Presentation Grid Reliability

8/6/2019 Presentation Grid Reliability

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PRESENTATION

ON

Grid Reliability Requirements, Stability andProtection

Presented by : Mr. M.Majumdar

Executive Director ( Commercial)WBSEDCL

10 th April , 2008


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Profile and Energy Scenario of West Bengal :

West Bengal is located in theeastern region of India with anarea of 87853 sq. km and 19districts. West Bengal shares

an international border withNepal, Bhutan and Bangladeshand is surrounded by IndianStates namely, Sikkim, Assam,

Orissa, Jharkhand and Bihar.Main languages spoken inWest Bengal are Bengali, Hindiand English. West Bengal ishaving a total population 80.22million (2001 Census) withdensity of population of 904 perSq.km.

WBSEDCL
http://powermap%2010%20pln%20cea.pdf/


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WBSDA

Some Basic Features :

Area 87853 SQ KMNo of Population 80.22 million

Urban Population 28.03 %

Total no of Mouzas 37910

No of Mouzas Electrified 34184

Peak Load : 4900 MW

Off-Peak Load : 3350 MW

Sundarban Mangrove Forest is not connected by Grid Power

Some Special Features about Electricity In West Bengal(as on March 31, 2008)

WBSEDCL


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WBSDA

WBSEDCL

List of Renewable & Co-generation plants selling power to

WBSEDCL :

Sl.No.

Name of theEntrepreneur

LocationType ofproject

Capacity(MW)

1. M/s Electro SteelHaldia, Dist

Purbo MedinipurCoke Oven

plant12.0

2.

M/s Neora Hydro

Ltd.

Neora, Dist

Darjeeling Hydel 3.0

3.M/s. Nippon

Power LimitedLodhama, Dist:

DarjeelingHydel 3.0

4. WBREDAMohan Dairy,Dist: Purulia

Bio-gas Plant 0.03


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WBSDA

WBSEDCL

List of Renewable & Co-generation plants who executed PPA

with WBSEDCL for sale of power:

Sl.No.

Name of theEntrepreneur

LocationType ofproject

Capacity(MW)

1.M/s. Kamarhatti

Co. Ltd.Raina,

Dist: BurdwanBio-mass 6.0

2

M/s. Amrit Bio-

Energy &Industries Ltd.

Bankati, Dist:Bankura Bio-mass 10.0

3.M/s. PCM Hydel

PowerCorporation Ltd.

Chel-I, DistDarjeeling

Hydel 6.0

4.M/s. Shyam

Energy LimitedChel-II, DistDarjeeling

Hydel 6.0

5.M/s. EasternHydro Power

Company Limited

Chel-III, Dist

DarjeelingHydel 4.2


6/19WBSEDCL

Some salient features of State Electricity Grid Code(SEGC):

Frequency variation : Rated frequency of the system 50 HZ.

and shall normally be controlled within

the bandwidth of 49 to 50.5 HZ

Voltage Variation : Shall not be more than Voltage rangespecified in IE Rules.

Sub-Station Equipment :All equipment shall be designed,manufactured, tested as per IEC /

BIS standard.

Each Connection between anagency and STS shall be controlled

by a circuit breaker capable of

interrupting at the connectionpoint.


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WBSEDCL

Protection systems are to be provided by all entities as

specified by STU.

Requires to isolate the faulty equipment and protect the

other equipments against all types of faults internal /

external within specified fault clearance time withreliability, selectivity and sensitivity.

Relay Setting Coordination shall be done by STU

STU shall arrange periodic meeting with the entities to

discuss coordination of protection.

Protection :


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WBSEDCL

A generating unit shall be capable of continuously supply its

normal rated active / reactive out put with specified systemfrequency and voltage variation.

Generating Unit shall be provided with an AVR, Protective

and safety devices. All Generating Units and associated Electrical Equipment

connected to State Grid shall be provided with adequate

protection so that State Grid does not suffer due to anydisturbances.

Each Generating Unit shall be fitted with a Turbine SpeedGovernor having an over all droop characteristic within therange of 3-6 % .

