Cascaded H-bridge multilevel inverters can not only implement the distributed maximum power point tracking (MPPT) with high photovoltaic utilization, but also decrease the switching losses, improve the inverter efficiency and output waveform quality, which is popular in the field of large-scale photovoltaic (PV) grid-connected system research and engineering applications. Firstly, cascade multilevel photovoltaic grid inverter control strategies are reviewed in recent years. Secondly, the power balance control strategies of the converter are divided into three categories according to the different modular modulation methods, and their control principles and characteristics are analyzed in detail. Then the power imbalance constraints of various control strategies are derived. Lastly, methods of improving the topology and control strategies of cascaded H-bridge multilevel inverters are presented.