Neutral current mitigation using controlled electric springs connected to microgrids within built environment

Modern buildings require complex planning and efficient energy management to lead them towards the ideal of self-sustainable buildings. The penetration of intermittent renewables as local sources for the building is a major step towards that ideal, but such energy conversions intensify the issues of instantaneous demand management and voltage stabilization. Also, the loads in a building can have their own complex, fast-changing operation strategies which further elevate the difficulty of these tasks. Unbalanced voltages are direct consequences of this scenario, which cause high neutral current that adversely affects the components of microgrid. This paper presents a method to mitigate neutral current in three phase systems using recently introduced concept of “Electric Springs”. The electric springs consist of fast acting passive devices controlled through power-electronic switches, connected to the building microgrid based on load classifications of critical and non-critical. The proposed method would result in better equipment safety and longevity of the critical building loads.