Device and method for testing operation capability of voltage source of wind turbine generator

The invention provides a device and a method for testing the operation capability of a voltage source of a wind turbine generator. The device comprises a grid-connected switch, line impedance simulation and load simulation, the line impedance simulation and the grid-connected switch are connected in series to form a branch circuit, and the branch circuit is connected in series between a box transformer high-voltage side and a grid-connected point of the tested wind turbine generator set and used for testing the weak power grid adaptability of the wind turbine generator set; the load simulation is connected in parallel to the box transformer high-voltage side of the tested wind turbine generator set and is used for testing the off-grid operation capability and the black start capability of the wind turbine generator set; wherein the operation capability of the voltage source of the wind turbine generator comprises weak power grid adaptation capability, off-grid operation capability and black-start capability,