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Presentation of ENTSO-e Draft Connection Codes

Requirements for Generators & Requirements for Distribution Network Companies and Demand Facilities

Jonathan Sprooten February 21, 2012 1


Agenda • •

Framework and process of the NC on connection Scope of the Network Codes

Network Code Requirements for Generators • Categorization • Graded approach of the requirements and Examples of requirements • Compliance and notification procedure

Network Code on Demand Connection • Scope of the DCC • Important New definitions • Examples of requirements • Compliance and notification procedure

23/02/2012

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Network Codes: framework and process Request f or draf ting FWGL EC

Development of FWGL

On a topic identified in art.8 (6) of Regulation EC 714/2009

Develop FWGL (6 month period) ACER

In consultation with ENTSO-E, stakeholders, with input from Ad-Hoc Expert Group

Request f or draf ting NC EC

According to FWGL submitted by ACER

Develop NC (12 month period) ENTSO-E

Development of NC

In consultation with stakeholders according to FWGL

Assessment of NC ACER

Recommendation of NC to EC

Comitology (where appropriate) EC

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In consultation with all stakeholders resulting in legally binding NC

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Network Codes: framework and process Requirements for generators Dec ’10

Framework Guidelines on Network Connections draft

Mar ’11

First public draft and informal public consultation

20/7/11

Framework Guidelines on Network Connections final version

29/7/11

Letter EC to start procedure

Dec’11

Letter EC to start procedure

Nov/Dec ‘11

Informal communication with stakeholders

31/12/11

First Draft Completed

12/01/12 – 26/01/12

Internal Consultation

Draft approval by ENTSO-e

13/03/12

Draft approval by ENTSO-e

24/01/12 – Start of Public Consultation 20/03/12

April/May 12

Start of Public Consultation

30/05/12

25/10/12

Final draft approval by ENTSO-e

27/10/11

13/11/11

Demand Connection Code

Second Draft completed

Final draft approval by ENTSO-e

Network Code should be applied within 3 years following its publication 23/02/2012

4


Agenda • •

Framework and process of the NC on connection Scope of the Network Codes

Network Code Requirements for Generators • Categorization • Graded approach of the requirements and Examples of requirements • Compliance and notification procedure

Network Code on Demand Connection • Scope of the DCC • Important New definitions • Examples of requirements • Compliance and notification procedure

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Scope of the Network Codes: « cross-border » network issues EC Regulation 714/2009 Article 8 (7) defines that “the network codes shall be developed for cross-border network issues and market integration issues and shall be without prejudice to the Member States’ right to establish national network codes which do not affect cross-border trade”. The term “cross-border network issue” itself is not defined by this EC Regulation. Targets of the EC 3rd legislative package for the internal electricity market, are: • Supporting the completion and functioning of the internal market in electricity and cross-border trade • Facilitating the targets for penetration of renewable generation • Maintaining security of supply Choice of the Drafting Team (DT) All requirements that contribute to maintaining, preserving and restoring system security in order to facilitate proper functioning of the internal electricity market shall be regarded as “cross-border network issues”. 23/02/2012

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Scope of the Network Codes: Technical ability of the units / Operational requirements / Participation to paid-for services •

Requirements = technical ability of the generating units • with a long-term view towards system needs (no change required in the near future that could have been anticipated) • = Connection Requirements

Operational requirements given by the relevant Network Operator might differ, but they need to be within the range of the Network Code. • Example: units must be able to withstand a df/dt of 2 Hz/s, but it is common practice in LV/MV Networks to request a ROCOF relay set to 0,5 Hz/s (antiislanding protections)

• •

The participation to and remuneration for ancillary services are not in scope. The financial incitation for low reactive energy of demand units is not in the scope. • Is it beneficial for the final user to impose technical abilities for ancillary services or to let the market decide whether to invest or not? • Position paper in preparation by the WG Ancillaries of the Market Committee, this highlight some market failures

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What is a Significant Grid User?

