The hysteresis curve of the saturable inductor was created by using a nonlinear inductor and a nonlinear resistor in parallel as a substitute for saturable inductors. Once the circuit was built in matlab, simulations were run to. A threephase transformer is energized on a 500 kv network. The result of the circuit using the modelled inductor is found to be close to the result using the ideal inductor. Consider an inductor of 2 henries designed to operate at a nominal voltage, vnom 120 v rms, and a nominal frequency, fnom 60 hz. One phase of a threephase transformer is connected on a 500 kv, 5000 mva network. H curve tool psim provides a convenient way to define the parameters of a saturable core element. Sensors and actuators a 123124 2005 430437 application of. The current is defined to flow from the positive terminal to the negative terminal of the inductance. Matlab i about the tutorial matlab is a programming language developed by mathworks.
The transformer is rated 500 kv230 kv, 450 mva 150 mva per phase. This tutorial gives you aggressively a gentle introduction of matlab programming language. The power system is simulated by an equivalent circuit consisting of an inductive source. In the following sections, a simple saturable inductance and a nonlinear resistance serve as examples. Specify the units used to enter the parameters of the multiwinding transformer block. This example shows the transformer saturation phenomenon.
By connecting the air gap element in series with the core, we have the model for the inductor. Measured data provided was used in matlab to construct the curves for the nonlinear inductors and nonlinear resistors. From zero to 120 v rms the inductor has a constant inductance, l 2 h. The per unit conversion is based on the transformer rated power pn in va, nominal frequency fn in hz, and. The transformer rated 450 mva, 500 kv230 kv60 kv consists of three windings connected in yydelta. The simulated bh curve from the saturable core model creating the inductor model. It started out as a matrix programming language where linear algebra programming was simple. The six signals obtained at the output of the multimeter are the three currents in the circuit breaker and the three fluxes inside the core of the saturable transformer. A modified version of this example exists on your system. It can be run both under interactive sessions and as a batch job. Ripkac a power electronics research centre, department of electronic engineering, national university of ireland, galway, ireland b department of radiology, brigham and womens hospital, harvard medical school, boston, ma, usa.
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