DETERMINATION REFERENCES...70 SCHEDULES...71 Page 5 f 71

6 1 Matter under cnsultatin Schedule 5.5 f the Natinal Electricity Rules (Rules) cvers the technical data that must be prvided t supprt applicatins fr cnnectin t the natinal grid, and therwise requested by a Netwrk Service Prvider (NSP) r NEMMCO under Rule S5.2.4(a). Clause S5.5.7 requires NEMMCO t develp and publish a Generating System Design Data Sheet, a Generating System Setting Data Sheet (Data Sheets) and Generating System Mdel Guidelines (Mdel Guidelines) as fllws: S5.5.7: (a) NEMMCO must, subject t paragraph (b), develp and publish by 1 March 2008, in accrdance with the Rules cnsultatin prcedures: (1) a Generating System Design Data Sheet describing, fr relevant technlgies, the generating system design parameters f generating units and generating systems including plant cnfiguratins, impedances, time cnstants, nn-linearities, ratings and capabilities, t be prvided under clauses S5.2.4 and this schedule 5.5; (2) a Generating System Setting Data Sheet describing, fr relevant generatin and cntrl system technlgies, the prtectin system and cntrl system settings f generating units and generating systems including cnfiguratins, gains, time cnstants, delays, deadbands, nnlinearities and limits, t be prvided under clauses S5.2.4 and this schedule 5.5; and (3) Generating System Mdel Guidelines describing, fr relevant generatin and cntrl system technlgies, NEMMCO s requirements when develping mathematical mdels fr generating units and generating systems, including the impact f their cntrl systems and prtectin systems n pwer system security, and there must be a Generating System Design Data Sheet, Generating System Setting Data Sheet and Generating System Mdel Guidelines in place at all times after that date. The Data Sheets, develped in accrdance with this Rule, replace Schedules and that were applicable prir t 15 March Rule S5.5.7 als stipulates that: (b) When develping and publishing the Generating System Design Data Sheet, Generating System Setting Data Sheet and Generating System Mdel Guidelines under paragraph (a), NEMMCO must have regard t the purpse f develping and publishing the sheets and guidelines which is t: (1) allw generating units and generating systems t be mathematically mdelled by NEMMCO in lad flw and dynamic stability assessments with sufficient accuracy t permit: (i) (ii) (iii) the pwer system perating limits fr ensuring pwer system security t be quantified with the lwest practical safety margins; prpsed access standards and perfrmance standards f generating units and generating systems t be assessed; and settings f cntrl systems and prtectin systems f generating units, generating systems and netwrks t be assessed and quantified fr maximum practical perfrmance f the pwer system; and (2) identify fr each type f data its categry in terms f clause S The categry specified in Rule S5.5.7(b)(2) relates t the fllwing data categries defined in Rule S5.5.2: Page 6 f 71

7 Standard Planning Data (S); Detailed Planning Data (D); r Registered Data (R1 pre-cnnectin, R2 pst-cnnectin). Page 7 f 71

8 2 The Cnsultatin Prcess Fllwing is an utline f the cnsultatin prcess. Prcess Date Ntice f First Stage f Rules Cnsultatin issued 6 September 2007 Clsing date fr submissins received in respnse t the Ntice f First Stage f Rules Cnsultatin 18 Octber 2007 Publicatin f Draft Determinatin and Reprt and issue f Ntice Of 13 December 2007 Secnd Stage f Rules Cnsultatin inviting submissins in respnse t the Draft Determinatin and Reprt Clsing date fr submissins received in respnse t the Draft 22 January 2008 Determinatin and Reprt Publicatin f this Determinatin and Reprt 29 February 2008 Page 8 f 71

