Abstract: The independent operation of hydropower, photovoltaic (PV) and energy storage stations is constrained by transmission channel capacity, leading to frequent curtailment of water and PV power, which limits the clean energy absorption capacity of power grids. To address such an issue, this paper describes an optimal scheduling method for hydro-PV-storage complementary systems based on the Asynchronous Advantage Actor-Critic (A3C) algorithm, which is applicable to large-scale hydro-PV-storage coordinated operation scenarios. First, an operational scenario of hydro-PV-storage stations is constructed, and an optimal scheduling model is built based on the short-term versus medium- and long-term complementary guidance mechanism. Then, for a hydro-PV-storage complementary system, we transform its optimal scheduling problem into a Markov decision process, and achieve efficient strategy exploration and learning via deep reinforcement learning algorithms. Finally, we validate the method through application to such a system in the Yarkant River basin, Xinjiang. Results show the A3C algorithm stably converges to high reward values and improves system-absorbed electricity significantly with its computational cost notably lower than other algorithms, demonstrating its promising practical application value.

Key words: hydro-photovoltaic-storage system, complementary mechanism, deep reinforcement learning, Yarkant River basin, asynchronous advantage actor-critic algorithm, Markov decision process