基于磁-热-流耦合的非晶合金变压器运行特征分析

非晶合金变压器绕组及其铁心一般采用矩形结构，其运行损耗引起的不平衡温升更易导致绕组绝缘劣化，影响供电可靠性。针对非晶合金变压器特殊的绕组结构，分析计算非晶合金变压器绕组温升，预测其热点温度，对矩形绕组结构变压器的设计优化和运行控制具有理论指导意义。本文基于三维磁-热-流多物理场耦合仿真计算和温升试验，以一台型号为SBH15-M-200/10的三相油浸式非晶合金配电变压器为研究对象，分析其额定负载下的运行特征，仿真计算各绕组的热点温度，并通过短路法温升试验对仿真结果的正确性进行了验证。研究表明：三维磁-热-流多物理场耦合计算非晶合金变压器绕组热点温度值与温升试验结果的相对误差小于5%，所研究非晶合金变压器绕组的热点温度出现在B相低压绕组的中上部，热点温度达到64.77℃

Analysis of the Operation Characteristics of an Amorphous Alloy Transformer Based on Magnetic-Thermal-Flow Coupling

The winding and core of amorphous alloy transformer generally adopt rectangular structure. The unbalanced tem-perature rise caused by operating loss is more likely to lead to winding insulation deterioration and affect the relia-bility of power supply. For the special winding structure of amorphous alloy transformer, the temperature rise of amorphous alloy transformer winding is analyzed and calculated, and the hot spot temperature is predicted, which has theoretical guiding significance for the design optimization and operation control of rectangular winding structure transformer. Based on the three-dimensional magnetic-thermal-flow multi-physics coupling simulation and temperature rise test, a three-phase oil-immersed amorphous alloy distribution transformer with SBH15-M-200 / 10 is taken as the research object. The operation characteristics under rated load are analyzed, and the hot spot temperature of each winding is simulated. The correctness of the simulation results is verified by short-circuit temperature rise test. The research shows that the relative error between the hot spot temperature of amorphous alloy transformer winding calculated by three-dimensional magnetic-thermal-flow multi-physical field coupling and the temperature rise test results is not more than 5 %. The hot spot temperature of amorphous alloy transformer winding studied appears in the middle and upper part of phase B low voltage winding, and the hot spot temperature reaches 64.77 °C.