Research On The Impact Of Electric Vehicle Access On The Micro-grid Power Quality And Harmonic Suppression Strategy

With the continuous development of renewable energy microgrid system such as wind energy and solar energy,electric vehicle charging system will become one of the important loads in the development of microgrid in the future development.The access of electric vehicle charging device is unavoidable Micro-network introduction of harmonics,affecting the micro-network and power grid power quality.Micro-network is weak inertial system,anti-interference ability is relatively weak power grid is weak,so how to ensure that micro-network to meet customer service requirements efficient and reliable operation,is the micro-grid power quality control one of the direction of development.In this thesis,the energy storage system of microgrid is taken as the research object,and the active control strategy of realizing the power quality of microgrid by using the converter of the energy storage system is put forward.The energy storage system includes the micro-net energy storage device and the electric vehicle in the electric car charging station of the energy storage device can simultaneously control the micro-network harmonic pollution,but also in the micro-network power fluctuations and emergency situations for the micro-network to provide the necessary power support to improve the quality of micro-grid power.Firstly,this thesis introduces the development of microgrid and the status quo of research at home and abroad,the power quality problems brought by electric vehicles after access to microgrid and the power quality problems such as harmonic pollution caused by microgrid itself,focusing on the access to electric vehicles The main causes of the power quality problem caused by the micro-network or the grid are analyzed,and the main measures to suppress the harmonic pollution of the micro-network or the power grid are analyzed and summarized.At the same time,the electric car charging station and the microActive power filter(APF)function of the active harmonic suppression structure of the energy storage device how to achieve APF function analysis,and describes its working principle,based on the instantaneous reactive power theory id-iq method to detect harmonics And the grid control of the energy storage device,a unified control strategy of energy storage converter is proposed,and the strategy is analyzed and simulated.The simulation results show that the proposed method can effectively improve the quality of the micro-grid power and eliminate the influence of the harmonics in the micro-network,and it has a certain reference and engineering pratical significance for the future electric vehicle access to micro-grid.