Development Of Small-Scale Photovoltaic Nickel-Hydrogen Energy Storage System

As the world's energy problems become increasingly prominent,people are constantly looking for energy available in nature.The development of photovoltaic power generation,wind power and other new energy is faster and faster,how these energy in green,low-carbon way to store has become the direction of world energy development.At the same time,with the increase in electric vehicle production,it will lead to increased power battery decommissioning,which will not only reduce the battery life cycle,and after the retirement of the batteries will cause environmental pollution.Therefore,this paper developed a photovoltaic energy storage system based on echelon power battery,which both from the environmental or social point of view has a high value.According to the function of the energy storage system,this paper has developed a small-scale photovoltaic energy storage system with the Ni-MH battery and the thin-film solar panel as the power generation device.The system includes the energy management system,and the DC/DC converter based on the Boost circuit is designed,thus realizing the whole process from power generation-energy storage and electricity consumption.The main works are as follows:For the energy storage battery part,the article uses decommissioned nickel-hydrogen battery pack,after the capacity test and full charge state of the voltage test.According to results,this paper adopts the clustering analysis method based on Euler distance to make sets of batteries.The voltage level is 48 V and the capacity is 40Ah.Second,for the system function,developed an energy management system based on Freescale MC9S12XEG128 microcontroller and power management chip LTC6803.The system hardware circuit design of the sampling module,the battery voltage,current and temperature of the three state of the sampling function can be achieved;At the same time,from the view of battery life and improving battery utilization,the battery balance circuit is designed.For the photovoltaic power generation part,this paper uses thin-film solar panels,and its light test,record the curve and analyze the maximum power point.According to the results,the maximum power point tracking algorithm based on climbing method is adopted,and the maximum power point tracking of the system is realized by adjusting the voltage of PV panel.The hardware circuit of this part designed MOSFET driver circuit,relay control circuit and photovoltaic panel voltage sampling circuit.The software part is written using the embedded microprocessor development software Code Warrior IDE.The software part can be divided into charge control,battery condition monitoring and electricity control three parts.The charge control mainly includes the DC/DC circuit control of the photovoltaic power generation system.It is worth noting that the PV system needs to maximize the energy transmission.The software part designs the maximum power point tracking algorithm.The battery condition monitoring part mainly includes real-time acquisition and processing of the battery state information,the estimation of the battery SoC,and the power consumption control unit determines the load usage based on the power generation side and the current state of the battery.