Maximum Power Point Tracking Of Photovoltaic System Based On Improved MPC Algorithm

Traditional fossil fuel is a kind of non-renewable energy.The burning of fossil fuels produces a lot of harmful gases that causes the environmental pollution.So,human being is faced with the problem of resource shortage and environmental pollution.As a kind of renewable clean energy,solar energy is widely used in the world.In order to improve the photoelectric conversion efficiency of solar energy and enable it to output high-quality electric energy more stably,efficiently and continuously,it is necessary to research on the maximum power point tracking technology in depth.The traditional method of MPPT can not fully achieve the tracking effect in the case of the dramatically changing environment,and there will be some errors,and the tracking speed and tracking accuracy can not meet the requirements at the same time.Based on this,the MPC algorithm in the artificial intelligence algorithm and the traditional method are combined to control the MPPT,so that the photovoltaic array can output as much power as possible,and also meets the requirements of tracking accuracy and tracking speed.Firstly,the mathematical model is derived according to the equivalent circuit of the photovoltaic cell.The simulation model is built in the Simulink simulation environment.The photovoltaic array is simulated at different temperatures and light intensities.Different traditional algorithms for MPPT control are compared and analyzed,and the perturbation observation method is selected as the basic algorithm and improved.Build PV system MPPT control circuit,including selection of DC/DC converter circuit,PWM control circuit,etc.The P&O method and the improved P&O method are added into the simulation circuit for simulation analysis,the result indicates that the improved perturbation observation method could effectively suppress voltage fluctuation and reduce power loss,but the tracking accuracy and tracking speed are not up to the requirements.Secondly,it introduces the model prediction algorithm in detail and this algorithm is derived,due to the large amount of calculation,there is a certain degree of redundancy.Therefore,the conditional trigger is set to be based on the conditional trigger,and the system reference threshold of the conditional trigger is adaptively optimized,the purpose is to improve computing speed,reduce the amount of calculation.The output voltage of the photovoltaic system is sampled and the predicted values of the two algorithms are compared.The result shows that the improved MPC algorithm requires less computation and can respond more quickly to the predicted value with larger error,and the predicted result is more accurate.Finally,the adaptive MPC algorithm is combined with the improved P&O method to control the MPPT circuit of the photovoltaic system.Simulation analysis is carried out in the Simulink simulation environment,and the output results are compared to verify the effectiveness and stability of the algorithm.Not only can the photovoltaic array work at the maximum power point to reduce voltage oscillation and reduce power loss,but also give consideration to tracking speed and tracking accuracy,so as to maximize the maximum power output of the photovoltaic array.