Short-term Optimal Scheduling of Cascade Hydropower-Photovoltaic Complementary System

Abstract

With the increasing penetration of photovoltaic (PV) generation, the uncertainty and intermittency of PV output pose significant challenges to renewable energy accommodation and secure power system operation. To improve the utilization of renewables in cascade hydropower (CHP)-PV complementary systems, this paper proposes a unit-level short-term optimal scheduling model. The objective is to maximize the expected absorbable energy under PV uncertainty, which is characterized using Latin hypercube sampling (LHS) and simultaneous backward reduction (SBR). A real complementary system in southwestern China is used for validation. Compared with a conventional CHP generation maximization strategy, the proposed model reduces curtailed renewable energy by 705.68 MWh and increases accommodated renewable energy by 686.93 MWh. The proposed method effectively enhances renewable energy accommodation capability and operational flexibility while ensuring system reliability.