The ac-module configuration uses a dedicated grid-tied inverter for each PV module of the system [15]. Therefore, this configuration is also known as a module-integrated inverter and microinverter because of the small size and low power rating of the converter. The LV rating of PV modules (generally around 30 V) requires voltage elevation for grid connection. This is why ac-module inverters are only found with an additional dc–dc stage, usually with an HF transformer to provide galvanic isolation and elevate voltage. Because of the additional dc–dc stage and HF isolation, this is the configuration with the lowest power converter efficiency, which is compensated somehow by the highest MPPT accuracy due to the dedicated converter. This configuration is useful for places with lots of partial shading, complex roof structures, small systems, or combinations of different roof orientations. The small size of the converter allows a very compact enclosure design that can be attached to the back of each PV module, hence the name module integrated inverter. Because of their LV operation, metal– oxide–semiconductor field effect transistor (MOSFET) devices are most commonly found in these topologies. Nevertheless, this concept might benefit from new, faster, and more efficient semiconductor devices (SiC and GaN) and therefore gain more importance in the future.