How the transformer noise is caused
Specifically, the transformer noise is a total of three sound sources, one is the core, the other is winding, and the third is the cooler, that is, no-load, load and cooling system caused by noise. The cause of the noise of the core is caused by the effect of the alternating magnetic field of the core silicon steel sheet, the small change is the magnetostrictive, the magnetostriction makes the core vibrate periodically with the excitation frequency variation, the core magnetostrictive deformation and the winding, the fuel tank and the magnetic shielding inner electromagnetic force. The reason for the vibration of the winding is that the electromagnetic force is produced in the current winding and the leakage magnetic field can make the structure vibrate.
The reason of electromagnetic noise is that the magnetic field induces the noise of the core laminations along the longitudinal vibration, and the amplitude of the vibration is related to the magnetic flux density and the magnetic properties of the core material in the core laminations, but it has little relation with the load current. The electromagnetic force (and amplitude of the vibration) is proportional to the square of the current, and the transmitting sound power is proportional to the square of the amplitude of the vibration.
What is the difference between transformer triangulation and Y
The common transformer windings have two kinds of connections, that is, triangular wiring and star-shaped wiring; In the transformer's join Group D is the triangular wiring, Y is the star-shaped belt neutral line wiring, y means the star shape, n means the neutral line; indicates that the line voltage of the Transformer two times is UAB hysteresis UAB330 degree (or 30 degrees ahead).
The method of the transformer's joining group is: The uppercase letter indicates the wiring mode of one side (or the original edge), and the lowercase letter indicates the wiring mode of two times side (or side). Y (or Y) for star wiring, D (or D) for triangular wiring. The digital clock notation is used to denote the phase relationship of the secondary line voltage, and the first side voltage phase is used as the minute hand, which is fixed at the 12 point of the clock, and the linear voltage phase at the two sides is used as the hour.