植基於混合通訊架構之電動船電池管理系統開發

BATTERY MANAGEMENT SYSTEM DEVELOPMENT FOR AN ELECTRIC MARINE VEHICLE BASED ON HYBRID COMMUNICATION PROTOCOLS

電動船馬達所需的驅動電壓高必須由多顆鋰離子電芯串聯成電池組，而為了避免電芯過充、過放、電芯電壓不一致等問題，需要完善的電池管理系統以確保電池組的安全與使用壽命，多電芯串聯電池組的電池管理系統考量微控制器的腳位有限與線路配置通常需要多模組串聯的電池管理系統，而且採取相同通訊協定的主從管理架構。缺乏可靠且效率高的通訊系統，電池管理系統與相對應電動載具將無法正常運作並有災難性的意外可能發生。本研究開發一適用於多模組串聯的鋰鐵磷電池管理系統並植基於一創新的混合通訊架構，此電池管理系統由24V模組電池管理系統（slave）與96V主控制板（master）的主從拓樸所組成，24V模組電池管理系統管理8顆鋰鐵磷電芯，96V主控制板則與4個24V模組電池板進行資料與命令的雙向通訊，執行電池系統的管理任務，將此系統應用於一自製之陸上電動載具上進行系統評估與測試，道路實測之實驗數據發現此電池管理系統性能良好，電池組數據量測與估測皆非常準確，通訊穩定度與可靠度高。 Electric marine vehicles demand high performance motors working at high voltages. High voltage lithium batteries are constructed by high number of lithium battery cells connected in series. However, lithium batteries require advanced battery management systems (BMS) to prevent cells out of electrochemical limits; balance state of charges among cells in series; and estimate battery state of charge. Appropriate BMS is instrumental of safety and longevity for lithium battery systems. Considering finite number limitation of pins for any micro controller units (MCU) and also complex harness resulted from connecting large number of battery cells in one module, advanced BMS usually is based on multiple battery module topology. Same communication protocols are usually used within and outside the BMS system. Reliable and efficient communication within and outside the BMS is critical for safe operation of the electrical vehicle. This study develops an advanced BMS for multiple lithium battery modules connected in series based on an innovative hybrid communication strategy. The BMS is based on a 96 V master and 24 V slave topology design. Each 24 V battery module with 8 cells connected in series is managed by a module BMS, which serves as a slave, and 96 V main control board, which is a master, coordinates two way communication between master and slaves and execute battery management actions. This BMS is applied to a land-based electrical vehicle to evaluate the BMS performance. Road tests show good performance of the BMS resulting from the reliable and efficient hybrid communication strategy.