Li Hongjia

The cornerstone of energy internet: research and practice of distributed energy storage technology

Due to the distribution and the fluctuation of energy generation, and random energy demands, energy flows in energy internet have inherent uncertainties and randomness. Therefore, distributed energy storage system is the fundamental component of energy internet, which can effectively smooth uncertainty of energy flow, and support spatial-temporal reallocation of originally distributed and fluctuant energy. Battery, as one of the most important energy storage carrier, has many non-linear physical effects, e.g., self-recovery effect, rate capacity effect, and individual physical differences among different cells. Therefore, effective battery network management determines whether distributed battery storage system could work well. However, from viewpoint of battery management, battery network, which contains many inter-dependent and non-linearly featured elements, is a complex system, which brings great challenges to battery network management. Therefore, based on our previous technical achievements, we propose a set of methods and techniques on battery network management: 1) modeling and state parameters estimation of battery network; 2) fuzzy measure based features extraction and fast calculation of battery network; 3) adaptive dynamic programming based battery network optimization. Finally, inspired by the core idea of energy internet, we introduce the distributed energy storage architecture, and its optimal management methods to the energy supply and backup system of data centers, and describe our developed prototype system. Our work could provide theoretical and technical guidelines to applications of energy internet and distributed energy storage system.