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Power Control Systems in Pakistan

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System Operation

• Generation Control• Switching & Operating Control

of 500 & 220 kV Network

Switching & Operating Control of 132 & 66 kV Southern Network

RCCS(Regional Control Centre South)

Jamshoro

Switching & Operating Control of 132 & 66 kV Northern Network

RCCN(Regional Control Centre North)

Islamabad

NCC(National Control Centre)

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HOW NPCC OPERATES?

Criteria to Check System Stability?

1) Frequency Limits (49.5 to 50.5 Hz)

2) Voltage (±10%)

3) Switching (500kV, 220kV Switchgears)

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VOLTAGE CONTROL

● MVARs SHARING OF POWER STATIONS

● SWITCHING OF CAPACITORS/REACTORS

● TAP CHANGING OF 500/220KV & 220/132KV

TRANSFORMERS.

5

● Automatic Generation Control, AGC

(Limited only to 03 Units of Tarbella P/S )

● Telephone Messages to various Power Stations to

Raise/Lower the Set-points

FREQUENCY CONTROL

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NPCC Operators’ Duties also include

●LOAD FORECASTING (through Syrup Software)

● UNIT COMMITMENT

● ECONOMIC DESPATCH

MANUALLY CONTROLLED PARAMETERSAT NPCC ISLAMABAD

PARAMTERS1. DEVICE SWITCHING (e.g., C.Bs & Isolators)

2. OPERATION OF OLTC (ON-Load Tap Changer)

3. LOAD FORECAST

4. HYDROLOGY (According to Indent of

IRSA)

CONSTRAINTS1. Old & Deteriorated Devices

2. Deteriorated Tap Changers

3. Acute power Shortage

4. Required Advance Technology

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8

SCADA MONITORING & CONTROLAT NPCC ISLAMABAD

ON LINE MONITORING OF POWER FLOW

(LOADING OF T/Ls, T/Fs & P/S)

STATUS OF EQUIPMENTS (C.Bs, ISOLATORs)

AGC (Automatic Generation Control)

(Limited to 03 Units of Tarbella P/S)

RELAY INDICATIONS

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10

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Four (4) Thermal Power Generation Companies (GENCOs)

1. Southern Generation Power Company Limited (GENCO-1) head quarter at Jamshoro district Dadu near Hyderabad Sindh.

2. Central Power Generation Company Limited (GENCO-2) head quarter at Guddu district Jacobabad Sindh.

3. Northern Power Generation Company Limited (GENCO-3) head quarters at TPS Muzaffargarh district Muzaffargarh Punjab.

4. Lakhra Power Generation Company Limited (GENCO-4) Headquarter at WAPDA House Lahore.

THERMAL GENERATION

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One (1) National Transmission & Power Dispatch Company (NTDC)

Nine (9) Distribution Companies (DISCOs) as under: 1. Lahore Electric Supply Company (LESCO) 2. Gujranwala Electric Power Company (GEPCO) 3. Faisalabad Electric Supply Company (FESCO) 4. Islamabad Electric Supply Company (IESCO) 5. Multan Electric Power Company (MEPCO) 6. Peshawar Electric Power Company (PESCO) 7. Hyderabad Electric Supply Company (HESCO) 8. Quetta Electric Supply Company (QESCO) 9. Tribal Electric Supply Company (TESCO)

TRANSMISSION and DISTRIBUTION

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Source: Pakistan Energy Book 2008