In order to prevent over voltages at light loads, it is necessary to have devices for absorbing reactive power (like shunt reactors) not only at either end of a long line but even at intermediate points. Generators connected at the ends of the line have limited reactive power absorption capability
Year: 2015
As the network becomes complex, application of Ohm’s law for solving the networks becomes tedious and hence time consuming. For solving such complex networks, we make use of Kirchhoff’s laws. Gustav Kirchhoff (1824-1887), an eminent German physicist, did a considerable amount of work on the principles governing the behaviour of
An active two-terminal element that supplies energy to a circuit is a source of energy. An ideal voltage source is a circuit element that maintains a prescribed voltage across the terminals regardless of the current flowing in those terminals. Similarly, an ideal current source is a circuit element that maintains
A SCADA System typically provides the following functions: • Comprehensive monitoring of primary and secondary plant • Secure control of primary plant • Supervision of secondary plant • Operator controlled display of non-SCADA data • Alarm management • Event logging • Sequence of events recording • Trend recording All functions
The slack or swing bus is usually a PV-bus with the largest capacity generator of the given system connected to it. The generator at the swing bus supplies the power difference between the “specified power into the system at the other buses” and the “total system output plus losses”. Thus
Each bus in the system has four variables: voltage magnitude, voltage angle, real power and reactive power. During the operation of the power system, each bus has two known variables and two unknowns. Generally, the bus must be classified as one of the following bus types: 1. SLACK OR SWING
GS method is very useful for very small systems. It is easily adoptable, it can be generalized and it is very efficient for systems having less number of buses. However, GS LFA fails to converge in systems with one or more of the features as under: • Systems having large number
Load flow studies are important in planning and designing future expansion of power systems. The study gives steady state solutions of the voltages at all the buses, for a particular load condition. Different steady state solutions can be obtained, for different operating conditions, to help in planning, design and operation
Electric circuit theorems are always beneficial to help find voltage and currents in multi loop circuits. These theorems use fundamental rules or formulas and basic equations of mathematics to analyze basic components of electrical or electronics parameters such as voltages, currents, resistance, and so on. These fundamental theorems include the
This theorem applies to networks containing linear bilateral elements and a single voltage source or a single current source. This theorem may be stated as follows: If a voltage source in branch A of a network causes a current of 1 branch B, then shifting the voltage source (but not
