Photovoltaic energy storage droop control

Is droop control a good strategy for a microgrid energy storage system?

The DC bus voltage fluctuation amplitude is small and has strong recovery ability. The SoC can still converge orderly under communication delay. To solve the problems of SoC imbalance, uneven current distribution and DC bus voltage deviation in microgrid energy storage system, an improved adaptive droop control strategy is proposed in this paper.

What is adaptive droop SoC balancing controller (ADSB)?

In the primary control layer, a novel adaptive droop SoC balancing controller (ADSB) is designed to realize the adaptive change of droop coefficient by establishing the real-time relationship between SoC value and droop coefficient, so as to promote the SoC balance among distributed energy storage units (DESUs).

What is a Droop coefficient balancing control strategy?

An innovative SoC balancing control strategy is designed. This method establishes the real-time relationship between SoC and the corresponding droop coefficient, and introduces the energy storage capacity value to adjust the droop coefficient, thus promoting the SoC balance among DESUs.

Does droop control affect ESS stability of DC microgrids?

System stability analysis For DC microgrids containing DESUs, droop control will affect the stability of system operation. In this paper, two parallel DESUs with equal capacity are taken as examples to analyze the ESS stability of microgrid under the proposed control strategy.

What is the rated capacity of a solar PV system?

The initial SoC values of the three DESUs are set at 50%, 55% and 60% respectively, and the rated capacity is 0.3 Ah. The whole simulation process is divided into four stages, in which the output power of the PV system is always maintained at 9.2 kW, and the load power changes three times. In the first stage (0 to 15 s), the load power is 7.5 kW.

What is the output power of a solar PV system?

In the first stage (0 to 30 s), the PV system output power is 8.5 kW, ESS discharge. In the second stage (30 to 60 s), the PV system output power becomes 12 kW, and the ESS is charged. The simulation results of low SoC level condition are shown in Fig. 20 (d), (e), (f). Before 20 s of the first stage, all DESUs are in discharge state.