Design and analysis of a hybrid renewable energy plant with solar and wind power

•A distributed generation system is developed with separate solar plant and wind turbine.•The solar plant is controlled with MPPT infrastructure of Perturb&Observe algorithm.•Power generation of source sites are converted to DC with PI controlled buck converters and collected on a DC busbar.•Harvested DC power is converted to AC with a full bridge inverter and SPWM control is performed in inverter.•The total harmonic distortion (THD) ratio of the generated 3-phase line is obtained in the limit of standards. A hybrid renewable energy plant that is based on solar and wind energy conversion systems is designed and analysed in this paper. Each separate energy conversion system is controlled either using regular PI controller or extended PI controller with an auxiliary controller containing Perturb and Observe algorithm. The solar plant model is constituted by connecting 170W photovoltaic (PV) panels serially and energy conversion is performed with maximum power point tracking (MPPT) algorithm that controls the modulator of buck converter. The MPPT algorithm utilized in the control step of converter is developed using Perturb and Observe (P&O) that is extended with PI controller. The wind energy plant is designed with a permanent magnet synchronous generator (PMSG), and the AC–DC conversion stage is constituted with an uncontrolled full-bridge rectifier. All the converter outputs are connected to a busbar over interphase transformers (IPTs). The DC bus-bar voltage is supplied to a full bridge inverter to generate three-phase AC voltages at the output of inverter. The three-phase inverter is controlled with sinusoidal pulse width modulation (SPWM) scheme, which is developed with phase shifted carrier signals. The total harmonic distortion (THD) ratios are obtained at proper values according to international standards such as IEC61000 and IEEE 519-1992. Measurement results and obtained three phase voltage are analysed in detail.