The Research On Parameter Measurement Of Supercapacitor Based On The Embedded System

The use of embedded technology, DSP and FPGA in supercapacitor testing field accelerates the development of the portable supercapacitor testing machines.Large current control technique which is based on power MOSFET has been almost shaped up.DSP and FPGA ,which are the pacemakers in digital field ,undoubtly replace the MCU and become the leading role in super capacitor testing system.Based on the above background, the study of the parameters of supercapacitors based on embedded testing system is accomplished in this issue.Based on a deep analysis of the structur of the supercapacitors , the method which is used to measure by large and constant current charge-discharge is raised.The MOSFET in parallel is used to enlarge current while the double integrals are used to achieve closed-loop control and improve the precision of the constant current . It also discusses the way to multiple MOSFET and has a brief state of the double integrals modules.According to the demand of the design,the hardware and software scheme which are based on the measurement of large and constant current charge-discharge of MOSFET are determined .It can realize the precise control of the measurement processing.What’s more, the voltage and current can be setted and it can meet numberable kinds of supercapacitors testings.In double integrals control, the inner integral cotrol can be realized by hardware,the accommodation process can be continuous and real-time. The Discharge process can be realized through reverse charge to supercapacitors in order to facilitate large constant current control and enhance the performance of the whole system. This project makes the most of the advantages between advanced technologies and mature principles. Control system based on DSP and FPGA is constructed,and a good hardware platform is built for process control and human-computer interaction. Real-time acquisition circuit is designed and built for parameters of testing process to achieve high accuracy for measurement information.External IO is managed uniformly by FPGA,which was easy to expand and improve system. A modular design approach is adopted in software design and each control module is managed separately, all of which are convenient to read and understand program and easy to update programs. Capacity and series resistance of supercapacitors are measured by this system. Because value of series resistance is tiny, the measures of anti-jamming are taken to meet precision. In testing capacity, the double closed-loop control is adopted to enhance current precision.