Research On Charge-discharge Mechanism And Monitoring System Of Distributed Photovoltaic Lithium Batteries

In the creation of smart cities,lighting and monitoring equipment that powered by solar energy that are used on a large scale.How to make full use of the limited light time and the limited storage capacity of lithium batteries to obtain a longer effective power supply time for the system that is the main problem in the solar power system.At the same time,how to reduce the labor cost of outdoor equipment operating status monitoring and fault detection that is also a problem worthy of attention.In order to achieve the maximum energy storage of the lithium batteries in the limited light time and reduce the labor cost of equipment detection and maintenance,a kind of lithium batteries polling charge and discharge strategy which is proposed,and a radio frequency communication which based wireless monitoring system.The poll charge and discharge strategy that ensures that a solar panel in a limited light time to five groups of lithium batteries to take turns charging to obtain maximum energy storage.While the lithium batteries continue to power the equipment,which achieves rotating charging and rotating discharge,which ensures that the equipment to obtain the maximum power supply time.The wireless detection system that mainly includes the FC-209S wireless data transmission module for wireless data transmission through the serial port and the host computer that built by the MCGS monitoring and management platform.It mainly realizes that the detection of the operating parameters and status of multiple equipment in the area,which provides maintenance data.Including the operating parameters of the five lithium batteryies and solar panels in each device,and real-time operating parameters of 200 devices that can be obtained.The whole system hardware design mainly includes the solar maximum power point tracking(MPPT)charging circuit,the STM32 control circuit that implements the lithium battery polling charge and discharge strategy,the switching circuit,and the radio frequency wireless transmission circuit.The welding of the hardware circuit that is completed,and the polling charge and discharge control strategy,serial port output,and host computer wireless communication monitoring program which are written.The system test that was carried out,the test content that mainly included the state test of the solar MPPT charging circuit,the polling charge and discharge strategy test,the serial port circuit test,and the comprehensive function test of the host computer monitoring.The test results show that the system has realized the maximum power output of solar energy,the polling charging and discharging strategy of the lithium batteries of a single device,the serial output of the status information of a single device,and the effective monitoring of multiple devices by the host computer.The performance of the system meets the needs of users and the design goal that are reached.