PHOTOVOLTAIC INVERTER AND CORRESPONDING SWITCH FREQUENCY CONTROL METHOD

A photovoltaic inverter is provided, including an inverter circuit (10), a data sampling module (20), and a control module (30). The inverter circuit (10) includes a switch component (101) and an alternating current output terminal (104). The data sampling module (20) is configured to collect, from the alternating current output terminal (104), an instantaneous current value at each sampling point moment in target sampling duration and an instantaneous value of each-phase current at a target moment. The control module (30) is configured to: determine a valid current value of the target sampling duration based on the instantaneous current value at each sampling point moment, determine an upper switching frequency limit and a lower switching frequency limit of an N switching period based on the valid current value, determine a target instantaneous current value I based on the instantaneous value of each-phase current at the target moment, and determine a target switching frequency f of the N switching period based on the target instantaneous current value I, the upper switching frequency limit F, and the lower switching frequency limit F, to use f to control the switch component. In this way, conversion efficiency of the photovoltaic inverter can be improved on the premise of ensuring grid-connected stability.