Search results
Results From The WOW.Com Content Network
In these cases, the leakage inductance limits the current flow to the desired magnitude. Transformer leakage reactance has a large role in limiting circuit fault current within the maximum allowable value in the power system. [2] In addition, the leakage inductance of a HF-transformer can replace a series inductor in a resonant converter. [41]
A different form of short-circuit testing is done to assess the mechanical strength of the transformer windings, and their ability to withstand the high forces produced if an energized transformer experiences a short-circuit fault. Currents during such events can be several times the normal rated current.
To minimize distortion of the pulse shape, a pulse transformer needs to have low values of leakage inductance and distributed capacitance, and a high open-circuit inductance. In power-type pulse transformers, a low coupling capacitance (between the primary and secondary) is important to protect the circuitry on the primary side from high ...
The circle diagram can be drawn for alternators, synchronous motors, transformers, induction motors. The Heyland diagram is an approximate representation of a circle diagram applied to induction motors, which assumes that stator input voltage, rotor resistance and rotor reactance are constant and stator resistance and core loss are zero.
Usually applied for transients after a short circuit current. Three states are considered: [5] the steady-state is the normal operating condition with the armature magnetic flux going through the rotor; the sub-transient state (″) is the one the generator enters immediately after the fault (short circuit). In this state the armature flux is ...
Circuit diagram for open-circuit test. The open-circuit test, or no-load test, is one of the methods used in electrical engineering to determine the no-load impedance in the excitation branch of a transformer. The no load is represented by the open circuit, which is represented on the right side of the figure as the "hole" or incomplete part of ...
Thermal modelling – The useful life of a transformer is partially determined by the ability of the transformer to dissipate its internally generated heat to its surroundings. [3] The comparison of actual and predicted operating temperatures can provide a sensitive diagnosis of the transformer condition and might indicate abnormal operation.
Transformer with gap and leakage flux. Gyrator-capacitor model of a transformer with a gap and leakage flux. The gyrator-capacitor approach can accommodate leakage inductance and air gaps in the magnetic circuit. Gaps and leakage flux have a permeance which can be added to the equivalent circuit as capacitors.