PROJECT TITLE :

Non-linear PWM Controlled Single-phase Boost Mode Grid-Connected Photovoltaic Inverter

ABSTRACT:

One-phase boost mode solar grid linked inverter with limited storage inductance current controlled by nonlinear pulse width modulation is proposed in this research For this type of inverter, extensive research is done on the circuit architecture and control method as well as steady-state principle characteristics and design criteria for key circuit parameters. In order to obtain high-quality grid-connected current, the inverter's regenerating energy duty ratio 1-D, which falls with the fall in grid-connected voltage, is real-time changed by sampling and feeding back the inverting bridge modulation current. Switching patterns, such as the "boost" and "freewheeling" patterns, can be used to adjust and balance the voltage step-up ratio of the energy storage inductance by connecting a bypass switch in parallel with it. Analysis and experimentation of the 1 kVA 110 VDC/220 V50 Hz solar grid-connected inverter prototype reveal its advantages, including a single-stage boost conversion, high efficiency and quality of grid-connected current waveform, low value of energy storage inductance, and simple control.