Abstract: The main type of current wind power generation units is the doublefed unit. The stator and the rotor of this type unit can feed out energy simultaneously; and this feature determines that the design of the main circuit and the device type selection for this type unit are more complex than that of other asynchronous or synchronous machine unit. The working principle of the main circuit of doublefed wind power generation unit was analyzed, and taking a 1.5MW doublefed unit as studying object, the typical design of the main circuit structure was given, and the electric circuit parameters of various parts of the main circuit were analyzed. Based on this, the device type selection scheme of various parts of the main circuit was recommended. The scheme was adopted in practical product manufacturing, and the desired effect was obtained.

Key words: wind power generation, double feed unit, main circuit, device type selection