MICRO INVERTER AND CURRENT MEASUREMENT METHOD

This application provides a microinverter and a current detection method. The microinverter includes: a primary-side circuit, configured to connect to a photovoltaic module, and convert a direct current output by the photovoltaic module into an alternating current; a transformer, where a primary-side winding of the transformer is coupled to the primary-side circuit, and the transformer is configured to boost or buck the alternating current obtained through conversion of the primary-side circuit; a secondary-side circuit, where a secondary-side winding of the transformer is coupled to the secondary-side circuit, and the secondary-side circuit is configured to convert an alternating current obtained through boosting and bucking into a power frequency alternating current, and is configured to output the power frequency alternating current to a power grid through an output port; and a current detection circuit, including a current transformer. The current transformer is located between the secondary-side winding of the transformer and the secondary-side circuit. The current detection circuit is configured to: collect a high-frequency alternating current of the secondary-side winding via the current transformer, and detect, based on the high-frequency alternating current, the alternating current output by the output port. A component in the alternating current detection circuit in this application has a small volume and low costs, and is suitable for use in the microinverter.