9 3 Backgrund t matter under cnsultatin This cnsultatin is being cnducted in respnse t Rule changes that came int effect n 15 March f As part f this Rule change, frmer Schedules S5.5.1 and S5.5.2 were deleted frm the Rules, and have been replaced by the Data Sheets. NEMMCO is required by Rule S5.5.7 t develp and publish the Data Sheets and the Mdel Guidelines by 1 March Requirement fr cnnectin applicant t prvide technical data The Rules mandate the prvisin f the technical data cvered by Schedule 5.5. Prvisin f data is required f Cnnectin Applicants and n an nging basis by Generatrs: Rule 5.3.3(c)(3) requires an NSP t detail the list f technical data required t supprt an applicatin t cnnect, which will generally be in the nature f the infrmatin set ut in Schedule 5.5, but may be varied by the NSP as apprpriate t suit the size and cmplexity f the facility t be cnnected. Rule requires a Generatr prpsing t alter a cnnected generating system t prvide technical infrmatin listed in the Data Sheets as well as the impact f the alteratin n the generating system perfrmance n the applicable access standards. Rule S5.2.4(a) requires that a Generatr r any persn negtiating a cnnectin agreement must prvide technical data specified in Schedule 5.5 n request by NEMMCO r an NSP (there are sme qualificatins t this requirement in Rules S5.5.5 and S5.5.6, relating t Generatrs wh have generating systems cmprising asynchrnus generating units r generating systems f less than 30MW capacity). Rule S5.2.4(b) thrugh (d) require that a Generatr whse plant has a cmbined nameplate rating f 30MW r mre must prvide a dynamic mdel f the generating system, in the frm f bth functinal blck diagrams and surce cde. The mdel must be prvided with the applicatin t cnnect, r three mnths prir t cmmissining (whichever is earlier), and must be updated fllwing the cmpletin f cmmissining tests r ther cmpliance tests, r when plant is altered. Rule S5.5.3 requires an NSP t initiate a peridic review f the data t ensure its cntinued accuracy and relevance. 3.2 Extent f Data Prvisin Requirements Under Rule S5.2.4(a), NEMMCO r an NSP may request the prvisin by a Cnnectin Applicant r Generatr f all data specified in the Data Sheets, and the Cnnectin Applicant r Generatr must prvide that data. Rules S5.5.5 and S5.5.6 limit the applicatin f this requirement as fllws: Rule S5.5.5: Generatrs wh have generating systems cmprising asynchrnus generating units are exempted frm prviding data the NSP cnsiders nt t be relevant t the asynchrnus generatin; and Rule S5.5.6: Embedded generating units r generating systems f less than r equal t 30MW capacity are required t submit less registered system planning data and less registered data than is indicated in the Data Sheets and Mdel Guidelines, but must prvide the data if reasnably required by the NSP r NEMMCO. Rule S5.2.4 establishes that dynamic mdels must be develped in accrdance with the Mdel Guidelines, except where therwise agreed with NEMMCO. Rule prvides that an NSP may Page 9 f 71

10 require ccasinal testing f a generating unit fr the purpse f determining mdel parameters r t assess perfrmance and that NEMMCO may direct an NSP t require testing if NEMMCO cnsiders that existing infrmatin is inadequate t determine mdel parameters. Page 10 f 71

11 4 Cnsideratin f cnsultatin submissins 4.1 List f submissins received NEMMCO received six submissins in respnse t the Ntice f First Stage f Rules Cnsultatin. Fllwing is a list f respndents: Respndent ALSTOM (Switzerland) Ltd Clean Energy Cuncil TransGrid CitiPwer Pty & Pwercr Australia Pty Ltd (cmbined submissin) Suzln Energy Australia Pty Ltd Raring 40s Participant Type r Other Rle Interested Party Interested Party Transmissin Netwrk Service Prvider Market Custmer, Distributin Netwrk Service Prvider, Special Participant Distributin Operatr Distributin Netwrk Service Prvider, Special Participant Distributin Operatr Interested Party Generatr All f these submissins were published n NEMMCO s website n the same date that the Draft Determinatin and Reprt was released. Fllwing is a list f respndents fr the Secnd Stage f the cnsultatin: Respndent Vestas Clean Energy Cuncil Participant Type r Other Rle Interested Party Interested Party Bth f these submissins were published n NEMMCO s website n the same date that this Determinatin was released. 4.2 Meetings Raring 40s requested a meeting, which tk place n 3 December The meeting clarified the issues raised in the Raring 40s submissin and discussed NEMMCO s cnsideratin f Raring 40s issues in Sectin 5. There were n meetings requested frm the Secnd Stage f the cnsultatin. Page 11 f 71

12 5 Cnsideratin f Submissins The fllwing Sectins present the specific cmments made in the submissins in terms f: Sectins 5.1 t 5.24 the issues raised in the Issues Paper (numbered and quted frm the Issues Paper); Sectin 6 additinal issues raised in the submissins; and Sectin 7 further issues raised by NEMMCO. In general, submissins have been allcated t the issues (1 t 24) they were specified as addressing. Where a general cmment was made that was nt assigned t a particular issue, NEMMCO placed the cmment under the issues where it mst reasnably fitted and, at times, t several issues. The Clean Energy Cuncil s submissin fr the Secnd Stage f the cnsultatin raised n majr issues and hence is nt specifically referenced belw. That submissin cmmented that the Cuncil expects that the Data Sheets and Mdel Guidelines will evlve ver time as systems change and technlgies mature. NEMMCO agrees that this is likely t be the case, and will carry ur further Rules cnsultatins t mdify r expand the Data Sheets r Mdel Guidelines at apprpriate times. 5.1 Need t change the frmat f the Data Sheets Issue 1 Frm NEMMCO s perspective, the style and frmat f specificatin f plant parameters in the Data Sheets has wrked adequately in the past. Is there a need t change the frmat? What frmat is recmmended? Please prvide reasns fr, and the advantages f, any prpsed frmat change Submissins: Alstm: Alstm des nt see a need t change the draft frmat. Hwever, prviding symbls fr each parameter wuld help when making references. TransGrid: TransGrid agrees that the there is n need fr a change in the frmat f the Data Sheets NEMMCO s cnsideratin and decisin Neither Cnsulted Persn saw a need t change the frmat f the Data Sheets. NEMMCO will retain the current style and frmat. Alstm requested the prvisin f symbls fr all parameters in the Data Sheets. Symbls have been used when these were seen t be either standard symbls, r at least typical symbls, used fr the particular parameters described in the Data Sheets. Symbls have been added t the Data Sheets, where pssible, t reflect Alstm s request fr additinal parameter symbls. 5.2 Additinal Technlgies Issue 2 Shuld any ther technlgies be explicitly addressed in these Data Sheets? In terms f thse ther technlgies what evidence is there that wuld supprt their inclusin in the Data Sheets (e.g. existing installatins r nes under develpment)? Page 12 f 71

