Research on the Application of High-Inertia Flywheel Energy Storage Condenser in High-Proportion Renewable Energy Power Systems

The large-scale integration of renewable energy grid-connected converters has exacerbated power coupling within power systems, precipitating simultaneous frequency and voltage dynamic stability issues in low-inertia grids. To address the urgent coordinated support requirements and existing technological challenges, this paper proposes a brushless doublyfed flywheel energy storage condenser system (BDFM-FESCS) and formulates a coordinated frequency-voltage support control strategy. This system utilizes partial-power converters to alleviate capacity contention between active and reactive power, while eliminating brushes and slip rings to improve high-speed operational reliability. Furthermore, the frequencyvoltage co-support control is developed from multiple dimensions: a fast-response power decoupling control is developed based on FESCS characteristics; a regulation logic is designed considering multiple operating states; and a distribution control for active and reactive power commands is proposed under transmission limits for precise power delivery.