The invention provides an electric principle-based 
wind power plant cluster reactive 
power sharing method. The method comprises the following steps: calculating real-time 
voltage of hubs; calculating 
voltage difference of the hubs; calculating the reactive 
power demand quantity of the hubs; calculating equivalent electric impedance of the wind 
powder plant from the wind 
plant to the hubs according to regional tidal 
stream information and 
wind power plant access circuit parameters; calculating the reactive sharing quantity of the 
wind power plant; and sending a reactive adjusting command to a wind power plant 
monitoring system to enter the next control. In the method, the hub 
voltage in the wind power plant access region is used as a regulating object, the actual condition of the wind power plant access region is concerned, and local region operation information is utilized so that equivalence is performed to the impedance of a wind power plant power passing circuit according to the basic electric principle; the reactive power is optimized by using the minimum active 
power loss of the access region as a target to ensure that the 
power grid operation and economic benefit of reactivepower adjustment are concerned while the wind power plant cluster provides reactive power support, and the reactive power coordinating 
distribution control of the wind power plant cluster can be improved conveniently.