13 5.2.1 Submissins: Suzln: The fllwing technlgy type is currently nt represented in Table 1, s we wuld suggest the fllwing rw be inserted in the WIND sectin: Fuel Prime mver cntrl Type f generatin Grid interface Pwer system cntrl Wind Pitch Cntrller and Variable Slip Active Pwer Cntrl Asynchrnus (variable rtr resistance) Transfrmer System vltage r reactive pwer cntrl frm reactive plant This is required t accmmdate wind farms based n Suzln s S88 WTGs, with several prjects installing this equipment currently under develpment. CitiPwer/Pwercr: Wave and tidal generatin shuld be included. There are trials underway in Australia, and it is a prven generatin elsewhere s it wuld be beneficial t be included. TransGrid: TransGrid is nt aware f any ther generating technlgy that needs t be explicitly addressed in the Data Sheets NEMMCO s cnsideratin and decisin The Issues Paper suggested a number f technlgies that culd be included in the Data Sheets. Suzln suggested an additinal frm f wind turbine generatr be added t the table in the Data Sheets. Suzln s recmmended additin will be made t the Data Sheets. CitiPwer/Pwercr suggested the additin f tidal generatin. Althugh there are tidal generatin schemes in existence (ne scheme has a capacity f 240MW), NEMMCO wuld prefer nt t speculate n the type technlgy that wuld be used fr the size f prject that wuld warrant a dynamic mdel. When a prject f significant size lks like cming t fruitin, NEMMCO will need t establish the mdel and cnsult with the prpnent. It is expected that the Data Sheets may already cver many aspects f this type f plant, assuming that cnventinal generatr technlgy is used and depending n the type f turbine used. The prcesses within the Data Sheets and the Rules allw fr the pssibility t prvide infrmatin in an alternative frm. If necessary, additinal Data Sheets culd be added fllwing a Rules cnsultatin. At this time, NEMMCO will nt include Data Sheets specific t tidal generatin. 5.3 Effectiveness and Apprpriateness f the Data Sheet Structure Issue 3 Is the structure f the draft Data Sheets effective and apprpriate? If nt what alternative structure wuld be effective and apprpriate? Des the abve list (sectin 4.3 [f the Issues Paper]) describe the mdular structure apprpriately? Has anything been missed in the list abve? This shuld apply fr a technlgy currently implemented in a generating system in the NEM, r emerging technlgies that are likely t lead t generating systems f 30MW r mre in the next 5 years. Is there any infrmatin listed under sectin 4.3 [f the Issues Paper] (r in the draft Data Sheets) that culd nt be btained by a Cnnectin Applicant r Generatr? (Please be specific abut what infrmatin, and when it might be available) Page 13 f 71

14 5.3.1 Submissins: CitiPwer/Pwercr: In general the requested infrmatin cvers the prtectin requirements. It is suggested that: The different sheets fr the different prtectin systems are all very similar and shuld be cmbined nt ne sheet but with the different systems identified and described. There must be a schematic diagram submitted t shw the different prtectin systems and what their inputs are and what they act upn (trips what). There must be a diagram f the earthing arrangement fr the Pwer Statin. There is n mentin f parallel capacitr bank cntrls if ne is installed fr pwer factr r harmnic cntrl. It is pssible that a fixed bank and nt an SVC culd be installed. Raring 40s: The generatr data sheets cntain fields fr generatr pitch systems including Cp curves. It is nted that there is insignificant respnse frm the pitch systems fr the system events studies in the transient time frame. As such pitch system mdelling is nt necessary fr mdelling the respnse f wind farms t pwer system disturbances. The nly circumstance under which pitch systems will mve t a significant degree is when the wind speed changes. As wind speed is nt a variable in pwer system mdels, there is n value in attempting t mdel the dynamic perfrmance f pitch systems. It shuld als be nted that manufacturers seem quite sensitive abut pitch system designs and mre s abut blade design. Fr this reasn we expect string resistance t any requirement t prvide such data. Given the lack f demnstrated need fr this data, and the reluctance f suppliers t prvide this data, we suggest that the infrmatin n pitch systems shuld be mitted frm the generating system data sheets until a suitable case is made fr their inclusin. TransGrid: TransGrid believes that: The structure f the draft Data Sheets is effective and apprpriate. The list in sectin 4.3 describes the mdular structure apprpriately. Generatrs wuld knw whether the list is cmplete. Generatrs wuld knw better whether any the infrmatin listed in sectin 4.3 culd nt be prvided. The fllwing submissin was received during the Secnd Stage f the cnsultatin: Vestas: It is acknwledged that sme cnsideratin was undertaken with the Draft Determinatin issued n December 2007 in relatin t the tpic f generatr pitch systems. In reference t this tpic it shuld be nted that generatr pitch systems are nt nrmally cnsidered in the develpment f transient mdels as the time cnstant perid fr pitch system perfrmance relevance is utside the bundaries f transient mdels and d nt bear significant impact n the turbine perfrmance. With this cnsideratin in mind the questin may turn t the relevance f such data. In relatin t (viii) auxiliary cmpensatin equipment there is an issue. Usually there is a current surce dynamic inverter based reactive cmpensatin system (rather than a vltage surce cnverter). It may be that a new sectin titled current surce dynamic inverter based cmpensatin system data culd be put int the data sheet additinally t vltage surce cnverter NEMMCO s cnsideratin and decisin TransGrid submits that the Data Sheet structure is effective and apprpriate. CitiPwer/Pwercr suggested that the prtectin system sheets shuld be cmbined due t their similarity. NEMMCO agrees that the frmat is similar, but prefers t keep sme f them separate t emphasise the different specific categries f prtectin that need t be prvided: specific generating unit prtectins: Page 14 f 71

