The invention discloses a control method for a
virtual synchronous generator capable of being adapted to imbalanced
power grid and load conditions. The control method comprises the following steps that 1) an active ring simulates the mechanical characteristics of a speed controller and a rotor to obtain an output positive sequence
voltage frequency and a phase position instruction; 2) a reactive ring simulates a n
excitation controller to obtain an output positive sequence
voltage amplitude value instruction; 3) a
voltage-control and virtual synchronous impedance ring simulates the electrical characteristics of a
stator; 4) positive and
negative sequence current rings carry out accurate tracking on the positive and
negative sequence current instructions respectively, and eliminates the
negative sequence current output; and 5) a modulation
signal is obtained by the combination of the positive and negative sequence current rings, and then the modulation
signal is subjected to PWM to obtain a
switching signal. Compared with the prior art, the output active
power fluctuation and frequency fluctuation caused by imbalance of the
power grid can be eliminated; and in addition, it is ensured that the output current of the
virtual synchronous generator is balanced constantly, so that overhigh electrical stress of a certain bridge arm of the
inverter can be avoided.