Energy Feedback High-capacity High-frequency Transformer Test Platform for Typical Service Condition
The operating conditions of high-capacity high-frequency transformers are complex,and the waveforms of port voltage and current are variable.It is difficult to test and evaluate the performance of transformers under typical service conditions.Therefore,a high-capacity high-frequency transformer test platform is proposed,which consists of a twelve-pulse controllable rectifier circuit,a bidirectional DC-DC converter BDC1,and a bidirectional DC-DC converter BDC2.BDC1 generates high-frequency,high amplitude,and adjustable duty cycle high-voltage square waves at the transformer port through multiple module series combinations.In addition,a control method is proposed to achieve multi-ple dv/dt outputs by adjusting the phase shift angle between modules,which is used for simulating typical service conditions of high capacity high-frequency transformers.BDC2 is used to achieve energy feedback,significantly reducing the energy consumption during the operation of the test platform and reducing the demands for power supply capacity of the power grid.A 1.5 MW simulation platform consisted of 6 modules is built through PSIM simulation and the tested high-frequency transformer can achieve high-frequency square wave output of 6 kV/20 kHz and stepped wave output of 1 kV,laying a theoretical foundation for subsequent experimental platform construction.