A recording of the output of the emf induced for star and delta are re...
In a star connected transformer, closed path to generate 3rd harmonic is not there. So the emf shape will be peaky in nature.
View all questions of this test
A recording of the output of the emf induced for star and delta are re...
The shape of the induced electromotive force (emf) in a Y-connected 3-phase transformer is non-sinusoidal in nature due to the absence of the 3rd harmonic component of currents.
The Y-connected 3-phase transformer consists of three primary windings connected in a Y or star configuration and three secondary windings also connected in a Y configuration. When a balanced three-phase voltage is applied to the primary winding, a balanced three-phase current flows through the windings.
The balanced three-phase current consists of fundamental and harmonic components. The fundamental component has a frequency equal to the supply frequency, while the harmonic components have frequencies that are integer multiples of the fundamental frequency. The 3rd harmonic component has a frequency three times the fundamental frequency.
When the current flows through the windings, it produces a magnetic field that links the windings and induces an emf in the windings according to Faraday's law of electromagnetic induction. The induced emf in each winding depends on the rate of change of the magnetic flux linked with the winding.
In a Y-connected transformer, the 3rd harmonic component of the current is absent. This is because the Y-connected transformer does not provide a path for the flow of the 3rd harmonic component of the current. As a result, the rate of change of the magnetic flux linked with the windings does not have a 3rd harmonic component.
The absence of the 3rd harmonic component of the current leads to a non-sinusoidal shape of the induced emf. The emf waveform will have a distorted shape, deviating from the ideal sinusoidal waveform. It will contain higher-order harmonics and exhibit waveform distortion.
On the other hand, in a delta-connected transformer, the 3rd harmonic component of the current is present. This is because the delta connection provides a path for the flow of the 3rd harmonic component of the current. As a result, the rate of change of the magnetic flux linked with the windings includes a 3rd harmonic component.
In summary, the shape of the induced emf in a Y-connected 3-phase transformer is non-sinusoidal due to the absence of the 3rd harmonic component of the currents. This absence results in a distorted waveform with higher-order harmonics.
To make sure you are not studying endlessly, EduRev has designed Electrical Engineering (EE) study material, with Structured Courses, Videos, & Test Series. Plus get personalized analysis, doubt solving and improvement plans to achieve a great score in Electrical Engineering (EE).