Grid-connected electrolysers can not only convert electricity into hydrogen for the use in other sectors, but also increase the operational flexibility of electrical networks by providing demand side management. This paper develops a scheduling model to optimise day-ahead electricity consumptions of electrolysers that are connected to a distribution network. The network status and unit outputs across the complete time horizon are simulated and coupled by the dynamic optimal power flow, which then optimises electrolyser imports to reduce renewable generation curtailments. Furthermore, the requirement on hydrogen production and the specific operational limits of electrolysers are respected by the scheduling model. The scheduling model is tested based on a 1 MW electrolyser system within a distribution network. The simulation results indicate that the electrolyser system is scheduled to effectively respond to renewable curtailments while meeting the hydrogen production requirement. In addition, the coordination of multiple electrolyser units within a system extends the suitable LF range of the system, which is more flexible to increase the use of renewable generation.