What role does a capacitor play in a TENG power management circuit?

A capacitor in a TENG power management circuit serves primarily as an energy storage element and a voltage stabilizer. As an energy storage element, the capacitor accumulates and stores the electrical energy generated by the TENG. The TENG typically produces intermittent bursts of energy, and the capacitor acts as a buffer, smoothing out these fluctuations and providing a more stable and continuous power supply to the load. As a voltage stabilizer, the capacitor helps to reduce voltage ripple, which is the fluctuation in DC voltage caused by the incomplete suppression of the AC component after rectification. The capacitor charges when the voltage from the TENG is higher than its current voltage and discharges when the voltage from the TENG is lower, effectively smoothing the voltage output. The capacitance value determines the amount of energy that can be stored and the degree of voltage smoothing. A larger capacitance provides more energy storage and better voltage stabilization but may take longer to charge. For example, a capacitor can be used to store energy harvested from a TENG during short bursts of activity and then release it gradually to power a sensor or other low-power electronic device over a longer period.