ACER Framework Guideline on Electricity Grid Connection “The network code(s) developed according to these Framework Guidelines shall define appropriate minimum standards and requirements applicable to all significant grid users.” “The minimum standards and requirements shall be defined for each type of significant grid user and shall take into account the voltage level at the grid user’s connection point. The network code(s) shall specify the criteria and methodology for the definition of significant grid users. These shall be based on a predefined set of parameters which measure the degree of their impact on cross-border system performance via influence on control area`s security of supply, including provision of ancillary services ("significance test")…”

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Agenda • •

Framework and process of the NC on connection Scope of the Network Codes

Network Code Requirements for Generators • Categorization • Graded approach of the requirements and Examples of requirements • Compliance and notification procedure

Network Code on Demand Connection • Scope of the DCC • Important New definitions • Examples of requirements • Compliance and notification procedure

23/02/2012

9


Network Code Requirements for Generators: Documentation & references •

ENTSO-e Draft « Requirements for grid connection applicable to all Generators » • 27/10/2011 • Pilot code (Abbreviation = NC RfG) • Meant to become a EU Regulation • Contrarily to the RG CE Operation Handbook, there is no appendix with the background for the establishment of the code

Frequency Asked Questions • 23/11/2011 • 25 FAQs

Draft « Motivation and Approach » • 30/11/2011 • Position paper

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Categorization: Criteria for categorization (1) •

By « technology »:

+ take into account specificities of either the primary source of energy and / or the connection technology to make the best use of the inner capabilities without excluding any particular technology = equitable treatment of all generators • primary source  issue for access and paid-for ancillary services: out of scope • technology of the connection  has a large influence on the capability • DT: Synchronously connected or not synchronously connected (= through a power electronic interface) • Asynchronous generators and DFIG are synchronously connected •

By size of the unit (MW or MVA thresholds ):

+ investment in advanced technical abilities provides a better cost/benefit ratio for larger units.

+ for the system operator, there is also an impact of size on the system security. - the average size of units may change with the power generation mix 23/02/2012

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Categorization: Criteria for categorization (2) •

By voltage level at the Connection Point (CP)

- Not ideal because the operator is entitled to impose a V-level according to the size of the unit. This might be based on short-circuit power (strength of the system) and the admissible emission level (power quality).

- how to handle small units installed by industrial load at high voltage ? - V-level specificities: earthing & protection philosophy, electrical distances & geographical impact of a disturbance  very different across EU • DT: differentiate units at VHV (≥ 110 kV)

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Categorization: Choice of the DT • • • •

Type A : CP < 110 kV and Maximum Capacity is >= 400 W Type B : CP < 110 kV and Maximum Capacity >= 1 MW (*) Type C : CP < 110 kV and Maximum Capacity >= 50 MW (*) Type D : CP >= 110 kV OR Maximum Capacity >= 75 MW (*) (*) these power thresholds can be set lower but not higher by the TSO

General requirements for all types of generation units

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Synchronous

Power Park Modules

Offshore

Requirements for Synchronously connected units

Requirements for Non synchronously connected units

Requirements for offshore connected units

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Categorization: Choice of the DT •

How to handle small units installed by industrial load at high voltage ? • Massive derogation

Why a specific category for offshore? • Definition: Offshore PPM = PPM having a Connection Point located offshore • A PPM having a Connection Point located onshore falls in the onshore category  all Belgian offshore wind • Various configurations are considered (AC single CP, meshed AC, DC, hybrid, etc) • Not all requirements apply to offshore and depends on the configuration

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Agenda • •

Framework and process of the NC on connection Scope of the Network Codes

Network Code Requirements for Generators • Categorization • Graded approach of the requirements and Examples of requirements • Compliance and notification procedure

Network Code on Demand Connection • Scope of the DCC • Important New definitions • Examples of requirements • Compliance and notification procedure

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Graded Approach •

Generator capabilities are formulated from a system performance perspective, independent from technology

Need to be able to cope with evolutions in generation mix

Significance is regarded per requirement Europe wide balancing services Refined and controllable dynamic response

Type D Type C Type B

Automated response, operator control, information Common failure mode for all plants (frequency)

