What happens to the ripple voltage when the capacitance of the filter capacitor is increased?

When the capacitance of the filter capacitor is increased in a power supply circuit, the ripple voltage decreases. This occurs because a larger capacitance provides a greater charge storage capacity.

In a rectifier circuit, the filter capacitor smooths out the fluctuations in the output voltage produced by the rectification process. When the load draws current, the stored energy in the capacitor helps maintain a more stable output voltage. Therefore, with a larger capacitor, it can discharge more slowly over time during the intervals when the input voltage is momentarily low. This results in a smaller voltage change (or ripple) between the peaks and valleys of the output waveform.

In contrast, a smaller capacitance would lead to greater fluctuations in voltage, as the capacitor would deplete its charge more rapidly, causing the ripple voltage to be higher. Hence, increasing the capacitance effectively reduces the ripple voltage in the circuit.