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STATIC SHUNT COMPENSATION

Presented by

T.S.L.V.Ayyarao

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OBJECTIVES OF SHUNT COMPENSATION

Steady-state transmittable power can be increased. Voltage profile can be controlled. Shunt connected reactors (fixed or mechanically

switched) are applied to minimize line over voltage under light load conditions.

Shunt connected capacitors are applied to maintain voltage levels under heavy load conditions.

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MIDPOINT REGULATION FOR LINE SEGMENTATION

Consider two bus transmission model with ideal var compensator at the midpoint.

The compensator divides line into 2 parts.

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MIDPOINT REGULATION FOR LINE SEGMENTATION

Midpoint var compensator exchange only reactive power with the line.

Real power is same at each terminal

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MIDPOINT REGULATION FOR LINE SEGMENTATION

The transmitted power is

The relation between P, Q and angle

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MIDPOINT REGULATION FOR LINE SEGMENTATION

Midpoint shunt compensation significantly increase the transmittable power.

Mid point of the transmission line is the best location for the compensator.

Voltage sag is maximum at the mid point.

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END OF LINE VOLTAGE SUPPORT TO PREVENT VOLTAGE INSTABILITY

Consider a radial Transmission line

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END OF LINE VOLTAGE SUPPORT TO PREVENT VOLTAGE INSTABILITY

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END OF LINE VOLTAGE SUPPORT TO PREVENT VOLTAGE INSTABILITY

Reactive shunt compensation can effectively increase the voltage stability limit and regulates the terminal voltage.

End of the line is the best location for compensator.

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IMPROVEMENT OF TRANSIENT STABILITY

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IMPROVEMENT OF TRANSIENT STABILITY

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IMPROVEMENT OF TRANSIENT STABILITY

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POWER OSCILLATION DAMPING