| 摘要 |
The present invention relates to a high-efficiency grid-connected inverter circuit, provided with a half-bridge inverter or a three-level inverter and two DC/DC converters having no LC output filters, or provided with a single-phase inverter and a single DC/DC converter having no LC output filter. When the absolute value of grid voltage is less than the input voltage, the inverter performs SPWM modulation and the DC/DC converter is idle; when the grid voltage absolute value is greater than the input voltage, a DC/DC converter performs SPWM modulation, and the corresponding electronic switch in the inverter remains in a conductive state, thus transmitting energy directly to the electrical grid. It can thus be seen that the circuit at any time actually only performs single-level SPWM conversion, thus greatly reducing switching loss throughout the entire circuit and improving the conversion efficiency of the grid-connected inverter. |
