抄録
This paper presents a three-phase PWM current source inverter-induction motor drive system with photovoltaic generation. The system is interacted to single-phase utility using PWM converter, and the photovoltaic arrays are connected to the dc link of the system by employing a step-down chopper. The chopper is operated on PWM switching, and contributes to maintain the maximum power of the arrays and to smooth the dc link current in the small dc reactor. The PWM converter can flow the power in bidirection between the system and the utility with a sinusoidal current in the ac side.
In this paper, the system configuration and the control methods are shown. First of all, the PWM strategy of the chopper, which depends on the converter PWM operation, is explained in detail and the switching patterns are given. Next, the experimental and the theoretical results at the steady state operations are given, and it is shown that the use of the PWM chopper is effective for the improvement of the ac waveforms. Finally, the waveforms at the transient operation are given in the variable speed drive of the motor and the change of the sunlight quantity for the arrays. The results prove that the proposed system has good performances for the utilization of the photovoltaic power.
