能量回馈型大容量高频变压器典型服役工况试验平台

Energy Feedback High-capacity High-frequency Transformer Test Platform for Typical Service Condition

大容量高频变压器运行工况复杂,端口电压、电流波形多变,对其进行典型服役工况下的性能测试与评估比较困难。为此提出一种大容量高频变压器试验平台,其由十二脉波可控整流电路、双向DC-DC变换器BDC1、双向DC-DC变换器BDC2构成。BDC1通过多模块串联组合,在变压器端口产生高频、高幅值以及占空比可调的高压方波;此外,提出一种通过调节模块间的移相角实现多种dv/dt(电压上升率)输出的控制方法,用于大容量高频变压器典型服役工况模拟试验。BDC2用于实现能量回馈,显著减小试验平台运行时电能消耗,降低对电网供电容量的需求。在PSIM中搭建由6个模块组成的1.5 MW仿真平台,其待测高频变压器可以实现6 kV/20 kHz的高频方波输出与阶梯电压为1 kV的阶梯波输出,为后续试验平台搭建奠定理论基础。

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.