This article proposes a control strategy for flexible participation of energy storage systems in power grid peak shaving, in response to the severe problems faced by high penetration areas of new energy, such as wind and solar power curtailment, peak shaving, and rotating backup configuration. This strategy considers the coordination and control of fast and slow peak shaving resources for battery state of charge. While ensuring the stability of system operations, it prioritizes the voluntary participation of energy storage with faster response speed in grid peak shaving. At the same time, it reasonably arranges the adjustment timing coordination of fast and slow speed units to improve the quality of system peak shaving services.