Research On The Control System Of A Special Three-phase Inverter Power Supply

As an important part of AC power supply, three phase inverter is widely used in the fields like industry, energy, transportation and so on. The three-phase inverter studied by this paper is mainly used for ship. It is a Special Power Supply for turbo generator accessories oil pumps and diesel generator pumps. The inverter power source should have good Loading Capacity and dynamic performance to adapt to the operations with load. The inverter is powered by the rectified power of the boat when the master power is normal. However, if power of the boat is failed, the inverter will be powered by the battery. In order to make sure turbo generator accessories oil pumps and diesel generator pumps work well, it needs to ensure the stability of the DC bus voltage of the inverter even when input voltage and load are different. So it is very important to research the special three-phase inverterFirst, this paper establishes the mathematical models of single and dual loop controllers for the boost converter. The dual loop includes outer output voltage loop and inner average inductance current loop. In addition, in order to improve the dynamic performance of the system, an improved single closed-loop controllers with input voltage feed-forward is presented.Secondly, this paper also deduces the mathematical model of the three-phase inverter in abc coordinate system、αβ coordinate system and dq coordinate system. Then, it makes the analysis of the dynamic performance of the system as well as steady-state performance under dual-loop control. Finally, the results were verified by experiments.Again, the article describes two ways of the software phase-locked loop by DSP. Then it respectively introduces the working principle of software phase locked-loop based on single-dq synchronous transform and dual-dq synchronous transform. And we also makes comparative analysis of their performance by simulation under power system fault conditions. In addition, experiments prove that the performance of software phase-locked loop based on single-dq synchronous transform is good.Finally, this paper gives a brief description of the entire experimental platform. And then we make the experiments with the whole system. It proves that the overall design is feasible and the control parameter is reasonable.