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Type A

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General Requirements Title FREQUENCY RANGES LIMITED FREQUENCY SENSITIVE MODE (OVERFREQUENCY) RATE OF CHANGE OF FREQUENCY WITHSTAND CAPABILITY REMOTE SWITCH ON/OFF CONTROL SCHEMES AND SETTINGS INFORMATION EXCHANGE CAPABILITY OF RECONNECTION AFTER AN INCIDENTAL DISCONNECTION DUE TO A NETWORK DISTURBANCE POWER/VOLTAGE QUALITY SYNCHRONISATION ACTIVE POWER CONTROLLABILITY AND CONTROL RANGE DISCONNECTION DUE TO UNDERFREQUENCY FREQUENCY RESTORATION CONTROL FREQUENCY SENSITIVE MODE LIMITED FREQUENCY SENSITIVE MODE (UNDERFREQUENCY) MONITORING OF FREQUENCY RESPONSE LOSS OF STABILITY RATE OF CHANGE OF ACTIVE POWER SIMULATION MODELS STEADY-STATE STABILITY BLACK START CAPABILITY TO TAKE PART IN ISOLATED NETWORK OPERATION QUICK RE-SYNCHRONISATION RECONNECTION AFTER TRIPPING ONTO AUXILIARY SUPPLY SHORT CIRCUIT CONTRIBUTION HIGH/LOW VOLTAGE DISCONNECTION VOLTAGE RANGES …. 23/02/2012

Requirement type Frequency stability Frequency stability Frequency stability Frequency stability System management System management System restoration System management System management Frequency stability Frequency stability Frequency stability Frequency stability Frequency stability Frequency stability System management System management System management Robustness of Generating Units System restoration System restoration System restoration System restoration Voltage stability Voltage stability Voltage stability ….

Type A Type B Type C Type D X X X X X X X X X X X X X X X X X X X X X

X

X

X X X X X X X X X X X

X X X X X X X X X X X

X

X

X X X X X X

X X X X X X ….

… 17


Specific Requirements for Synchronously Connected Units Title POST FAULT ACTIVE POWER RECOVERY

Requirement type Robustness of Generating Units

FAULT RIDE THROUGH CAPABILITY OF SYNCHRONOUS GENERATORS CONNECTED BELOW 110 kV

Robustness of Generating Units

REACTIVE POWER CAPABILITY (SIMPLE) VOLTAGE CONTROL SYSTEM (SIMPLE) CONSTANT OUTPUT AT TARGET ACTIVE POWER

Voltage stability Voltage stability Frequency stability

MAXIMUM POWER REDUCTION AT UNDERFREQUENCY COORDINATION OF SPEED AND POWER CONTROL OF SYNCHRONOUS GENERATING UNITS

Type A

Type B

Type C

Type D

X

X

X

X

X

X X X

X

Frequency stability

X

X

System management

X

X

X

X

X

X

X X

X X X X X

REACTIVE POWER CAPABILITY AT MAXIMUM ACTIVE Voltage stability POWER REACTIVE POWER CAPABILITY BELOW MAXIMUM ACTIVE Voltage stability POWER STEADY STATE VOLTAGE CONTROL Voltage stability TRANSIENT VOLTAGE CONTROL Voltage stability EXCITER SPECIFICATION Voltage stability STATOR CURRENT LIMITER Voltage stability VOLTAGE CONTROL SYSTEM Voltage stability FAULT RIDE THROUGH CAPABILITY OF SYNCHRONOUS GENERATORS CONNECTED AT 110 kV OR ABOVE

Robustness of Generating Units

X

POWER OSCILLATIONS DAMPING CONTROL POWER SYSTEM STABILIZER

Voltage stability Voltage stability

X X

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Specific Requirements for Power Park Modules Title REACTIVE POWER CAPABILITY (SIMPLE)

Requirement type Voltage stability Robustness of Generating POST FAULT ACTIVE POWER RECOVERY Units REACTIVE CURRENT INJECTION Voltage stability FAULT RIDE THROUGH CAPABILITY OF POWER Robustness of Generating PARK MODULES CONNECTED BELOW 110 kV Units SYNTHETIC INERTIAL CAPABILITY Frequency stability PRIORITY TO ACTIVE OR REACTIVE POWER Voltage stability CONTRIBUTION REACTIVE POWER CAPABILITY AT MAXIMUM Voltage stability ACTIVE POWER REACTIVE POWER CAPABILITY BELOW Voltage stability MAXIMUM ACTIVE POWER REACTIVE POWER CONTROL MODES Voltage stability FAULT RIDE THROUGH CAPABILITY OF POWER Robustness of Generating PARK MODULES CONNECTED AT 110 kV OR Units ABOVE

