Sumários
Single phase fault by symmetrical components
15 novembro 2012, 11:00 • Luis Marcelino Ferreira
Review of concepts of balanced and symmetrical systems. Unsymmetrical and unbalanced systems.
Single phase faults by using symmetrical components
Derivation of short-circuit current
Diagram coupling the three systems in series
Computation of system currents and system voltages
Maximum value for single-phase short circuit as compared to three phase’s
Voltage values for non faulted phases
Two additional power flow problems
13 novembro 2012, 11:00 • Luis Marcelino Ferreira
Review of the resolution of book problems as a recommend practice
A problem for radial power flow
Computation of currents for the first iteration: example
For the same example, computation of node voltages for the first iteration
A second problem: a two-bus power flow problem in which the load is P=f(V) and Q=g(V)
Cases for f and g polynomial and exponentials
Review of Prob 6.6: elasticity 0, 1 and 2
Resolution in polar coord and in rectangular coord
Surprising simplicity of using rectangular coord
Discussion of the results in terms of the severity of angles and flow wrt elasticities
Single phase fault by direct analysis
13 novembro 2012, 09:30 • Luis Marcelino Ferreira
Three phase (ABC) analysis without tranforms
Circuit analysis
Coupling impedances
Dimensionality increases three fold