A phase feedforward based virtual synchronous generator control scheme

Abstract

Virtual Synchronous Generator (VSG) is an important method to solve the frequency stability issue of the power electronic based power grid by use of virtual inertia control. However, the virtual inertia may cause power oscillation. Although the traditional VSG control scheme can damp the oscillation well by increasing the damping ratio, the system response becomes sluggish unexpectedly. Meanwhile, the damping of traditional VSG scheme changes the droop coefficient and thus causes the steady-state error in proportion to the damping coefficient. To solve this problem, this paper develops a novel phase feedforward based VSG control scheme, which can damp the power oscillation well through the phase feedforward channel. Furthermore, this method possesses significantly improved transient performance and does not produce the steady-state error. Comparison is drawn between the traditional VSG scheme and the proposed VSG scheme, which proves that the proposed VSG scheme has a marked improvement over the traditional VSG scheme in both dynamic and steady-state response characteristics of active power and the system stability. Both the simulation and experimental results validate the effectiveness of the proposed method.