Study On The Digital Control System Of Inverter For On-line UPS

With the fast development of information technology, more and more digital control systems are implemented in CVCF-PWM inverter system. Among all kinds of UPS, the performance of the on-line UPS is the best. It can provide the steady and pure sine wave power with little distortion. This article chiefly analysis the control system of inverters applied in on-line UPS, included the hardware and software design. The follows are concluded in this thesis.This thesis introduce the retrospection and the classification of the UPS, the characteristics of modern invert technology applied in UPS control technology are also summarized.The operation principium of the 3-phase VSI is especially analyzed. Based upon these conclusions, a compound control arithmetic which is formed by the repetitive control and the proportional control for inverter system is put forward.Based on the theory analysis, the hardware implementation block diagram of the inverter system is proposed. The corresponded hardware implementation, included the power system design and the control system design used TMS320LF2407A , are particularly analyzed.After the hardware implementation discussed above, the software design of the inverter system is described. The sequence, the interruption and data procession flowcharts are analyzed and their block diagrams are illuminated in details.At the end of the thesis, the experiment results of the prototype are provided. These results show that the proposed control scheme is valid and can meet the demand of UPS.