新型光伏锂电无均衡管理储能发电系统

Novel PV/Li-Ion Energy Storage System Based on Non-balancing Cell Management

提出了一种新型光伏锂电储能系统拓扑结构.在该结构中,光伏电池与锂离子电池单体之间通过控制单元实现能量耦合,通过光伏电池与锂离子电池单体之间的结构耦合,实现锂离子电池的无均衡管理(NBCM).对该拓扑结构进行了仿真和实验验证,实验结果表明,该光伏锂电储能模组能够在以欠压浮充为投切判据的控制单元工作模式下,实现光伏电池近似MPPT工作的同时,能有效地对锂离子电池进行充放电;与肖特基二极管近似直连相比,通过MOSFET以近似直连的方式耦合选定工作电压的30 W光伏电池与锂离子电池能够提升模组能量效率约8%,在独立运行和并网运行光伏储能发电系统中均可应用.

A novel topology of an energy storage system composed of PV panels and lithium-ion batteries was presented. For the individual module of the proposed system,the energy coupling between the photovoltaic panel and lithium-ion cell is achieved with the designed control unit.Besides,with the structural coupling of the photovoltaic panel and lithium-ion cell of the PV /Li-ion module,the non-balancing cell management（ NBCM） for the lithium-ion cell is realized. The proposed system was verified by simulation and experiments. It is shown that,in the proposed PV /Liion module,with the low-voltage floating charging criteria,the approximate MPPT（ maximum power point tracking） control was accomplished with the charge-discharge of the lithium-ion cell. In comparison with the schottky diode connection,the operation efficiency of the PV /Li-ion module is increased by about 8% when there is a nearly direct connection between the lithium-ion cell and the30 W PV panel with nearly no intervening electronics（ just MOSFETs,metallic oxide semiconductor field effect transistor）. The novel topology of the NBCM PV /Li-ion system can be applied both in stand-alone photovoltaic-battery systems and in grid-connected photovoltaic power plants.