Research Of The Intelligent Photovoltaic Combiner System Based On ARM Cortex-M4

With the solar photovoltaic technology become more and more nature, the requirements of intelligent and cyber photovoltaic power generation system are increased. Intelligent and cyber photovoltaic power generation system means not only convenient management, it is also beneficial to improve the efficiency of power generation and enhance the safety factor of power generation systems.This paper summarized the demand and the development situation of solar photovoltaic power generation, analysis was made on the problems of photovoltaic power generation technology, management and safety issues. The PV combimer box is introduced in the status, function and characteristics of photovoltaic power generation. The development status of combimer box at home and abroad was discussesed, in view of the present combimer box is common with processing power is not strong, poor human-computer interaction, backward communication mode, safety performance is not higher shortcomings, an improved convergence of photovoltaic system is of better solutions.In order to solve the key problems of the PV combimer box such as control technology, current detection technology, voltage detection technology and network communication technology, this paper has carried out the following work:the selection of processor, with more advanced ARM Cortex-M4architecture chip MK60DN512as the host controller, it provides a strong processing capacity for the control system. On the voltage and current detection device selection, selected the high precision hall voltaege sensor HBV05A3.3for voltage measurements, selected the high precision closed loop hall current sensor HBC06LTS3.3for current measurement, and finally designed the voltage and current detecting circuit. The TFTLCD chosen as the monitor, it effectively improved the human-computer interaction interface. To realize the network remote monitoring system, Ethernet communication module for system was designed.In view of the combimer box’s outdoor working environment, we designed the hardware security protection for the system. The over-current protection circuit was designed in the input and a DC circuit breaker, a lightning protection device ware designed in the output. The protection device effectively prevent the system under the conditions of overload, short circuit, a lightning strike damage to ensure that the system is stable, reliable and safty work.Each module of the combimer box has been carried out to experiments test. Error analyses of both hall current sensor and voltage sensor measurement data was did. The repeatability on average standard deviation and hysterisis error were calculated. Using the least squares method fitting the work-curve of the two types of sensors. A linear calibration method was proposed on the software and used n times average filtering and median filtering to calculate the precision of the system. Communications test was done to the Ethernet module and result showed that the network communication function is realized.In this paper, the convergence of photovoltaic system has carried on the overall test and the test results show that the system performance is good. It has positive significance to promote the upgrading of the convergence of photovoltaic system and the intelligent of solar photovoltaic power generation system.