Two-stage photovoltaic grid-connected control device based on pole assignment and repetitive control combination

The utility model provides a two-stage photovoltaic grid-connected control device based on pole assignment and repetitive control combination. The device can invert direct current output by a photovoltaic cell into alternating current, and transmit the alternating current into the power grid to ensure less content of harmonic wave, high power supply quality and high system utilization efficiency, and the system stability can be improved to a certain extent, thereby improving the performance of the whole photovoltaic system. The two-stage photovoltaic grid-connected device has the advantages:(1) digital control is adopted, the interference resistance is strong, and the system can obtain excellent accuracy and stability; (2) the system has clear division, and the control effect is remarkable: a forward Boost converter realizes maximum power tracking, and a backward converter completes direct current side voltage stability and grid-connected inversion; and the system is reliable, and the robustness is good; and (3) the control algorithm is advanced: the dead-time effect of the converter and harmonic wave caused by nonpolar load can be overcome by using the repetitive control technology; and accurate control is realized by applying the pole assignment based on state feedback.