15 typical synchrnus generating unit prtectin systems, which include the types f prtectin systems required under Rule S ; asynchrnus generating unit prtectin systems required under Rule S ; crwbar prtectins which are internal t sme wind turbine and similar technlgies that have pwer electrnic cntrls; and ther relevant prtectin systems. Anti-islanding prtectin systems (referenced in Rule S (c)) will be cmbined under Other prtectin systems, as this is sufficiently general t fit under that heading. While generally agreeing with the Data Sheet structure, CitiPwer/Pwercr suggested the fllwing additins: (i) A schematic diagram f prtectin systems shwing the input and the effect f the prtectin; (ii) A diagram shwing the earthing arrangements fr a pwer statin; and (iii) A sectin regarding parallel capacitr banks, Item (i) is cnsidered t be already addressed by the Data Sheets with the reference t Diagram under the Units heading. Item (iii) is addressed by Sectin 15.1 f the Data Sheets. T satisfy item (ii), an additinal requirement fr earthing arrangement and impedances has been added t the single line diagram under Sectin 6 f the Data Sheets ( Generating system (Pwer Statin) ). This is cnsidered t meet the general requirements f Rule S5.5.7(b)(1) ( t allw generating systems t be mathematically mdelled by NEMMCO in lad flw and dynamic stability assessments ), by allwing an assessment f zer sequence cnnectins and impedances. Raring 40s and Vestas suggest that generatr pitch systems are t slw t respnd in transient timeframes. Raring 40s further submits that there will be strng manufacturer reluctance t prvide wind-speed/turbine pitch infrmatin. NEMMCO s review f the literature, including typical mdels shws this t be necessary (e.g. mdels prvided fr DIgSILENT s Pwerfactry sftware and Siemens Pwer Technlgies Incrprated s PSS/E sftware). Cnsidering the speed f respnse f pitching, the impact n simulatin accuracy may nt be negligible after a fault. NEMMCO will t retain the requirement fr aerdynamic mdels and pitch cntrller mdels t be prvided. NEMMCO ntes Vestas suggestin t add infrmatin requirements fr current surce cnverter devices and will adjust the Data Sheets accrdingly. 5.4 Data Prvisin when Data Sheets are inapprpriate Issue 4 Hw shuld the Data Sheets cater fr the situatin in which the plant technlgy des nt fit well with the data sheet mdel? Submissins: TransGrid: TransGrid has limited experience with alternative pwer surces and is therefre unable t make a suggestin. Clean Energy Cuncil: (als cvered under Issue 18, Sectin 5.18) Given the evlving nature f many renewable energy generatrs, it will nt always be practical t be fully prescriptive n the data required. Flexibility is very imprtant in the prvisin f infrmatin where it may nt be available, cannt be Page 15 f 71

