An Adaptive Reverse Droop Control for Coordinated Power Sharing Strategy of GFM and GFL Inverters

The power sharing and circulation problems of new energy station deserve attention because of the inevitable parameter errors, but the unified power sharing control of grid-forming (GFM) and grid-following (GFL) inverters is lacking. Taking photovoltaic (PV) GFL inverters as an example, the necessity of equal active and reactive power sharing of GFL and GFM inverters is discussed in this paper. After analyzing the specific influencing factors of circulation, a circulation suppression strategy combining virtual impedance and a novel adaptive reverse droop control is adopted. The method proposed in this paper makes GFL inverters also participate in the power regulation process, and can be applied uniformly with the circulation control strategy of GFM inverters, which improves the power sharing accuracy of the whole parallel system and reduces the difficulty of the control system design. Simulation results are used to illustrate the accuracy of the established model and the correctness of the conclusions obtained.