Flexible dispatching method for park-level integrated energy systems considering energy cascade utilization

The complex energy conversion and the volatility of renewable energy/load bring great challenges to the operation of the park-level integrated energy system (PIES). To overcome this challenge, this paper proposes a multi-timescale flexible dispatching method to fully exploit the flexibility of PIES in the energy cascade utilization mode. The cascade utilization model for energy flow is firstly established to analyse the coupling and complementary of heterogeneous energy. On this basis, the supply-demand general equations of multi-energy flexibility are proposed, which accurately quantify the ability to cope with uncertainty through mutual flexibility. Through coordinated complementation and mutual exchange of multi-grade flexibility, the system realizes the suppression of random power fluctuations. The scheduling model includes day-ahead dispatch and intraday multi-time scale dispatch, which can satisfy the adjustment speed requirements of different energy. Numerical results demonstrate that the proposed method effectively enhances the flexibility and economy of system operation. The flexible demand for energy of all grades can be satisfied. Compared with the flexible dispatch in the triple energy supply structure, the operating cost is reduced by 9.07%.