Abstract：As an effective way to solve the low inertia problem of highly power electronic DC microgrids, virtual capacitance control needs to meet certain constraints in actual engineering applications to ensure the safe and reliable system operation. Accordingly, a virtual capacitance control method considering multiple constraintsis proposed, which synthetically considers some factors such as batteries’ state of charge, DC voltage change rate, instantaneous output power and output power per unit time of the converter. Firstly, the virtual capacitance calculation formula is improved by analyzing each constraint index. And the weights under different operating conditions are adjusted according to their importance. The obtained virtual capacitance is used to modify the inner loop current reference value in real time after formula conversion, which will change the battery power output, and improve long-term safe operation capability of the equipment as much as possible. Secondly, the small signal modeling analysis method is used to reveal the influence of main control parameters on the system stability, which provides a basis for selecting key parameter values. Finally, the effectiveness of proposed control method and correctness of stability analysis are verified by building the controller-level hardware-in-the-loop test platform.
张赟, 王毅, 孟建辉, 刘宝. 考虑多约束指标的直流微电网虚拟电容控制方法[J]. 电工技术学报, 2022, 37(zk1): 277-287.
Zhang Yun, Wang Yi, Meng Jianhui, Liu Bao. Virtual Capacitance Control Method of DC Microgrid Considering Multiple Constraints. Transactions of China Electrotechnical Society, 2022, 37(zk1): 277-287.
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