Photovoltaic inverters can convert the variable DC voltage generated by photovoltaic solar panels into mains frequency alternating current (AC), which can be fed back to commercial power transmission systems or used by off-grid power grids. The photovoltaic inverter is one of the important system balance (BOS) in the photovoltaic array system, and it can be used with general AC power supply equipment. The solar water pump inverter has special functions that cooperate with the photovoltaic array, such as maximum power point tracking and islanding effect protection.
Solar water pump inverters can be divided into the following three categories:
Stand-alone inverters: Used in stand-alone systems, the photovoltaic array charges the battery, and the inverter uses the DC voltage of the battery as its energy source. Many stand-alone inverters also integrate a battery charger, which can charge the battery with AC power. Generally, this kind of inverter will not touch the grid, so it does not need islanding effect protection function.
Grid-tie inverters: The output voltage of the inverter can be fed back to the commercial AC power source, so the output sine wave needs to be the same phase, frequency and voltage as the power source. The grid-connected inverter will have a safety design. If it is not connected to a power source, it will automatically turn off the output. If the grid power supply trips, the grid-connected inverter does not have the power supply function.
Battery backup inverters are a special kind of inverter. The battery is used as its power source, and the battery charger is used to charge the battery. If there is too much power, it will be fed back to the AC power source. This kind of inverter can provide AC power to the specified load when the grid power is tripped, so it needs islanding effect protection function.