This invention provides a solar photovoltaic system, comprising: a plurality of photovoltaic assemblies, for harvesting solar energy to generate DC currents; a plurality of micro-optimizers having input terminals coupled to the photovoltaic assemblies and having output terminals connected in series with each other, for optimizing output currents and/or output voltages of the photovoltaic assemblies, to generate maximum power; a manager configured to communicate with the plurality of micro-optimizers, for managing operating states of the micro-optimizers; and an inverter coupled to one or more strings of the micro-optimizers, for converting the optimized DC currents into AC currents and outputting the AC currents to a power grid. This invention further provides a method for energy harvest optimization and a method for fault detection of a solar photovoltaic system.