Power System Stability

Equal Area Criterion

Equal Area Criterion: Equal Area Criterion – In a system where one machine is swinging with respect to an infinite bus, it is possible to study transient stability by means of a simple Equal Area Criterion, without resorting to the numerical solution of a swing equation. Consider the swing equation If the system is unstable …

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Transient Stability in Power System

Transient Stability in Power System: Transient Stability in Power System – It has been shown already that the dynamics of a single synchronous machine connected to infinite bus bars is governed by the nonlinear differential equation where As said earlier, this equation is known as the swing equation. No closed format solution exists for swing …

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Single Machine Infinite Bus System

Single Machine Infinite Bus System: Figure 12.14 is the circuit model of a Single Machine Infinite Bus System through a line of reactance Xe. In this simple case From Eq. (12.29b) The dynamics of this system are described in Eq. (12.11) as Two Machine Infinite Bus System: The case of two finite machines connected through …

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Power Angle Equation

Power Angle Equation: Power Angle Equation – In solving the swing equation (Eq. (12.10)), certain simplifying assumptions are usually made. These are: Mechanical power input to the machine (Pm) remains constant during the period of electromechanical transient of interest. In other words, it means that the effect of the turbine governing loop is ignored being …

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Dynamics of Synchronous Machine

Dynamics of Synchronous Machine: Kinetic Energy of the Rotor at Dynamics of a Synchronous Machine is where But where where We shall define the inertia constant H such that where It immediately follows that M is also called the inertia constant. Taking G as base, the inertia constant in pu is The inertia constant H …

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