Trains in rail transit feature short station spacing and frequent start-stop operations. The traction motors switch to power generation mode during braking, producing regenerative electric energy that accounts for 20%–40% of the traction system energy consumption. Conventional methods mostly dissipate such energy via resistors with only a small portion fed back to the power grid, leading to massive energy waste. It also causes disturbing heat emission from resistors and grid voltage fluctuation.

As an electromechanical energy conversion and storage device, Yuankong maglev flywheel energy storage system boasts long service life and capability of frequent rapid charging and discharging, serving as an ideal solution for regenerative braking energy recovery in rail transit.

When trains brake or traction grid voltage exceeds the threshold, the system converts braking energy into kinetic energy and stores it in the flywheel.

When trains start up and accelerate, flywheel kinetic energy is converted into electric power and fed back to the traction power grid.

The system efficiently absorbs regenerative braking energy and restrains voltage fluctuation of the DC traction grid. It ensures stable electric braking and reduces wear of mechanical brake shoes. Meanwhile, it mitigates stray current issues at remote traction substations and cuts electrochemical corrosion on buried pipelines along the line, greatly improving operational stability and maintenance quality of the rail transit power supply system.