Abstract: To develop frequency regulation resources for intelligent buildings, an auxiliary frequency regulation system using a virtual synchronous generator（VSG） technology is proposed. The system provides power for the virtual synchronous generator with the power generation and energy storage systems of the intelligent building. It realizes the primary frequency regulation function of the intelligent building through a simulation of the synchronous generator active-frequency characteristics by applying VSG technology. The secondary frequency regulation function is performed by controlling the operation mode of the intelligent building and the output power of the virtual synchronous generator. It also integrates the auxiliary frequency regulation resources of the intelligent building and real-time visualization through intelligent switching and instrumentation technology. Finally, an auxiliary frequency regulation model for a single intelligent building is constructed, and six simulation experiments are designed. The experimental results show that the proposed system is stable and feasible, with inertia characteristics, and capable of providing inertia support power. The frequency regulation resource responds instantly and can realize stable output within 0.5 s, and when switching to islanded operation, stable operation can be realized within 1.5 s.