Design of a Three Phase Multi-Level Inverter with Facts Capability for Distributed Energy

In this work, a wind energy inverter with flexible AC transmission system (FACTS) capability is presented. The proposed inverter is placed between the wind turbine and the grid, same as a regular inverter, and is able to regulate reactive power transferred to the grid. This inverter is equipped with distribution static synchronous compensators option in order to control the reactive power of the local feeder lines. Using the proposed inverter for small-to medium-size wind applications will eliminate the use of capacitor banks as well as FACTS devices to control the reactive power of the distribution lines. The goal of this work is to introduce new ways to increase the penetration of renewable energy systems into the distribution systems. This will encourage the utilities and customers to act not only as a consumer, but also as a supplier of energy. Moreover, designing such inverters with FACTS capabilities will significantly reduce the total cost of the renewable energy application. The inverter is designed in such a manner to meet all the requirements of a power system network such as compatibility with IEEE standards, total harmonic distortion (THD), efficiency, and total cost of the system. Here a three phase multi-level inverter is designed. The proposed control strategy regulates the reactive power using modulation index. PWM modulation technique is used. The function of the proposed inverter is to transfer active power to the grid as well as keeping the reactive power of the local power lines within the satisfactory limit regardless of the incoming active power from the wind turbine. The simulations have been done in MATLAB/Simulink.