ZVS

ZVS, also known as Zero Voltage Switching, is a technique used in power electronics to improve the efficiency of switching power converters. The core principle of ZVS is to turn on power semiconductor devices, such as MOSFETs or IGBTs, only when their voltage across them is zero. This minimizes switching losses, which are a major source of inefficiency in traditional switching circuits.

In a ZVS circuit, an inductor is typically placed in series with the switching element. This inductor stores energy during the switching transition. When the switching device is turned off, the inductor releases its stored energy, causing the voltage across the switching device to momentarily dip to near zero before it starts to rise. If the switching device is turned on during this zero-voltage period, the power dissipated during the turn-on transition is significantly reduced. Similarly, Zero Current Switching (ZCS) can be employed for turn-off transitions, though ZVS is more commonly discussed due to the more significant impact of turn-on losses in many applications.

The benefits of ZVS include reduced heat generation, allowing for smaller and lighter power supplies, and the potential for higher switching frequencies. Higher frequencies enable the use of smaller passive components like inductors and capacitors, further contributing to miniaturization. However, implementing ZVS often requires additional components and careful circuit design to manage the resonant tank that facilitates the zero-voltage transitions. It is widely used in applications like switch-mode power supplies, power factor correction circuits, and induction heating.