Calculation of losses in rectifier diodes

The application process of rectifier diodes in circuits will generate losses. How can we reduce the losses of rectifier diodes during use? How should the loss of rectifier diodes be calculated?

Firstly, let's discuss the calculation and design of RC Sunbber for diodes. The essence of RC absorption is transfer loss. Since the voltage across the capacitor cannot suddenly change, it can suppress voltage spikes, while resistance is purely a damping oscillation function,

The industry has never recommended using testing methods, as the calculated results may differ from the actual ones.

The debugging method is as follows: first measure the oscillation waveform, read the oscillation frequency, then add C to halve the oscillation frequency, calculate the parasitic capacitance and inductance of the circuit, and finally determine the size of the series resistance based on the characteristic parameters of the oscillation circuit, or directly

Connect the resistance test until the oscillation has basically disappeared.

As for whether RC is purely a transfer efficiency, it has been experimentally proven that unreasonable RC parameters can reduce efficiency, while reasonable RC can actually improve efficiency. When RC is unreasonable, there is a high probability that there is a problem with the selection of C or R. C

The larger the R damping, the greater the loss, and when the R damping is insufficient, it can actually cause severe oscillations. But C is too small, and its ability to absorb spikes is not enough. So we can only adopt the method of measuring, calculating, and then debugging. It's a compromise choice.

A relatively common and simple design method is to test the oscillation frequency before adding absorption. If the frequency is f, then start to connect the capacitors, and the oscillation frequency of the capacitors will naturally decrease. So how many capacitors should be connected? After adding capacitor C, let it oscillate

The frequency has become half of its original value, which is 0.5f.

This way, another parameter that causes oscillation, inductance L, can be calculated based on the above parameters. Finally, take R=(L/C) as the root sign.

The loss of rectifier diodes during use is unavoidable, and professional use is necessary to improve the application efficiency of the circuit.