Why Apparent Power Exceeds Real Power in Diode Rectifier Circuits

In diode rectifier circuits, the current flows in pulses because the diodes only allow current to flow in one direction. The voltage waveform is also not a perfect sinusoidal waveform. This means the RMS voltage and current are not in phase with each other, leading to a power factor less than 1.

The product of the RMS voltage and current (apparent power) represents the total power consumed by the circuit. However, since the power factor is less than 1, the actual power delivered by the circuit (real power) is lower than the apparent power. Real power is the power actually used by the load and is calculated by multiplying the RMS voltage, RMS current, and the power factor.

Diode rectifier circuits typically have a low power factor due to the non-sinusoidal waveforms and the phase difference between the voltage and current. Consequently, the apparent power is higher than the real power.