Grid Connected WECS with Multi-Level NPC Shunt Active Power Filter

This paper presents the efficient operation of three-level Neutral Point Clamped (NPC) Shunt Active Power Filter (SAPF) for interconnecting the WECS (Wind Energy Conversion System) to the utility grid using an extended reference signal generation scheme. The proposed topology provides wind power generation in addition to the current compensation function. The SAPF wants a supply of energy for compensate the current based disturbances in the load current, which utilizes the WECS with DC-DC converter like a DC power source. The shunt connected inverter controls the DC-link voltage along with the active and reactive power transferred from the renewable energy sources to grid with improved power quality. The modified p-q theory is used for reference current generations. To maintain the DC link voltage as constant and compensate the power losses of the Voltage Source Inverter (VSI) a PI controller is used in the outer control loop. The gating signals for the switches are generated from the carrier based Sinusoidal PWM (SPWM) technique. The main features of the proposed system are that it will provide the continuous current based compensation for throughout the day and recompense the voltage interruption. These systems make use of the wind energy and accordingly save the electrical energy and offer uninterruptable power supply to important/sensitive load. The simulation results are presented to verify the effectiveness of the proposed configuration.