The increase in the PV installed capacity has also sparked a continuous evolution of the PV power conversion stage. Gradually, PV power converters have be come extremely efficient, compact, and reliable, allowing the maximum power to be obtained from the sun in domestic, commercial, and industrial applications. The PV converter industry has evolved rapidly from childhood to adult- hood in the last two decades and has become a distinct power converter category in its own right. One of the drivers behind this progress is that the PV converter market demanded very hard- to-meet specifications, including high efficiency (above 98%), long warranty periods (to get closer to PV module warranties of 25 years), high power quality, transformerless operation, leakage current minimization (imposes restrictions on the topology or modulation), and special control requirements such as the MPPT. Another driver behind this development is the fact that, for long time, the power converter represented a small fraction of the cost of the whole PV system due to high PV module prices, allowing PV inverter manufacturers room for developing higher performance and more sophisticated topologies. These topologies usually included more power electronics devices than the classic to pologies used in general applications, which have added control degrees of freedom that can be used to make the inverter operation more efficient, as will be addressed later in this article.