采用了一种基于重复原理的无差拍控制单相逆变器的控制方案,即根据无差拍控制中的周期预测与重复控制的相似性,利用谐波信号的周期性进行预测与控制。通过重复控制器来修正无差拍控制中由于各种原因而造成的周期性的控制偏差,对重复控制器各环节进行合理的设计以改善系统的动态性能和稳态性能。该控制方案既保留了无差拍环节动态响应快的特点,又吸纳了重复控制无稳态误差的优点。系统处于稳定运行状态时,重复控制可增强系统抗周期性干扰能力,改善系统稳态特性;负载出现大的扰动时,无差拍环节可感受到输入误差的突变并立即产生调节作用,保证系统有较快的响应速度。对该控制策略进行了全面的理论分析,基于理论分析,在Matlab中对该系统进行了仿真设计,同时搭建了一个单相SPWM逆变器的硬件平台,在该硬件平台上采用数字控制算法实现了该控制方案。仿真与实验结果均表明,与传统的无差拍控制相比该控制方案能获得更好的动、稳态性能。
An deadbeat control strategy scheme based on repetitive principle in single- phase inverter was adopted, namely utilizing the periodicity of harmonic signal to predict and control on the basis of the similarity of periodical prediction and the repetitive control. The repetitive controller was used to amend periodic control deviation resulting from different kinds of factors in deadbeat control, thus to design each link of repetitive controller reasonably to improve the dynamic performance and steady-state performance of the system. This control scheme not only retains the characteristics of fast dynamic response from deadbeat control, but also absorbs the advantages of no steady-state error in repetitive control. When the system Was in stable operation condition, repetitive controller was used to resist periodic disturbance and thus improvd the steady-state performance. Contrarily, the deadbeat control component can feel mutation of input error and produce accommodation immediately to ensure the system' s fast speed of response. The comprehensive theoretical analysis of this control strategy was given, and the system was designed in Matlab based on this theory, simultaneously the hardware platform of single SPWM inverter was setted up, and the control scheme was achieved in the hardware platform by using digital control algorithm. Simulation, and experimental results prove that the proposed scheme can achieve better dynamic and steady-state performance compared with the traditional deadbeat control.