Charging Control And Power Quality Monitoring System For Electric Vehicle Charging Station

In recent years, as the government vigorously support the development of electric vehicle industry, the electric vehicle industry has been in rapid development of large span, which leads to large-scale construction of electric vehicle charging station, the important electric vehicle service infrastructure. Charging to the electric vehicle safely put forward higher requirements of the reliability and automation of the vehicle charging equipment for charging station. In addition, as the electric vehicle charging station has become an important part of modern intelligent electric system, the access of charging equipment will certainly have an impact on the existing transmission and distribution of the system. Therefore, automatic charging control system and multiparameter monitoring of the power quality has become the focus of the electric vehicle related fields, and the development of the equipment of the system and the monitoring has also become the essential section in the design of electric vehicle charging station and has great significance to the development of smart grid and the electric vehicle industry.Based on the analysis of current situation and trend of charging control system and power quality monitoring of electric vehicle charging stations in domestic and abroad, this thesis proposes the concept of measuring the qualification of battery energy storage and the parameters of power grid simultaneously which diversifies the function of the device. This topic comes from the key technology project of "Charging Control and Power Quality Monitoring System for Electric Vehicle Charging Station", which is supported by Power Supply Company of Datong in Shanxi Province.On the basis of the research of network communication technology, data acquisition system and sensor technology, this paper develops a set of charging control and power quality monitoring system for electric vehicle charging station, which puts ARM technology and sensor technology as the core.The detailed work of this topic is described in following section:(1) Analysis of the current development situation of the control of electric vehicle charging stations and the system of power quality monitoring in domestic and abroad has been presented in this thesis, attached with the elaboration of the great significance made by charging control and power quality monitoring system of the charging station in the development of electric vehicle industry.(2) According to the comparisons of merits and drawbacks of various types of existing electric vehicle batteries and different SOC estimation models. Besides the practicability and pertinence of the system, we deduce a control scheme based on the charging battery SOC estimation. A new model to estimate the Ah-EMF has been designed which will be a solution to ill accuracy of power battery charging parameter monitoring and realize the control of charging equipment.(3) Design of hardware circuits of the monitoring system including choice of part of components, microprocessor, net communication, sensor data acquisition, JTAG interface and design of power management circuit. This thesis introduced the whole design frame of the system and the background of the technology used in it. All of these provide a reliable hardware platform for the safe operation of the control software.(4) Completion of the design of the monitoring system software and detailed elaboration of respective design process of key modules subroutine. The test of the whole system followed the successful test of hardware and software. From the comparison with the calibration value, it confirmed that the monitoring function of the system was effective and accuracy. High-order harmonic measurement accuracy could be improved.