摘要
大容量高频变压器结构紧凑,工作频率为数百Hz到几十kHz,工作波形为方波等非正弦的特殊激励波形。高频变压器电磁、结构、声等多场耦合紧密,运行时出现严重的振动与噪声问题,对高频变压器振动与噪声特性进行精细分析对于其减振降噪具有重要意义。为此,该文首先建立高频变压器电磁场-结构力场-声场3维仿真求解模型,明确各物理场的载荷传递过程以及电磁和力学性能参数;然后,采用有限元法得到不同电压激励下变压器铁芯表面时域振动波形与噪声频域特性,并定量评估了纳米晶切割铁芯对受力特性的影响程度;最后,对1台5 kHz/10 kVA高频变压器的振动和噪声进行试验测试,得到正弦和方波电压激励下铁芯振动和噪声数据。由仿真与试验结果可知,高频变压器铁芯拐角处振动较为剧烈且周围产生的噪声也较大;相比于正弦波激励,非正弦波激励下的振动不仅集中发生在2倍频,还存在许多高次谐波分量,同时各个频率段声压级明显增加;不同波形激励下测量点声压级相对误差均在10%以内,验证了仿真模型的准确性。
The large-capacity high-frequency transformer(HFT)has a compact structure,with a working frequency ranging from several hundred Hz to tens of kHz,and operates with special excitation waveforms such as square waves and other non-sinusoidal waveforms.The high-frequency transformer is characterized by coupling between multiple fields,including electromagnetic,structural,and acoustic fields,resulting in serious vibration and noise problems during operation.A detailed analysis of the vibration and noise characteristics of high-frequency transformers is of great significance for reducing noise.Therefore,this paper first establishes a three-dimensional simulation solving model of electromagnetic field+structural force field+acoustic field of HFT,and clarifies the load transfer process of each physical field as well as the electromagnetic and mechanical performance parameters.Then,the finite element method is used to obtain the time-domain vibration waveform and frequency-domain noise characteristics of the transformer core surface under different voltage excitations,and the influence of nanocrystalline cutting core on the mechanical characteristics is quantitatively evaluated.Finally,the vibration and noise of a 5 kHz/10 kVA HFT are tested,and the core vibration and noise data under sinusoidal and square wave voltage excitation are obtained.According to the simulation and experimental results,the vibration at the corner of the high-frequency transformer core is more severe and the noise generated around it is also larger.Compared with the sine wave excitation,the vibration under non-sinusoidal excitation not only concentratively occurs in the double frequency,but also has many higher harmonic components,and the sound pressure level in each frequency band increases significantly.The relative error of the sound pressure level at the measurement point is within 10%under different waveform excitation,which verifies the accuracy of the simulation model.
作者
陈彬
沈辰轩
刘洋
靳艳娇
万妮娜
CHEN Bin;SHEN Chenxuan;LIU Yang;JIN Yanjiao;WAN Nina(Hubei Transmission Line Engineering Technology Research Center,Three Gorges University,Yichang 443002,China;College of Electrical and New Energy,Three Gorges University,Yichang 443002,China;State Key Laboratory of Advanced Transmission Technology,China Electric Power Research Institute Co.,Ltd.,Beijing 102209,China;Yichang Electric Company,State Grid Hubei Electric Power Company,Yichang 443002,China)
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2024年第10期4459-4474,共16页
High Voltage Engineering
基金
国家自然科学基金(52107006)
湖北省自然科学基金(2021CFB149)。
关键词
电磁-结构-声场分析
振动噪声
高频变压器
电磁振动
频域特性
振动加速度
electromagnetic-structure-acoustic field analysis
vibration noise
high-frequency transformer
electromagnetic vibration
frequency domain characteristics
vibration acceleration
