Neutral Point Information Based Overvoltage Damping Control Strategy for Ungrounding Power Distribution Network

In recent years, with the gradual promotion of the application of power electronic devices in the power grid, the typical problem of overvoltage in the distribution network can be effectively solved through fast-controlled flexible grounding devices. Existing research mostly takes the arc suppression coil grounding system as an example, but it has not clarified the influence between the flexible grounding device and the arc suppression coil. This paper takes the neutral point ungrounded system of the distribution network as an example, and proposes an information-based overvoltage damping control strategy based on the neutral overvoltage suppression mechanism of the flexible grounding device, the Bode diagram and the Nyquist criterion. A simulation is built with a 10kV distribution network model. The simulation results verify that the proposed method can effectively suppress both unbalanced overvoltage and ferromagnetic resonance in ungrounded system.