1. A power system comprising: a system load; and a plurality of power supplies connected in parallel with each other and connected to the system load for respectively outputting a load current to the system load, wherein each power supply comprising: an active current sharing circuit configured to enter an operation mode or a shutdown mode depending on whether the load current is higher than a first current set point; and a droop current sharing circuit configured to enter an operation mode or a shutdown mode depending on whether the load current is higher than a second current set point; wherein each power supply is configured to output an equal share of the load current by an active current sharing technique and a droop current sharing technique; wherein the second current set point is higher than the first current set point.