16 determined accurately r is impractical t btain, and the lack f infrmatin nly has immaterial impacts n the mdelled utcmes. Often when the infrmatin nt available a cnservative estimate can be made in mdel parameters, s that pwer system security is nt cmprmised, and the prpnent is still able t demnstrate cmpliance. The fllwing submissin was received during the Secnd Stage f the cnsultatin: Vestas: In circumstances where the plant technlgy des nt fit well with the data sheet mdel, the slutin is nt t seek NEMMCO s written apprval. Alternatively, a data sheet with typical infrmatin needs may be ffered in the Data Sheet whereby new data may be entered and then submitted t NEMMCO. Flexibility is warranted here as new technlgies may require different parameters t adequately describe perfrmance NEMMCO s cnsideratin and decisin The Clean Energy Cuncil stresses the imprtance f flexibility arund data prvisin, especially where technlgy is under rapid develpment. The prvisin f cnservative data was suggested as a way f achieving a suitable utcme fr bth a prpnent and NEMMCO. There are already mechanisms available fr infrmatin t be prvided in alternative frms, shwing justificatin. If the impact can be shwn t be immaterial, then there may be scpe t allw sme flexibility, althugh NEMMCO des nt want t discunt the significant effrt that may be required t demnstrate this, particularly: ver the pssible range f cnditins that the generating system may be required t perate, including, fr example, netwrk plant utage cnditins and a range f different cntingency events; the ptential fr cnservative parameters t lead t pessimistic utcmes in sme instances and ptimistic utcmes in thers; and in terms f the impacts that the inaccuracy may have n the determinatin f netwrk limits, including stability limits. The use f inaccurate parameters t shw cnservative perfrmance can have unintended cnsequences ver the full range f pwer system cnditins. Gd mdelling accuracy f generating systems is an imprtant aspect in ensuring that the generating system is nt restricted in its peratin and netwrk capability is nt degraded unnecessarily. The Issues Paper presented tw alternatives t allw nn-standard infrmatin t be prvided: 1. By applicatin t NEMMCO t allw infrmatin t be prvided in an alternative manner; and 2. Data Sheets that were in a generic frm. Vestas suggests that the Generatr shuld be able t prvide alternative infrmatin withut specific written apprval by NEMMCO, and prpses that a Data Sheet be prvided that allws infrmatin t be prvided flexibly (similar t the secnd ptin abve). NEMMCO s preference is t retain the prpsal already in the Data Sheets (Optin 1), as there is a cncern that the generic sheets f Optin 2 might be ver-used. Optin 1 als allws NEMMCO t mnitr the apprpriateness f the Data Sheets ver time and, if necessary, adjust any Data Sheets that need t be updated. As the infrmatin prvided in the Data Sheets is cnfidential, Generatrs wuld nt be aware f the frm f infrmatin prvided by ther Generatrs that have similar technlgy, withut sme invlvement by NEMMCO. Therefre, a requirement fr apprval by NEMMCO wuld als allw the infrmatin t be prvided cnsistently, bth in terms f: the actual data requirements fr similar technlgies; and the level f detail prvided ver a range f technlgies. While Vestas cmment is nted, NEMMCO sees n reasn t change the requirements in the Data Sheets and the Mdel Guidelines in terms f the manner in which flexibility might be allwed. Page 16 f 71

17 5.5 Arrangement f Design and Setting Data Issue 5 Is there any better way in which the required separatin int Generating System Design Data Sheets and Generating System Setting Data Sheets culd be presented in the Data Sheets, while still preserving the Rule cncept f separate Data Sheets? Submissins: TransGrid: The prpsed methd f separating the Generating System Design Data Sheets, the Generating System Setting Data Sheets and the Generating System Setting Data Sheets appears t be satisfactry NEMMCO s cnsideratin and decisin N suggestins fr changing the frm f presentatin were submitted. NEMMCO sees n need t change the frm f presentatin. 5.6 Scpe f Studies fr which the Data Sheets are used Issue 6 Des this descriptin cver the cmplete range f study types fr which the Data Sheet infrmatin will be used (taking int accunt the purpses that must be cnsidered under S5.5.7)? Submissins: Suzln: Vltage fluctuatin (flicker) studies are nt currently cvered by the descriptins prvided. We als nte that Fault Calculatins are mentined in the initial bullet pints f page14, but have nt been discussed in the detailed text f page15. [Page references are t pages 14 and 15 f the Issues Paper.] TransGrid: The list f the types f studies seems t be cmprehensive NEMMCO s cnsideratin and decisin The Issues Paper listed a range f types f studies, including their descriptins, that might be required by NEMMCO and NSPs, fr which mdels might need t be prvided. Suzln suggests the need fr the inclusin f flicker studies and the need fr a mre thrugh descriptin f fault studies. NEMMCO acknwledges the need t perfrm flicker studies but understands that the mdel infrmatin specified in the Data Sheets prvides sufficient detail t assess the impact f flicker n the pwer system using cnventinal analytical methds. What might nt be included is the effect f flicker n pwer electrnic devices, hwever, this wuld prbably require electr-magnetic transient (EMT) analysis methds, fr which NEMMCO currently sees n need t require such mdels (see Sectin 5.24). It is reasnable t expect that shuld such studies be required, this shuld be the respnsibility f a Generatr (and the generating unit r generating system supplier). In relatin t the cmment regarding fault calculatins, this was cvered n page 15 f the Issues Paper: Data fr lad flws and fault calculatins are always required fr netwrk limit determinatin r assessment f perfrmance standards, NEMMCO sees n need t change the requirements in the Data Sheets and the Mdel Guidelines in terms f flicker and fault study requirements. Page 17 f 71

