The Study On Digital Control Technique Of Inverter Based On DSP

With the development of modern technology, inverters are widely used. Meanwhile, various industries have set higher requirements on the performance of inverters. Good output waveforms of inverters have not only the good steady-state performance, but also the fast dynamic response. It is very difficult for single control strategy to satisfy the two requirements at the same time. Thus, hybrid control strategy is a developing direction because the strategy can take good advantage of every part while avoiding its default.This paper discusses the advantages and disadvantages of the prevalent digital control strategies, analyses the control principle of the deadbeat control and repetitive control in detail, and presents some improved measures about the control algorithm. Deadbeat control has a good dynamic response, but its steady-state performance is not satisfying especially when connected with nonlinear load; Contrarily, repetitive control has a good steady-state performance, but its dynamic response is poor because it includes a part of the cycle delay and the outputs of control orders have a reference cycle delay. In this paper, the main circuit of inverter is a single-phase full-bridge topology. Then establishes the continuous state-space model and discrete state-space model, analyses the open-loop output characteristics, introduces the design methods of parameters about the improved deadbeat controller and the repetitive controller.A hybrid contol strategy based on the improved deadbeat control and repetitive control is proposed. Establishes the simulation model of control system using MATLAB software, and the simulation results show that the hybrid control strategy can make the inverter get a good steady-state and dynamic performance. Finally, the paper introduces the hardware and software of the control system of inverter based on the DSP TMS320F2812.