The stable performance of the output voltage represents the stable voltage capacity of the output voltage of the inverter. General photovoltaic inverter products are given when the DC input voltage changes in the allowed fluctuation range, the percentage of the output voltage fluctuation deviation of the inverter is usually called the voltage adjustment rate. The high performance inverter should also give the percentage of deviation of the output voltage of the photovoltaic inverter when the load changes from zero to 100%, which is usually called the load adjustment rate. The voltage adjustment rate of photovoltaic inverter with good performance should be less than or equal to ±3%, and the load adjustment rate should be less than or equal to ±6%.