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Type A X

Type B X

Type C

Type D

X

X

X

X

X

X

X

X X

X

X

X

X

X

X

X

X

X X

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Agenda • •

Framework and process of the NC on connection Scope of the Network Codes

Network Code Requirements for Generators • Categorization • Graded approach of the requirements and Examples of requirements • Compliance and notification procedure

Network Code on Demand Connection • Scope of the DCC • Important New definitions • Examples of requirements • Compliance and notification procedure

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Structure of the Network Code

General provisions

Requirements

Operational Notification Procedure for Connection

Compliance

Derogations

Final Provisions

Entry into force and application of the Network Code

Definitions

General requirements

New generating units

Compliance monitoring

Request

Scope

Synchronous Generating Units

Existing generating units

Compliance testing

Decisions

Power Park modules

Compliance simulations

Offshore Power Park modules

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Compliance & Operational notification procedure : New units -

Itemized compliance statement

-

Detailed technical data

-

Manufacturer data & performance certificate

-

Simulation models Interim operational notification

-

Practical tests demonstrating compliance

-

Validation of simulation tests and studies Final operational notification

-

Modification or loss of capacility

-

Equipment failure Limited operational notification

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Compliance & Operational notification procedure: Derogations For both new and existing units • •

Generator • introduces request for derogation to the TSO (Incl. Detailed reasoning) TSO • can request an exemption from CBA to the National Regulator • provide the National Regulator with his assessment, possibly based on CBA National Regulator • informs the generator, TSO and ACER about the decision

International coordination •

National Regulator • keeps a register of derogations granted or rejected • Sends un update to ACER every 6 months ACER can emit an advise to National Regulators

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Agenda • •

Framework and process of the NC on connection Scope of the Network Codes

Network Code Requirements for Generators • Categorization • Graded approach of the requirements and Examples of requirements • Compliance and notification procedure

Network Code on Demand Connection • Scope of the DCC • Important New definitions • Examples of requirements • Compliance and notification procedure

23/02/2012

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ENTSO-e Demand Connection Code: Documentation & references •

ENTSO-e Draft « Demand Connection Code » • 20/12/2011 • Abbreviation = NC DCC • Meant to become a EU Regulation • Contrarily to the RG CE Operation Handbook, there is no appendix with the background for the establishment of the code

Drafting Team Working Draft « Demand Connection Code » • 07/02/2012

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Scope of DCC • Code Applicable for • Some requirements for All (significant and non significant) Demand Facilities • Significant Demand Facilities • Some requirements for All All Distribution Networks • Transmission connected Distribution Networks

• Retroactive applications of requirements for Existing Demand Facilities/ or Existing Connected Distribution Networks 1. TSO shall carry out a • Quantitative cost-benefit analysis (socio-economic, internal market and crossborder trade benefits, integration of renewables) • Proposal including an operational notification procedure and an appropriate transition period for implementing the requirements. • Public Consultation 2. National Regulatory Authority takes decision

• Principle of superposition: In situations where generation and demand co‐exists • All demand requirements within this code will be evaluated on the basis that the generation is not present. • The generation facility will have to comply with the requirements of the Network Code Requirements for Generators 23/02/2012

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Agenda • •

Framework and process of the NC on connection Scope of the Network Codes

Network Code Requirements for Generators • Categorization • Graded approach of the requirements and Examples of requirements • Compliance and notification procedure

Network Code on Demand Connection • Scope of the DCC • Important New definitions • Examples of requirements • Compliance and notification procedure

23/02/2012

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Some Important Definitions (1/2) • Connection Point ‐ is the location at which - the Demand Facility is connected to a network - the Distribution Network is connected to a Transmission Network. • Demand Unit ‐ a Demand Unit is an indivisible set of installations which can be actively controlled by a Demand Facility Operator to moderate its electrical energy demand. (…) • Significant Demand Facility – Demand Facility which has the ability either singularly or when considered aggregated to impact on the cross‐border system performance via influence on the control area’s security of supply. For the purposes of this network code this will be either a Transmission Connected Demand Facility or a Demand Facility with Demand Side Response, unless explicitly stated otherwise within the Network Code. • Closed Distribution Network – A system (network) which distributes electricity within a geographically confined industrial, commercial or shared services site and does not (…) supply household customers. 23/02/2012