18 5.7 Impedance mdelling within a Generating system Issue 7 Mdelling f impedances within generating systems distributed acrss wide areas r cnnected by high impedances is necessary but in ther situatins (e.g. mst large synchrnus generating plant) these impedances are negligible fr ladflw analysis. What is an apprpriate way f requesting the impedance data that reflects these differences? Submissins: Suzln: Fr wind farms, reticulatin impedances shuld be included t a level that ensures accurate results. If the reticulatin impedances are very small, they can be neglected. The minimum impedance that needs t be mdelled depends n the particular case in questin, and shuld be at the mdeller s discretin. Raring 40s: It is suggested that infrmatin shuld nly need t be prvided if a participant is nt prviding a generating system mdel that includes these cmpnents NEMMCO s cnsideratin and decisin Bth submissins suggest that the internal generating system impedances need nly be supplied if the accuracy f the mdelling f the system is affected. This suggests that in sme cases, the data may be required. The Data Sheets already request branch impedance infrmatin t be included n single line diagrams. NEMMCO cnsiders that sme discretin culd be allwed, hwever, and will adjust the Data Sheets s that the branch impedance infrmatin is nly required where the branch impedance frm the grid interface t the furthest plant item in the generating system culd exceed 10% f the grid interface impedance. 5.8 Fault mdelling fr generatrs with pwer electrnic grid interfaces Issue 8 If the draft Data Sheet apprach will nt result in a measure f the fault current fr generating units that interface with the grid partly r whlly via pwer electrnics, what level f detail is required, r what mdel shuld be used? Submissins: Suzln: Detail f fault current limiters shuld als be required, including instantaneus amplitude versus time characteristic, and wavefrms. The time reslutin shuld be sufficient t define the characteristic. CitiPwer/Pwercr: This sectin refers t sub-transient reactive impedance f generating plant. This quantity is nt clearly defined fr asynchrnus generatrs. Pwercr suggests that the requirement be fr data crrespnding t fault currents as defined in AS TransGrid: TransGrid has n cmment n the mdel that shuld be used fr generating systems that are cnnected via pwer electrnics. Hwever, fr synchrnus generating systems, the requested shrt-circuit infeed data at the cnnectin pint in sectin f the Draft Data Sheets is very cnfusing fr the fllwing reasns: The Data Descriptin begins with Three phase shrt circuit infeed, which usually means the infeed frm the generatr fr a three-phase fault. Hwever, individual values are requested fr ther types f fault, e.g. line-line, line-line-grund, line-grund. If the intentin is fr Three phase shrt circuit infeed t mean the infeeds n the three phases fr the fllwing types f fault, then a change f wrding is required; The Data Descriptin suggests Symmetrical means 3 phase and Asymmetrical means ther types f fault. This is incrrect. The standards referenced define a symmetrical fault current t Page 18 f 71

19 have n dc ffset cmpnent and an asymmetrical fault current t cntain a dc ffset cmpnent, whether the fault is three phase r anther type f fault; and Fr fault types at the cnnectin pint ther than a three-phase fault, the infeed frm a generatr will depend n the sequence impedances that represent the rest f the netwrk. A Generatr will nt knw these netwrk impedances and hw they will vary ver time. Prvisin f the negative sequence and zer-sequence impedance f the generating system is sufficient fr the NSP r NEMMCO t calculate the generatr infeeds fr nn-three-phase faults at the cnnectin pint. The fllwing submissin was received during the Secnd Stage f the cnsultatin: Vestas: It is believed that the data requirements within the Data Sheet fr fault currents is sufficient and that n further mdels are required by Generatrs. NEMMCO states fault behaviur f generatin with pwer electrnic interfaces is nt yet cmpletely understd. NEMMCO has prpsed a peak making current and a RMS breaking current. This infrmatin may nt be knwn t the wind farm wner. The questin that arises is fr what purpse is this infrmatin valuable. NEMMCO has quted internatinal standard IEC60909-O:2001 is titled shrt circuit currents in three phase a.c. systems part 0: calculatin f current. This standard details the cases fr cnventinal equipment, and nt pwer electrnic equipment. Thusly, t assign values t the tw parameters peak making current and a RMS breaking current sme assumptins will need t be made. Subsequently, NEMMCO shuld be advised f the assumptins s that it can assess whether a particular simulatin study will be accurate r inaccurate NEMMCO s cnsideratin and decisin The submissins suggest that the data requested will nt always prvide the infrmatin that is required fr this analysis. The requirements in Sectin f the Data Sheets have been altered t crrect the references t symmetrical and asymmetrical faults. The language used is nw cnsistent with the definitins in AS NEMMCO acknwledges the cncern, shared by Suzln and CitiPwer/Pwercr, that the descriptin f impedances fr fault limited generating units des nt prvide the crrect fault current when the methds defined in AS are applied. In the absence f any directin frm the standard, NEMMCO has altered Sectin f the Data Sheets t include a requirement fr Generatrs (where the generating system fault respnse varies frm that expected by the standard) t prvide fault respnse traces fr faults simulated at the cnnectin pint f the generating system. These wavefrms are t be prvided fr each f the fault scenaris (single phase, three-phase and tw phase). This data is t be supplied at the maximum utput f the generating system (and any ther f generating system utput that culd lead t higher currents). In rder fr a Generatr t calculate the values required by Sectin f the Data Sheets, TransGrid rightly submits that there is a requirement fr a Generatr t be supplied with: (a) (b) Thevenin equivalent vltage and impedance fr the sequence netwrks (excluding the generating system) as seen frm the cnnectin pint; r the pre-existing, maximum shrt circuit current at the cnnectin pint and the vltage at which this ccurs. The Data Sheets have been revised t include this requirement and t specify the data received frm the NSP as a crss-check mechanism. NEMMCO maintains that this allws fr certainty in the calculatin f the generating system fault cntributin withut placing undue requirements n either the NSP r the Generatr. NEMMCO ntes Vestas cmment that the fault current infrmatin requested is sufficient and that mdels are nt required. NEMMCO agrees that this shuld be the case under nrmal Page 19 f 71

