A Novel Multifunctional Energy Storage System in Industrial Distribution Network

In order to meet the increasing safety demands from coal industry and mining company, a lead acid and lithium iron phosphate(LFP) battery energy storage based megawatt level multifunctional emergency power station is designed and developed for a famous coal mine in Inner Mongolia, China. The major function of system is: when the local power grid works normally, the developed system will play the reactive power compensation function instead of traditional static capacitor; when the local grid occurs failure, the energy storage based emergency power station will provides stable power to the extremely critical loads of coal mine for at least 30min. Besides, the proposed energy storage system also can play the ‘peak shaving’ and distributed new energy generation smoothing according to the customer requirement. The This paper firstly describes the system integration design and major functions; secondly introduce the power conversion system design and NI software/hardware based central control unit; thirdly analyzes the solutions for increasing system lifetime including novel harmonics control for charging & discharging and battery regular online maintenance strategy; finally provides the simulation and test results which demonstrate the correctness of system design, software/hardware development and integration. The business value evaluation shows the high market potential of the proposed system in China and worldwide. 