Through non-intrusive load monitoring technology， a more detailed understanding of the electricity consumption information of residents at various time periods can be obtained， This can help us to develop a reasonable electricity consumption plan for scientific electricity use. The focus of non-intrusive load monitoring technology is the detection of transient events. The proposed Hilbert vibration decomposition （HVD） algorithm detects the transient events in the sudden change of electrical parameters such as power and current when the electrical equipment is turned on. Compared with the double-sliding window CUSUM change point detection algorithm， the HVD algorithm load detection does not need to set a threshold， so the possibility of missed and false detection is greatly reduced. The corresponding circuit model is built by MATLAB / Simulink simulation software， and the simulation analysis shows that the HVD algorithm can effectively identify transient events.