Abstract: At present the mainstream of doubly-fed induction generators（DFIG）control mode is the current

source type vector control mode，which is lack of independent of frequency and voltage support ability，but the voltage source type virtual synchronous machine control method can solve the shortcomings. In order to meet the

requirements of the grid work under different scenarios，it is necessary to study the control of the DFIG mode

switches. A control strategy for smooth switch between voltage source and current source in dual-mode operation of

DFIG was proposed. Firstly，by analyzing the above two control modes，the control mode switching problem was

transformed into the problem of ensuring the current inner loop input and phase smooth switching. On this basis，the phase and current instructions could be smoothly switched during the control mode switching through the joint action of controller state following and numerical retarder，and the current shock and power fluctuation during the operation mode switching of DFIG were suppressed. Finally，the effectiveness of the proposed control strategy was verified by theoretical analysis and simulation results.

      Key words: doubly-fed induction generators（DFIG）；smooth switching；dual-mode；virtual synchronous

generator（VSG）control；vector control