A wind turbine driven doubly fed induction generator（DFIG） model in both no-load cut in control mode and grid connecting control mode based on stator voltage orientation technique is introduced， and the difference in the two modes is analyzed. In order to keep the steady and dynamic performance in the two modes， a variable-parameter control strategy is proposed using different parameters for the rotor current controller. Design principles for the PI based current controller are given. The Bode diagram is used to design the parameters for the two modes. The result shows that the designed parameters are significantly different for the two modes. If the same parameters are used in the two control modes， it may lead to the system unstability or poor dynamic performance. Tests on a 30 kW wind turbine driven DFIG platform are implemented and the results demonstrate that the variable-parameter control strategy can ensure satisfactory steady and dynamic performance of the system in the two modes.