基于扰动观测器的广义风/光一体化控制策略研究

随着光伏、风电等分布式可再生能源高比例接入微电网,其发电出力不确定性给微电网的安全稳定运行带来显著的压力。提出了一种基于广义风/光同构模型的扰动观测器。首先通过建立风机接口整流器状态方程与光伏接口Boost电路状态方程的类比模型,提出了单输入单输出的风/光同构等效模型,使风机和光伏可以达到广义模型一致性。其次,针对光伏、风机等分布式能源出力不确定所造成的状态变量部分未知问题,通过引入连续时间模型的扰动观测器对等效的广义Boost模型进行控制,在光照或风速变化时,可以实现迅速跟随变化,同时随着时间的推移,扰动观测器可以实现无差调节,从而达到消除扰动而带来的部分状态未知的目的。更进一步,利用电压-电流双扰动观测器可以获得稳定的风/光混合系统的输出电压、电流及功率,并且输出量迅速达到给定值。最后通过仿真验证了所提出方法的有效性和可靠性。

Research on the Disturbance Observer Based Generalized Wind/Solar Intergration Control Strategy

With the high proportion of distributed renewable energy sources, such as photovoltaic and wind power, connected to the micro-grid, the uncertainty of its power generation output brings significant pressure to the safe and stable operation of the micro grid. Based on this, a disturbance observer based on generalized wind/solar isomorphic model is proposed. Firstly, by establishing the analogy model between the state equation of the interface rectifier and the state equation of the photovoltaic interface Boost circuit, the equivalent model of the isomorphic photovoltaic/wind turbine with single input and single output is proposed, so that the wind turbine and photovoltaic can achieve the consistency of the generalized model. Secondly, in order to solve the problem of partially unknown state variables caused by the output uncertainties of distributed energy such as photovoltaic and wind turbines, a continuous-time disturbance observer is introduced to control the equivalent generalized Boost model. When the illumination or wind speed changes, the disturbance observer can quickly follow the change. At the same time, with the passage of time, the disturbance observer can achieve no-difference adjustment, so as to control the equivalent generalized Boost model. The purpose of eliminating the partial state unknown caused by disturbance is achieved. Furthermore, the output voltage, current and power of a stable wind/photovoltaic hybrid system can be obtained by using a voltage-current double disturbance observer, and the output can quickly reach the given value. Finally, the effectiveness and reliability of the proposed method are verified by simulation.