Each Generating Unit shall be capable of instantaneouslyincreasing out put by 5% limited to 105% MCR whenfrequency falls.

Requirements of Generating Unit:


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WBSEDCL

Every EHT line taking off from generating station or a sub-

station shall have distance protection and back up

protection.

For 132 KV lines three-zone non-switched distance

protection with suitable back-up protections to be used.

Transmission Line Requirements :


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WBSEDCL

All 33 KV and 11 KV lines at connection point shall beprovided with minimum of over current and earth fall

protection with or without directional features as.

Transformer requirements :

For transformers of HV class differential protectionshall be provided for 10 KVA and above.

For transformers of 2.5 MVA to less than 10 MVA timelag over current, earth fault and instantaneous REF

relays.All transformers of 2.5 MVA and above shall be provided

with gas operated relays, winding temperature and oil

temperature protection.

Distribution line requirements:


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WBSEDCL

Communication:

Communication system between grid sub-station

and generating station shall be developed by the

developer at their cost

Developers of co generation and renewable energy

sources shall abide by all applicable codes, rules &

regulations in regard to operational and

commercial practices


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WBSEDCL

Ownership and responsibility of maintaining and

testing of meter shall be mutually agreed

between the entities and the STU.

Minimum standard of accuracy of meter shall be

of class 0.2 or as specified by STU.

All CTs and PTs used for metering shall confirm

to the BIS or standard of IEC.

Metering :


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WBSEDCL

Procedure for connection to STS:

Any agency seeking connection to STS shall submit applicationon specified forms to STU along with the following details:

A report stating the purpose of connection, connection

point ,apparatus to be connected and beneficiaries ofconnection.

Prospective users shall, require to pay STU all chargesas specified by WBERC for conducting initial and anyadditional studies for processing the application.

Construction schedule and target completion date.

A confirmation to abide by the provisions of WBEGC,I.E rules and provisions of the regulation made by theCEA under the Act.

The connection point shall be at licensees gantry in case of CPP


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WBSEDCL

Connection Agreement:

A connection agreement shall include (but may not be limited

to), as appropriate, within its terms and conditions, the

following: A condition requiring both parties to comply with

WBEGC and Grid Code;

The details of connection, technical requirements and

commercial arrangements;

The details of any capital expenditure arising from

necessary reinforcement or extension of the system and

demarcation of the same between the concerned parties;


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WBSEDCL

Connection Agreement: contd..

A Site Responsibility Schedule;

The metering arrangements;

The general procedure, guidelines, etc. on protection and

telemetry;

The procedures necessary for site access, site operationalactivities and maintenance standard for equipment of

Licensee at the premises of the User and vice-versa;


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The Cogeneration and renewable energy sourcesexcepting roof-top Solar PV and Bio gas sources

shall be connected to state grid at a voltage of 33KV or 11 KV subject to technical suitability

Delivery point shall be the nearest grid sub stationof 33/11 KV voltage level

Roof top solar PV system shall be connected at LVor MV or 11 KV

Bio gas plant shall be connected at MV or at 11KV

Connectivity for Co-generation & Renewable

sources as per WBERC regulation:

WBSEDCL


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WBSEDCL

Procedure to be followed for Co-generation & Renewable

Energy Sources:

After preliminary discussions with the buyer licensee, the

developer shall submit full details of the projects alongwith

cost data and financial charges and tariff for direct sale tothe licensee.

The buyer licensee shall examine the tariff proposal in the

light of price reasonableness, impact on consumer tariffand the price cap specified in these regulations.


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WBSEDCL

Procedure to be followed for Co-generation & Renewable

Energy Sources:

MOU / PPA shall be signed between developer and

purchaser. In case of open access, the transmission

and/orwheeling agency shall also be a party to the MOU /PPA. In the MOU / PPA with details of connectivity,

completion of project and commencement of supply,

periods of supply (month wise), time of supply (peak / off

peak), technical & commercial obligation, security and

modes of payment of each party, etc. in line with these

regulations shall be suitably incorporated. The MOU /

PPA, as agreed and signed, shall be submitted to the

Commission.


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WBSEDCL

Documents

Presentation Grid Reliability