Design of Control Strategy for Parallel Single-phase Full-bridge Inverters

• Main Authors: Yu-Ren Chen, 陳昱仁
• Other Authors: Jonq-Chin Hwang
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/4xdvtx

碩士 === 國立臺灣科技大學 === 電機工程系 === 107 === This thesis aims to design the control strategy for parallel single-phase inverters. The proposed system is composed of several independent inverters and human machine interface(HMI). The single-phase full-bridge inverters and voltage and current closed-loop control is used to stabilize output voltage and current. The graphical control software, LabVIEW, is adopted to implement the communication between modules and system monitoring. Once a module breaks down, the faulty module can be detected and cut off. The operating mode and power setting would be quickly redistributed to each module. Besides, to improve the total output capacity and power supply reliability, the controller area network(CAN) is adopted as the communication media between each inverter and HMI. The digital signal processor, TMS320F28069, is adopted as control kernel of single-phase inverter. Master-slave control is introduced to implement the parallel operation control. One of modules would be the master module under voltage closed-loop control, the others would be slave modules under current closed-loop control. In power distribution, the active current sharing mode is adopted to make output power of each module in average. The experimental results show when the three modules are operated at load of 1kW, the average output voltage RMS value and its total harmonic distortion(THD) is 111.10V and 2.50%, respectively. The corresponding current values are 3.15A and 4.74%. The system efficiency is 0.951. When a module breaks down, the other two inverters are operated at load of 1kW, the average output voltage RMS value and its THD is 110.66V and 2.39%, respectively. The corresponding current values are 4.52A and 2.90%. The system efficiency is 0.954. In post-fault control with uninterruptible system output, the operation mode transformation and the cut-off of faulty module are implemented under the load condition of up to 1 kW. The feasibility of the proposed system and control strategy is verified by simulation and experimental results.