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Some Important Definitions(2/2) • Distribution Network – is an electrical system for the distribution of electrical power from and to third party[s] connected to it, a transmission or another distribution network, including Closed Distribution Networks. • Distribution System Operator (DSO) ‐ An Regulated Distribution Network Operator (electricity) of Distribution Network assets. • Transmission Network ‐ is an electrical Network for the Transmission of electrical power from and to third party[s] connected to it, including Demand Facilities, Distribution Networks or other Transmission Networks. This extent of this Network is defined at a national level. • Demand Side Response (DSR) - Demand offered for the purposes of but not restricted to providing Active or Reactive Power management, Voltage and frequency regulation and System Reserve. • Demand Aggregation – is a set of Demand Facilities which can be operated as a single facility for the purposes of offering one or more Demand Side Response services. 23/02/2012

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Agenda • •

Framework and process of the NC on connection Scope of the Network Codes

Network Code Requirements for Generators • Categorization • Graded approach of the requirements and Examples of requirements • Compliance and notification procedure

Network Code on Demand Connection • Scope of the DCC • Important New definitions • Examples of requirements • Compliance and notification procedure

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23/02/2012

X

X

X

Transmission Connected Distribution Networks above 110kV

Transmission Connected Distribution Networks

Closed Distribution Networks

Significant Demand Facility above 110kV

X

All Distribution Networks

X

Significant Demand Facility

Temperature Controlled Demand Facility

Title FREQUENCY RANGES VOLTAGE RANGES SHORT-CIRCUIT REQUIREMENTS REACTIVE POWER REQUIREMENTS PROTECTION AND CONTROL LOW FREQUENCY DEMAND DISCONNECTION DSR - ACTIVE POWER CONTROL DSR - REACTIVE POWER CONTROL DSR - TRANSMISSION CONSTRAINT MANAGEMENT DSR - SYSTEM FREQUENCY CONTROL POWER QUALITY SIMULATION MODELS

All Demand Facilities

General Requirements

X

X

X

X X

X X X

X

(X)

(X)

(X)

(X)

(X)

(X)

(X) X X

(X) X X 31


Example: Short-Circuit Requirements • The Relevant Network Operator shall define the maximum value of short‐circuit Current that the Demand Facility and Distribution Network must be able to support. • The Relevant TSO shall have the right to request information from the DSO, concerning the contribution in terms of short‐circuit current of Generation Units connected to the Distribution Network.

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Example: Reactive Power requirements (1/2) • Is Defined in FWGL ACER Section 2.1

• Reactive power should be generated were needed : Quick CBA of reactive power equipment on different voltage levels: More cost effective at lower voltage levels

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Example: Reactive Power requirements (2/2) • Defined in power (not energy) at the Connection Point  Not present in Belgian RT/TR,  Cost penalty defined in reactive energy over 15min  No maximum value for reactive power (or power factor)  For Significant Demand Facilities  Without onsite generation 0.95 (ind)<Cos(phi)<1  With onsite generation 0.9 (ind)<Cos(phi)<0.9(cap)  For Transmission Connected Distribution Networks, (DSO and Closed Distribution Systems)  0.9 (ind)<Cos(phi)<0.9(cap)  Capability to maintain 0MVAr exchange at nominal Voltage with a deadband of 5% of active power for a load exchange of no higher than 25% of the Maximum Import Capacity  TSO can request capability to maintain 0MVAr exchange at nominal Voltage average (within deadband of 5% of active power over the same period) for no longer than 1h for a specified range of active power exchange 23/02/2012

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Example : Demand Disconnection/Island Mode for System Defense and Demand Reconnection (1/2) • With regard to Low Frequency Demand Disconnection devices: •

For Distribution Network and Transmission connected Demand Facilities

Low Frequency (or alternatively if specified by the TSO, ROCOF) Disconnection of a percentage of demand to be specified by the TSO

