Based On The Three-phase Dsp28335 Photovoltaic Inverter Is Developed

In recent years, photovoltaic inverter as a photovoltaic system energy conversion device, which determines the stability of the system and the conversion efficiency, is an important part of research and development.This article designs a lOkVA three-phase PV inverter which based on32of the DSP28335. It has used two high-frequency inverter technology. With DC-DC converter to boost the voltage, three full-bridge inverter circuit complete the function of the inverter.The inverter was researched from the following aspects in this article:1. The development of grid-connected PV research background and significance of domestic and international photovoltaic inverter’s status are well summed up.2. The basic principle of Boost chopper circuit, and the topology of three full-bridge inverter circuit which will be chosen was described in detail. And the fulfillment of PID algorithm is discussed in details, three-phase full-bridge inverter closed-loop control strategy and its implementations are analyzed in this article.3. The main components in the system were given the selection and detailed calculations, including the selection of IGBT, IPM, the boost inductor, the filter inductor. Modular design of the three-phase PV inverter hardware circuit, including the designs for power circuit, acquisition and processing circuit, driving circuit,master control circuit and so on. In the power circuit, IGBT was used as the Boost circuit power module and IPM was used as a three-phase full-bridge inverter circuit. TI’s DSP28335was taken as the core chip in master control circuit.4. Software programming. The software is divided into four subprograms including main program, signal acquisition and processing subprogram, voltage and current control program, algorithm control subprogram. With Boost DC/DC converter using voltage closed-loop to step-up the voltage, three full-bridge inverter circuit to analysis SPWM program, and then the process of designing the program was concluded.PV inverter uses software to control input and output overload, short circuit protection and over-voltage and under voltage protection.5. Production of prototype and experimental study. In this paper, each circuit module was debugged respectively. After successful commissioning of the entire circuit was consolidated and developed a lOkVA three-phase PV inverter power prototype, the experimental waveforms were given. The test results verify the reliability and practicality of the design of the inverter.6. The whole process of a photovoltaic grid-connected inverter is explored and researched; the usage of Phase-locked is depicted.