Load flow studies are performed by utilities to ensure voltage levels and equipment currents stay within safe operating limits. They model the known loads, generator outputs, and voltage regulator set points to calculate voltages and currents throughout the system using methods like Gauss-Seidel or Newton-Raphson. These load flow studies help utilities maintain reliability by identifying any potential overloads or voltage violations.

1. LOAD FLOW STUDIES

2. Utilities Need to Know…….
 Voltage at all the Nodes in the System
Must be maintained within customers equipment operating limit
to prevent the damage to customer equipment .
To meet regulator requirements (Public Service /Utilities
Commission)
 Current Flows on all the equipment
I. Must be maintained within equipment operating limits
Load Flow Studies
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3. Load Flow Studies
Utilities Already Know…….
 Watt and VAR loads at all substations
I. Metering equipment monitors real time flow
 Generator Output Power
I. Based on capacity and Efficiency /Cast and Availability
 Voltages where voltage regulators maintains fixed voltage set
points
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GS Method For Load flow studies

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GS Method For Load flow studies
Solve for Pi and Qi

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diagonal elements
Off diagonal elements
GS Method For Load flow studies

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28. NR Method For Load flow studies
Quadratic Convergence
Less prone to divergence with ill conditioned problems
 Most Efficient and practical
Lesser Numbers of iterations