Abstract:Different from AC distribution network, DC distribution network has low inertia characteristics. When the load of distribution network changes suddenly, DC bus voltage fluctuates greatly, and the quality of bus voltage faces great challenges. In order to solve the problem of low inertia of DC distribution network, super capacitor can be used to increase physical inertia or virtual capacitor (which needs to be provided by redundant capacity of converter configuration) to increase virtual inertia. The larger the capacitance, the higher the quality of power supply, but the higher the cost. However, the research on the suppression effect of capacitor on voltage sag is mainly qualitative analysis and lacks quantitative calculation. Therefore, the transient response of DC bus voltage under sudden load increase in radial DC distribution network is analyzed, and the mathematical relationship between the peak value of bus voltage sag and the DC side capacitance value of tie converter is obtained, which provides theoretical support for the design of system inertia parameters. Due to the complexity of the mathematical relation, a simplified method is designed to obtain the approximate algebraic relation for the convenience of engineering application. Finally, the calculation method of voltage sag peak value is verified by simulation and experiment.
唐欣, 蔡明君, 唐惟楚, 岳雨霏, 尹子晨, 彭超. 辐射型直流配电网母线电压跌落峰值的定量计算方法[J]. 电工技术学报, 2022, 37(12): 3108-3116.
Tang Xin, Cai Mingjun, Tang Weichu, Yue Yufei, Yin Zichen, Peng Chao. Quantitative Calculation Method of Bus Voltage Sag Peak Value in Radial DC Distribution Network. Transactions of China Electrotechnical Society, 2022, 37(12): 3108-3116.
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