Definition of Power Diodes, Introduction to Waveforms of Dynamic Processes in Power Diodes 2

The dynamic process of a power diode involves its operating state in AC circuits, encompassing both the conducting and blocking phases. Throughout the AC cycle, the operating state of the power diode varies with voltage changes, generating specific waveforms.

Guidance process:diode

When the AC input voltage becomes positive, the diode begins to conduct. During this process, the diode voltage rises from zero to the threshold voltage (forward voltage), at which point the depletion layer disappears, allowing electrons to flow from the N-region to the P-region, causing a rapid increase in current. The rate of current rise depends on the forward resistance of the diode and the external circuit. In an ideal scenario, the current rise exhibits a right-angled hypotenuse shape, but in reality, due to capacitive and inductive effects, the rising edge will have a certain slope. diode

Conduction maintenance:

After the diode is fully conducting, the current waveform will follow the positive half-cycle of the AC voltage. Ideally, the current waveform is identical to the input voltage waveform. However, due to the forward voltage drop, the voltage waveform across the diode will actually be lower than the input voltage by a constant value.diode