20 circumstances, hwever, in relatin t a mdel fr quasi steady state behaviur 2 in the Mdel Guidelines, instead f a Generatr being required t prvide a mdel in every case, the Generatr wuld nly be required t prvide further infrmatin n request by the NSP r NEMMCO. It is expected that this will be under unusual circumstances, as it is believed that the infrmatin requirements in the Data Sheets will cver the majrity f circumstances. In relatin t the questin raised by Vestas, the terms peak making current and RMS breaking current were terms used in the Issues Paper, althugh nt adpted in the Data Sheets r Mdel Guidelines. The Data Sheets use the terminlgy in the IEC standard. The fault current infrmatin (f the type described in the Data Sheets) is necessary fr bth the initial design f the cnnectin pint plant and fr assessing the impact at lcatins in the shared netwrk, where fault levels may be critical. In the lnger term, the infrmatin in the Data Sheets wuld be used t develp simple parameters t be used in ladflw-based prgrams fr lnger term cntinuus fault level assessments fr example, these types f assessments are used in cntingency analysis tls used in NSP and NEMMCO cntrl rms, t assess whether fault currents might be excessive, shuld a fault ccur. As mentined abve, the NSP r NEMMCO may need t carry ut a special investigatin and may require further infrmatin t incrprate int a mre sphisticated mdel. It was preferred that this latter infrmatin were nt specifically requested in the Data Sheets, as the requirement fr it is likely t be rare and may vary n a case-by-case basis. In relatin t Vestas cmment regarding the infrmatin requested in the Data Sheets, NEMMCO agrees that if any assumptins were used in the derivatin f the quantities, this infrmatin ught t be prvided as well. The Data Sheets will be adjusted accrdingly. It shuld be nted that a Generatr r Cnnectin Applicant may prvide the infrmatin in the frm f wavefrm infrmatin if the design r technlgy f the plant des nt allw accurate fault current infrmatin in the standard frm requested. 5.9 Frmat f Harmnic Infrmatin where an acceptable plant standard des nt exist Issue 9 In what frm shuld harmnic infrmatin be prvided by a Generatr, where an acceptable plant standard des nt exist? Is the harmnic characteristic impedance infrmatin available, r is a harmnic mdel fr harmnic resnance studies nrmally available? Submissins: Suzln: Data shuld be prvided in the frm defined by AS61400 Part 21. The characteristics and studies are nrmally available. Alstm: Harmnic infrmatin might nt be available frm a generatr until after the pst-cnnectin stage f develpment withut requiring extensive calculatins and studies. Generally where n specific requirements frm NSP are prvided, the standards AS/NZS r IEC are applicable. We believe that harmnic infrmatin (individual harmnics up t the 50th harmnic) measured after cnnectin t the grid (R2) wuld meet NSP's needs sufficiently. Raring 40s: A respnse will be prvided n this matter when a draft guideline is cmpleted. TransGrid: TransGrid has nly cme acrss a few generating systems that d nt have acceptable plant standards n harmnic generatin and is therefre unable t prvide suggestins n a standard frm f harmnic infrmatin exchange. In the near future, harmnic assessment f generating systems may be made in a cnsultative manner, with the generatr and TransGrid sharing generating system harmnic 2 See sectin f the Mdel Guidelines Page 20 f 71

