An Online Condition Monitoring Method of Single-Phase PWM Rectifier Based on Digital Twin

To monitor the inductance, resistance, dc-link capacitance and load status of single-phase two-level PWM rectifier, a digital twin based online status monitoring method is presented in this paper. By analyzing the external characteristics of the circuit through voltage and current sensors, the proposed method can real-time monitor the operating state of the rectifier without interfering the normal operating of the circuit. Firstly, the mathematical model of the adopted rectifier is built, including the main circuit model and control scheme, discretize them with Runge–kutta. Then, the particle swarm optimization (PSO) algorithm is applied to updates the parameters of the digital model in real time by comparing the data measured by the sensor with the data of the digital model, which can optimize the established digital model, so that the digital model can accurately reflect the real-time status of physical system. Finally, the proposed method is verified in Matlab/Simulink, the simulation results verify the correctness and validity of the proposed method.