Research on the control strategy of inverters in the micro-grid
- Xiangdong Sun
- Power and Energy Engineering Conference (APPEEC),
Despite all benefits of Micro-Grid, It creates many problems; one of the most common is their frequency instability. Because the Micro-Grid includes dynamic generations and loads then these units make real power imbalance. These components mainly include: wind turbines, Photovoltaic and dynamic loads. The rest of other components of Micro-grid are Gas Micro-Turbine (MT), Elecrtolyzer System (ES) and Fuel Cell (FC). Because, these units include MT, ES and Fc, are more controllable and observable, so they can help to increase the freedom degree of Micro-Grid' control. For achieving this aim, the state feedback method is used. Also for removing of disturbance due to mentioned dynamic units of micro-grid, more than state variables of Micro-Grid, it is necessary that the new state variable as name as integral of power deviation is added to system too. In other word, the applied approach for control Frequency improving is state feedback with integral control. By controlling all of controllable units (MT, FC, ES) and feeding back the integral of the tracking error, it can be guaranteed that at any moment, output (power deviation) converges to set point (zero). In this paper, integral state feedback gains is determined using PSO algorithm, and minimizing the maximum of eigenvalues is chose as objective function of optimization problem. The proposed control method is applied to damp the frequency fluctuations and enhance the power imbalance. In this paper, all of the simulation and analysis is done in isolated mode, and to show effectiveness of state feedback controller, the results of proposed controller is compared with results obtained from PI controller.