For transformer putting into operation in power system

the magnetizing inrush current has adverse effect both on the electric devices and the power quality. A new principle of transformer non-inrush system is proposed which is based on SPWM technology. To realize the adjustment and control of the excitation voltage by controlling the models of high power electronics rectifier circuit

inverter

frequency conversion.First

applying a controllable excitation voltage in the low-voltage winding of the transformer

so the transformer core can smoothly and quickly establish a steady magnetic field. When the transformer is put into operation in the system

the voltage of transformer has the same amplitude and phase with the bus voltage

so that the synchronous closing is realized. Using the proposed method

the simulation model of suppression of inrush current is established

and the simulation result shows that the system can effectively inhibit the switching inrush current generation

and the feasibility of this method is verified.