Characteristics Analysis of the Operational Parameters of a Novel Rectifier Transformer With Filters

A type of rectifier transformer with its corresponding filtering system consists of grid side winding,valve side winding,and individual filtering winding with filters bank.Its special filtering branch can restrain the harmonic currents,compensate the reactive power and improve the operational performance of the transformer.Firstly,a detailed derivation was implemented to build a harmonic current suppression mathematical model based on harmonic suppression factor for analyzing the harmonic transmission.Secondly,a relationship between grid side current and load current was built to study the characteristics of the reactive compensation and analyze the corresponding operational parameters.Thirdly,a relationship between the valve side and the grid side voltage was deduced to study the effect of the filters on the valve side voltage.Theoretical analysis showed that the new rectifier transformer with its corresponding filters could effectively suppress the harmonic currents,reduce the grid side current and apparent power,enhance the grid side power factor and the load side voltage.Finally,field tests for the new rectifier transformer in an industrial DC system were performed,they verified the correctness of the theoretical analysis.The field tests comprehensively reveal the ability of the new rectifier transformer in improving the operating characteristics of the rectifying system.The deduced mathematical models will contribute to further research of the new system on energy conservation and noise reduction.