WANG Zhengnan, ZHANG Xinhui, PENG Ke, et al. SOC Balanced Power Distribution Strategy Under the Control of Virtual DC Generator[J]. 2021, 47(8): 2923-2931.
WANG Zhengnan, ZHANG Xinhui, PENG Ke, et al. SOC Balanced Power Distribution Strategy Under the Control of Virtual DC Generator[J]. 2021, 47(8): 2923-2931.DOI:
The DC microgrid in which factors such as frequency and reactive power do not need to be considered is conducive to the access of new energy. However
the inertia of the DC microgrid connected to a large number of power electronic converters is low
which will affect the stable operation of the microgrid in severe cases. In order to increase the inertia of the system
there are many research results on the control strategy of the two-way DC/DC converter virtual DC generator on the energy storage side
but there are few research results on the power distribution of multiple virtual DC generators operating in parallel. In order to solve the problem that the batteries with a low initial state of charge may prematurely exit the discharge due to unreasonable power distribution among the batteries
we proposed a state-of-charge balanced power distribution strategy in which the state-of-charge is taken as a variable. This strategy is suitable for multiple virtual DC power generation with different capacities. The multi-power DC microgrid with photovoltaic units and energy storage devices was constructed
and the system small-signal model was established. The impedance ratio criterion was used to analyze the small-signal stability of the system. Finally
the PSCAD/EMTDC was used for simulation verification.The results show that the power distribution method proposed in the article can achieve the effect of balancing the state-of-charge between the batteries
and solve the problem that the battery with a lower initial state of charge prematurely exits discharge.