PROJECT TITLE :

Modeling and Damping Control of Modular Multilevel Converter Based DC Grid - 2017

ABSTRACT:

A generic small-signal model of modular multilevel converter (MMC) based mostly DC grid is established and a DC virtual impedance damping management to suppress the resonance and instability is proposed. The averaged-price model (AVM) of MMC is used to derive the The´venin equivalent model of the converter from its DC facet using the facility-balancing principle considering the dynamics of section-locked loop (PLL) of the interconnected ac system. The only section p-typed line model is chosen to develop the nodal admittance equations of the DC network in s domain. The soundness criterion of the DC grid is given once establishing the generic linearization model. The key factors affecting the DC grid's stability are identified using the basis locus technique and participation factors analysis. The parameters and therefore the performances of the damping controller are designed and studied. Electromagnetic transient simulation model and RT-LAB real-time simulation are used to validate that the proposed damping control will suppress the instability of the DC grid and improve its operating performance.