The Research Of Sine-Wave Inverter Power Supplies

With the rapid development of power electronic AC power supplies are widely used in a lot of fields. The requirement output waveform of AC power supplies is rising. The output quality of AC power supplies mainly includes three aspects. One is the accuracy of stable output waveform; the second is the good transient response; the third is the good load compatibility. So research on AC power supplies which are not only simple, but also have better transient and stable performance is always the last aim in the tectonics field of AC power supplies. In order to get high quality and high reliability power supplies, this paper presents the study of Multiple-loop feedback control scheme, output phase control, the analog and digital control system of AC power supplies.This thesis research the principle of AC power supply-control, then builds the system dynamic model of AC power supplies. The AC power supply -performance of adopting a variety of single loop control methods are researched contrastively .At last Multiple-loop feedback control scheme suitable for high-performance AC power supplies has been adopted for this paper. Because the output voltage-phase lag the standard sine-phase, this thesis firstly makes use of the voltage instantaneous loop to control the output lagging-phase, this scheme is valid, but output-phase has steady-state error. Aim at this, this thesis presents a novel phase control scheme, which makes output voltage without steady-state error,this scheme introduces the phase forward net to control output lagging-phase at the basis of the voltage instantaneous loop . The validity of this scheme has been verified by the result of simulator and experiment. The main circuit parameters have been researched in this paper, which includes inverter circuit , absorb circuit, drive circuit, transformer and filter .The reason of transformer bias magnetization are analyzed, At last measures of valid restrained bias magnetization are given. Thanks to Multiple-loop feedback control scheme, The system has excellent voltage regulation performance, fast dynamic response> good disturbance rejection and high nonlinear load compatibility. At last, 2KVA - experimental prototypes of AC power supplies of multiple-loop analog and digital control system have been made. Fast dynamic response and load compatibility have been verified by the experiment of step change in the load and under rated full-wave diode bridge rectifier load.