Research On The Inverter Combined Single And Photovoltaic Grid-connected Mode

Photovoltaic grid-connected system and photovoltaic independent system are two main application field of photovoltaic technique, which is used in various situation. Therefore, the efficient integration of the two function will enlarge its range of application and decrease its cost. According to the characteristic of structure and control, grid-connected generation and independent power are integrated in one system successfully. The main study of this paper as follows:1: Achieved the function of independent invert, grid-connected invert, SPWM charging,what more, the different modes could be switched. 2: Chosen an appropriated control strategy for independent inverter such as outputvoltage. The influence and compensation of dead-time is analyzed. 3: Compared and analyzed the control of current in grid-connected inverter. An hybrid control with forward feed and feedback is adapted in this paper, and the results of stability and fast response are satisfied. 4: Achieved the true maxim power point trace of solar array by adapting an improvedMPPT control, which trace the load power instead of the power of solar array. 5: Active Frequency Drift to realize the anti-island function according to the reason ofisland effect.6: Designed the inverter with DSP(TMS320LF2407A) and its communication with W77E58.