Z-source inverter based control of wind power

Impedance (Z)-source inverter can provide stable output by smooth controlling of shoot-through duty cycle of any of the traditional PWM bridge inverters. In this paper a control system for impedance-source inverter is designed suitable for wind power conversion system. The main challenge in wind power system to maintain a constant voltage at the output with unpredictable variation in wind speed, is suitably taken care in steady state through buck-boost-capability of z-source inverter (ZSI). The shoot through state of ZSI is able to control and boost the output voltage when the wind generator voltage is not more enough to directly generate the desired output. Again, the non-shoot through state can control and buck the output voltage when the wind generator voltage is more than desired. So, the z-source PWM inverter replacing the conventional PWM inverter provides the unique output voltage regulation feature by making an appropriate choice of buck-boost factor. The closed loop controller carefully monitors the wind generator voltage and controls the shoot-through and non-shoot through duty cycles automatically. The whole system is simulated under arbitrary input variation condition and results are presented. A comparison between the traditional and z-source inverter based system is also presented, which clearly indicates the benefits of the proposed system.