The Research Of Grid-connected Three-phase PV Inverter System Based On DSP

Nowadays energy crisis and ecological protection make green energy to become a hottopic. Solar energy as the green energy, to be the focus of attention. Photovoltaic powergeneration technology is a great way of solar energy utilization.In photovoltaic powergeneration systems, energy conversion efficiency and stability of the system operation is thekey point of research.In this paper,two levels of non-isolated photovoltaic grid inverter system as the researchobject. First of all,by comparing with the traditional maximum power point tracking (MPPT)algorithm,in view of the existing problems,adopting simple method to control the outputvoltage can be used to the maximum power tracking.Secondly, this article carries on the comparison to inverter modulation technology, theprinciple of SPWM is straightforward, but due to the switching frequency increases the higherswitching loss, so the SVPWM modulation method is adopted to inverter modulation,not onlymake the output current harmonic content less,but also improve the utilization rate of dcvoltage, reduce the loss. For system control mode in this paper, based on the grid voltageoriented vector control technology, fast and efficient to control the system, improve thesystem stability and anti-interference ability. According to the design scheme of the controlsystem, using DSP as main control chip, designed based on TMS320F2812grid invertercontrol system hardware circuit and software. Hardware circuit including DC/DC circuit,inverter circuit, driving circuit, sampling circuit, etc. Combined with the correspondingsoftware control to realize the whole system is running..Finally, the system has carried on the simulation and experiment. The SVPWMalgorithm is designed in MATLAB/Simulink and the simulation model of three-phase gridinverter system. To verify this algorithm, the structures of TMS320F2812DSP as main controlchip of the two levels of photovoltaic grid inverter experimental platform for actualdebugging.The key to solve the SVPWM modulation of three-phase inverter and voltageoriented vector control to improve the conversion efficiency and system stability.