21 impedances, generating system harmnic current surce levels, harmnic vltage cntributin limits, and transmissin system harmnic impedances. After a number f these assessments have been made, TransGrid wuld be in a better psitin t suggest standard frms f harmnic infrmatin exchange. The fllwing submissin was received during the Secnd Stage f the cnsultatin: Vestas: It is ften the case that pwer quality reprts, including harmnic testing, results are sufficient fr mdelling purpses. It is nt nrmally the case that harmnic mdels are required. It is questinable whether all the harmnics frm the 2nd t the 50th are necessary. Furthermre, NEMMCO shuld prvide details f the presumed mdel in rder fr parties ther than wind farm wners t understand what are the assumptins f the presumed mdel? Als, there may be perids f time that the harmnics have validity, and there are ther perids f time where the harmnics are nt applicable. Fr example, the switching f the pwer electrnic devices may ccur at 60MHz, and this may appear as a harmnic at the wind turbine, but the same harmnic may nt appear at the cnnectin pint. Hw will NEMMCO allw fr this in the data sheets? NEMMCO s cnsideratin and decisin There des nt appear t be a standard that specifies emissin limits fr harmnic injectin t the pwer system frm generating units fr any generating technlgy. The submissins recmmend tw standards: ne fr synchrnus generating units and ne fr wind generating units. Neither f these standards specify n-line harmnic emissin standards althugh AS specifies a Telephne Harmnic Factr. This is nt cnsidered relevant since it is an ff-line measurement and cannt be applied t asynchrnus generating units. In the absence f a standard, the requirements under Rule s must be satisfied by cmpliance with the limits specified by the relevant NSP. As Alstm pints ut, this is generally assessed after cnnectin, by measurement. Suzln indicates that there are standards that specify the measurement techniques that shuld be used t measure the harmnic perfrmance f the generating system. NEMMCO wuld expect that the NSP wuld require adherence t these standards r an agreed alternative apprach fr the prvisin f this data pst-cnnectin. As TransGrid submits, it is rare fr there t be unacceptable plant perfrmance with respect t harmnics and hence this pst-cnnectin apprach is apprpriate. There are n requirements fr harmnic infrmatin t be prvided in the Data Sheets. If an NSP requires infrmatin fr a specific study, this infrmatin wuld be sught separately, n a case-bycase basis Need fr additinal cmpnents in the Data Sheets Issue 10 D the cmpnents listed in the draft Data Sheets cver all cmpnents that need t be mdelled in rder t capture respnse t the types f pwer system disturbances listed abve, in the relevant timeframes? If nt, what is missing and fr what reasns? Submissins: Alstm: Statr resistance depends n temperature. Therefre, in the past indicated accurately in the data sheet statr resistance C and expanded the data sheet with rtr resistance C. The direct axis damper leakage time cnstant (TKD) is nt elabrated during type testing. This parameter may be used in rder t generate very detailed synch. machine mdels (Waltn, A., "THE DEVELOPMENT AND ANALYSIS OF EQUIVALENT CIRCUITS FOR SYNCHRONOUS MACHINES", University f QLD ). Hwever, this parameter wuld nt have any influence t the level f mdeling fr transient studies, where standardised mdels fr synch. machines are used. Page 21 f 71

22 TransGrid: The cmpnents listed in the draft Data Sheets cver all the cmpnents that need t be mdelled fr cnventinal generatrs. Limited experience with generatrs implementing new technlgies means that TransGrid is unable t suggest what cmpnents are missing fr these systems NEMMCO s cnsideratin and decisin Alstm suggests that rtr resistance (RF) be added t the Data Sheets and that the temperature at which rtr and statr resistances are determined shuld als be nted in the Data Sheets. NEMMCO has adjusted the Data Sheets t include rtr resistance and t require the specificatin f the relevant temperature (nrmal r typical temperature) at which the rtr and statr resistances apply. Alstm is cncerned that the direct axis leakage time cnstant (TKD) is nt elabrated during type testing. Further, the impact n mdelling accuracy f this parameter is questined. NEMMCO cnsiders that TKD is still required in the Data Sheets, as: damper winding effects are nrmally included in typical mdels fr synchrnus generatrs. It wuld nt appear t be applicable nly in very detailed mdels as, fr example, in the reference quted abve, TKD is an explicitly parameter in the peratinal equatins in the simple secnd rder and classical mdels. Als, a similar representatin is included in Reference [2], which recmmends such a mdel fr pwer system stability analyses; and this parameter is specifically required in sme mdel applicatins. A duplicated reference t TKD was included in the draft Data Sheets; it has been remved Data Sheet Cmpnent Suitability fr respnse t pwer system disturbance Issue 11 D the cmpnents listed in the draft Data Sheets cver all cmpnents that need t be mdelled in rder t capture respnse t the types f pwer system disturbances listed abve, in the relevant timeframes? If nt, what is missing and fr what reasns? Are there cmpnents fr which mdels have been requested in the draft Data Sheets that are unnecessary under all circumstances t capture respnse t the types f pwer system disturbances listed abve? Fr what reasns are they unnecessary? Are there better frmats fr prviding the data that are easier t prvide r mre suitable fr medium and lng term dynamic studies than what is described in the Data Sheets? Submissins: Suzln: We wuld nte that the text at the bttm f page19 the slwer vltage/reactive pwer cntrls implemented n wind farms des nt reflect wind farms which are being deplyed with mdern reactive plant e.g. STATCOM r DFIG cntrls Tw additinal categries shuld be added: STATCOM: duratin and level f permissible verlad, and the recvery perid fr cntinued nrmal service. Switched capacitrs: discharge time after being switched ut f service, prir t re-energisatin. These items are bth required as knwledge f availability f plant capabilities is required t achieve adequate mdelling accuracy. CitiPwer/Pwercr: Pwercr understands that the medium and lng term dynamic studies relate t verall system security eg fr trip f majr generatin, lad r intercnnectin. The dynamic mdels fr transient stability studies as currently prvided in respnse t S5.2.4 d nt generally apply fr these studies and mdels may need t be defined in detail. Page 22 f 71