Relays should monitor direction of active power flow

• With regard to Low Voltage Demand Disconnection devices (including OLTC blocking)

Based on the TSO assessment

Relays should monitor direction of active power flowµ Significant Demand Facilities and Transmission Connected Distribution Networks shall fulfill the following requirement referring to reconnection of a Demand Facility or Transmission Connected Distribution Network:

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Example : Disconnection/Island Mode (2/2)

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Example : Demand Response Requirements (1/3) • Framework Guidelines Grid Connection July 2011 Section 2.1.2 The network code(s) shall set out necessary minimum standards and requirements to be followed when connecting a consumption unit to the grid, to enable demand response and/or participation of consumption units in other grid services, on a contractually-agreed basis.’

• On Voluntary basis •

With regard to Demand Side Response Active Power Control and Reactive Power Control and Transmission Constraint Management

For Demand Facilities and Closed Distribution Network Operator

• On Mandatory basis •

With regard to Low Frequency Demand Response

For temperature controlled devices (for example, fridges, freezers, heat pumps, immersion heaters)

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Example : Demand Response Requirements (2/3) • Demand Side Response Active Power Control, Reactive Power Control, Transmission Constraint Management •

TSO shall have the right to specify the network location, usage and/or scale

One of the three methods:

Modify demand usage ordered by command sent by NO

Modify demand usage with frequency and/or voltage control and pre‐alert signal sent by NO.

For Voltage control, Disconnection/reconnection of static compensation facilities controlled by NO.

The Demand Facility or Closed Distribution System shall be able to stay connected to the network due to ROCOF up to 2Hz/s.

• Very fast Frequency Response - (i.e. Inertia/synthetic inertia) – if Any • Demand Side Response System Frequency Control •

For temperature controlled devices

Device regulates between two sets points - stored energy between the points can be used to increase or reduce these devices effective demand

Deadband of frequency defined by TSO of the synchronous area

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Demand Response

Temperature Frequency Target

Example : Demand Response Requirements (3/3)

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Example: Simulation Models • The models shall show the behavior of the Significant Demand Facility and/or Transmission connected Distribution Network in both •

Steady‐state simulations

Dynamic simulations (long term, short term, and electromagnetic transient) at the Connection Point

• For the purpose of dynamic simulations, the model provided shall contain the following sub-models: • Power control; • Voltage control; • Demand Facility and Transmission connected Distribution Network protection models • The constituent demand types, i.e. Industrial, Commercial, Domestic; and • Converter models as applicable.

• The Relevant Network Operator or Relevant TSO shall have the right to require Significant Demand Facility and/or Transmission Distribution Network recordings in order to compare the response of the model with these recordings 23/02/2012

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Agenda • •

Framework and process of the NC on connection Scope of the Network Codes

Network Code Requirements for Generators • Categorization • Graded approach of the requirements and Examples of requirements • Compliance and notification procedure

Network Code on Demand Connection • Scope of the DCC • Important New definitions • Examples of requirements • Compliance and notification procedure

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Compliance & Operational notification procedure : -

Itemized compliance statement

-

Detailed technical data

-

Manufacturer Data & Performance Type Certificate (Report containing results from laboratory type testing for temperature control devices)

-

Simulation models (static and dynamic) Interim operational notification

For Significant Demand Facilities and Transmission-connected Distribution Networks only -

Practical tests demonstrating compliance

-

Validation of simulation tests and studies Final operational notification

-

Modification or loss of capacility

-

Equipment failure Limited operational notification

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Compliance & Operational notification procedure : Derogations For both new and existing Demand Facilities and Distribution Networks • •

Demand Facility and Distribution Networks • introduces request for derogation to the TSO (Incl. Detailed reasoning) TSO • can request an exemption from CBA to the National Regulator • provides the National Regulator with his assessment, possibly based on CBA National Regulator • informs the Demand Facility and DSO, TSO and ACER about the decision

International coordination •

National Regulator • keeps a register of derogations granted or rejected • sends an update to ACER and ENTSO-e every 6 months

ACER • emits advises to National Regulators

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Presentation of ENTSO-e Draft Connection Codes

Requirements for Generators & Requirements for Distribution Network Companies and Demand Facilities

Jonathan Sprooten February 21, 2012 44


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