Main features of rectifier transformers

The primary side of the rectifier transformer is connected to the communication power system, which is called the grid side; the secondary side is connected to the rectifier, which is called the valve side. The structure principle of the rectifier transformer is the same as that of the general transformer, but because the load rectifier is different from the general load, it has the following characteristics:

1. Each arm of the rectifier is turned on in turn in one cycle, and the conduction time only occupies a part of one cycle. Therefore, the current waveform flowing through the rectifier arm is not a sine wave, but a rectangular wave close to discontinuity; in the original and secondary windings The current waveforms are also non-sinusoidal.

When the thyristor is used for rectification, the larger the lag angle, the steeper the current fluctuation, and the more harmonic components in the current, which will increase the eddy current loss.

Because the conduction time of the secondary winding only accounts for a part of a cycle, the utilization rate of the rectifier transformer is reduced. Compared with the general transformer, under the same conditions, the volume and weight of the rectifier transformer are larger.

2. Generally, the primary and secondary power of the transformer are the same (negligence of loss), and the capacity of the transformer is the capacity of the primary winding (or secondary winding).

But for the rectifier transformer, the power of the primary and secondary windings may be the same or not equal (when the primary and secondary current waveforms are different, such as half-wave rectification), so the capacity of the rectifier transformer is the primary and secondary apparent power. The average value is called the equivalent capacity, that is, S1 is the apparent power of the primary side, and S2 is the apparent power of the secondary side.

3. Compared with ordinary transformers, the ability of rectifier transformers to withstand short-circuit electric power must strictly meet the requirements. Therefore, how to make products have short-circuit dynamic stability is an important issue in design and manufacturing.

The rectifier transformer is a transformer that provides a rectifier system. Its principle is the same as that of a general transformer. It is a device that converts AC voltage based on the principle of electromagnetic induction.