High-speed trains generate a large amount of regenerative braking energy during regenerative braking

which cannot be simply ignored. Consideringthe influence of energy feedback on system imbalance in high-speed trains under various operating conditions

we proposed a cooperative unbalance compensation method（CUCM） for high-speed railway system to reduce the capacity and cost of power electronic compensation devices. In order to ensure that CUCM works well

two compensation principles were analyzed

namely

RPC principle and Steinmetz principle. Finally

based on the actual operation of high-speed trains

the capacity of CUCM was analyzed. The analysis and simulation results show that the two compensation methods have different implementation methods and compensation current expressions

but the compensation essence is the same and the cooperative compensation strategy should be adopted. Under the traction condition and energy feedback condition

the proposed CUCM can be used to effectively reduce the equipment cost while fully compensating the unbalanced current of the high-speed railway power system.