Research On Control Strategy For Signal-Phase Photovoltaic Spwm Inverter Based On Repetitive Control

Development and utilization of new energy, such as solar energy, which are renewable and non-polluting is an effective sulotion for today’s energy crisis and environmental pollution. In recent years, solar power has become a focus of attention, as a device which changes forms of power resource, SPWM Inverter has also become a research hotspot. This paper focus on single-phase photovoltaic SPWM Inverter, analysises the topology and modulation detailly and have a depth study of repetitive control strategy for SPWM Inverter, the main work of this paper is as follows:1. After analysing the characteristics and working principle of the photovoltaic SPWM inverter, the topology this paper chooses is put out. Then, this paper elaborates the realization of SPWM modulation and SPWM wave production algorithms.2. The development of repetitive control theory is introduced, which focuses on the repetitive control in the inverter application. Then, this paper describes the various components of the repetitive controller and its general design procedure. A detailed analysis of the roles of every part of repetitive controller is made. Based on the model of inverter, this paper analyses the progress of designing repetitive controller for inverter in detail. Simulation results show repetitive control applied to SPWM inverter improves its control accuracy and voltage error is similar to the theoretical calculation error. In order to solve the shortcomings of poor dynamic performance, a strategy combining repetitive control and PI control is put out for inverter output voltage waveform control, simulation results show that the scheme improves the dynamic performance of the inverter.3. The general way to design repetitive controller is based on repeated adjustment for parameters of its each part, and, the repetitive controller includes a delay loop, leading to poor danimic performance. Taking this two shortcomings account, this paper puts out a method by which repetitive controller is achieved by solving a standard H∞problem, which reduces repeated process of adjusting the parameters and takes the system’s stability and tracking accuracy into account.Then this paper analysed each part of H∞repetitive controller and the design procedure of H∞repetitive controller in detail. In order to improve the overall performance of the inverter, H∞repetitive control based on inductor current state feedback is proposed, simulation results show that this strategy can be very good to overcome the transient voltage drop problem because of sudden load, even after joining the rectifier load inverter also can output sinusoidal voltage waveform of high quality.4. A experiment platform based on TMS320F2812is bulit. The design of hardware and software is described in detail.