新能源电网中微电源并网控制策略研究

Control strategies for grid-connected microsource in new energy power systems

为了保证分布式发电安全并网运行,提高微电网的稳定性能,研究了微电源逆变器接口的鲁棒控制问题。该研究基于三相并网逆变器系统,建立了三阶数学模型。考虑到系统的动态模型参数的不确定性,基于Lyapunov鲁棒稳定方法设计鲁棒控制器,并将该鲁棒稳定性问题转换为线性矩阵不等式问题,给出保证系统稳定的充分条件。采用线性矩阵不等式的凸优化技术,可求得最小鲁棒性能指标和鲁棒控制器的参数。仿真结果证明了该控制方案的有效性。

For the purpose of enhancing stabilization performance of three-phase grid-connected inverter, the robust stability control of micro-source inverter interface is studied. Firstly, based on the three-phase grid-connected inverter system, the three-order mathematical model is established. Then, taking into account uncertain parameters in the system dynamic model, a robust controller is designed based on Lyapunov robust stabilization method. Some sufficient conditions for the system stability are presented in terms of linear matrix inequalities （LMI） only dependent on the robust performance index. By using the convex optimization technique of LMI in MATLAB toolbox, the minimum robust performance index and the parameters of the robust controller can be obtained efficiently. The effectiveness of the proposed control scheme is demonstrated through simulation examples.