Power Factor-driven Scheduling Strategies on Power-to-Hydrogen Systems with Two Typical Converters

The large-scale power-to-hydrogen (P2H) systems formed by multi-stack is a potentially powerful peak shaving resource of power systems. However, as P2H systems integrate into the grid, the power factor (PF) that the grid code will limit is a lack of consideration in existing studies. This paper fills the gap in capturing and comparing PF characteristics and PF-constrained scheduling strategies on P2H systems with two typical industrial power converter interfaces (PCI), i.e., thyristor and insulated-gate bipolar transistor (IGBT)-based. First, this paper proposes a general PF modelling methodology of P2H systems with unified current and temperature operation variables. Then, a scheduling model is constructed to determine the optimal strategy under the PF constraint and production target. Analysis of a two-stack P2H system reveals an intrinsic mechanism of PF characteristics under different operation conditions. On this basis, P2H systems with two PCIs present opposite PF tendencies within the operation ranges, and further indicates that the thyristorbased PCI needs to trade-off PF and production. Furthermore, scheduling strategies corresponding to two typical PCIs are quantitatively evaluated to verify the comprehensive advantages of IGBT-based PCI.