Study on an Advanced Low Voltage Ride-Through Control Strategy of Energy Router

With the drastic growth of the energy internet in recent years, the energy router, an important energy hub, has seen wide application and unprecedented value due to its many functions such as energy transmission and coordination management. However, the energy router's ability to cope with the grid voltage sag is critical to its stable operation. This paper presents an advanced low voltage ride-through (LVRT) control strategy for the energy router when the symmetrical grid voltage sag occurs. The presented LVRT strategy can assist in voltage recovery and active power maintenance. When detecting a voltage sag, the inner loop regulator is directly controlled which contributes to the amelioration of the response speed as the outer loop regulator is disconnected. Voltage sags of different severities require different reactive and active power injections to support the voltage recovery and reduce the impact on the energy router's power delivery. Simulation results confirm the effectiveness of the presented LVRT strategy.