Brushless doubly-fed induction generator(BDFIG)enjoys bright potential in the fields of wind energy conversion. In order to calculate the reactive power capability of a kind of cascaded dual-stator BDFIG(DS-BDFIG)

an analytical approach is provided. Based on the steady-state model of the DS-BDFIG under grid-connected operation

the power flow and adjustment mechanism of the system are firstly analyzed. Considering the current restraint and reactive power capacity of the grid side converter

the analytical arithmetic of reactive power capability for the DS-BDFIG system is then deduced. Moreover

the effect of copper loss and saturation on reactive power capability are taken into consideration to adjust the output curves of active power and reactive power. By analysis and simulation of an actual 10 kW DS-BDFIG

it is shown that the reactive power limit of the DS-BDFIG considering multi-contraints approaches to reality.