提高开关电源工作频率——高频功率半导体器件：工作频率的提高可以提高功率密度。在相同的指标要求下，电路工作频率提高了，需要更高频率功率管，那么在电路中就可以使用更小的输出电感和滤波电容，这也就意味着，电感和电容的体积将大大减小，因此整个电路的体积和重量都将得到改善。但是我们必须要注意到随着开关频率的不断提高，开关元件和无源元件的损耗也增加，高频寄生参数以及高频EMI等新的问题也随之产生。随着工艺技术的提高，为进一步减小变压器的体积，可以采用平面变压器和压电变压器，可使高频功率变换器实现轻、小、薄和高功率密度。平面磁芯开发成功，可实现平面化的变压器设计。由于平面变压器要求磁芯、绕组是平面结构，所以应该采用多层PCB绕组。平面变压器的特点是高频，低造型，高度很小而工作频率很高。压电变压器利用压电陶瓷材料特有的“电压-振动”变换和“振动-电压”变换的性质传送能量，其等效电路如同一个串并联谐振电路，是功率变换领域的研究和应用的热点之一。料号E20/14/5-3E26E25/10/6-3E26E25/13/7-3E26-HME13/6/3-3E27E13/6/6-3E27E13/6/6-3E27-D1E13/7/4-3E27E16/8/5-3E27E19/8/5-3E27E19/8/9-3E27E20/10/6-3E27E25/10/6-3E27E25/13/7-3E27E30/15/7-3E27E34/14/9-3E27E41/17/12-3E27E42/21/15-3E27E55/28/21-3E27EP10-3E27EP13-3E27EP17-3E27EP7-3E27PLT22/10/4-3E27P14/8-3E27P18/11-3E27P22/13-3E27P26/16-3E27P26/16-3E27-HP30/19-3E27P36/22-3E27P42/29-3E27P9/5-3E27PT14/8-3E27PT18/11-3E27PT23/11-3E27PT23/18-3E27PTS14/8-3E27PTS18/11-3E27PTS23/11-3E27RM5/I-3E4RM5/I-3E27RM7/I-3E27RM8/I-3E27RM8/I-3E4RM10/I-3E27RM6S/I-3E27-XRM6S/I-3E27RM6S/I-3E4E28/14.5/11.2-3E5-/EE28/14.2/11.2-3E5EFD15/8/5-3E5-S/EEP10-3E5EP13-3E5EP7-3E5-XEP7-3E5ER11/2.5/6-3E5-SER9.5/2.5/5-3E5-SP30/19-3E5RM4/I-3E5RM5/I-3E5RM7/I-3E5RM8/I-3E5RM10/I-3E5RM14/I-3E5RM6S/I-3E5RM4/ILP-3E5RM5/ILP-3E5RM6S/ILP-3E5E14/3.5/5-3E6E18/4/10-3E6E22/6/16-3E6E25/10/6-3E6E14/3.5/5/R-3E6E18/4/10/R-3E6E22/6/16/R-3E6EP10-3E6EP13-3E6EP5-3E6EP7-3E6EPX7-3E6EPX9-3E6ER11/2.5/6-3E6-SER14.5/3/7-3E6-SER9.5/2.5/5-3E6-SEPX10-3E6MHR2-32/12/6-3E6-MPLT14/5/1.5-3E6PLT18/10/2-3E6PLT22/16/2.5-3E6PLT14/5/1.5/S-3E6PLT18/10/2/S-3E6PLT22/16/2.5/S-3E6RM4/I-3E6RM5/I-3E6RM8/I-3E6RM6S/I-3E6RM4/ILP-3E6RM5/ILP-3E6RM8/ILP-3E6RM10/ILP-3E6RM6S/ILP-3E6TC3.1/1.8/2-3E28TC3.5/1.8/1.8-3E28TC3.9/1.8/2.5-3E28-SPTC5.8/3.1/3.2-3E28TC6/3/1.5-3E28TC8.2/3.7/2-3E28TX13/7.9/5.1-3E28-C2TX25/15/12-3E28TX36/23/15-3E28-C3TX39/20/13-3E28-C3TX8.2/3.7/2-3E28EP10-3E55EP13-3E55EP5-3E55EP7-3E55EPX8-3E55EPX9-3E55EPX10-3E55RM8/I-3E55EP13-3B46EP7-3B46EPX7-3B46EPX9-3B46-/EEPX9-3B46RM4/I-3B46RM5/I-3B46RM8/I-3B46RM6S/I-3B46RM6S/ILP-3B46BLK104/66/17-3B7PH9.4/4.5-3B7-/MP11/7-3B7P14/8-3B7P18/11-3B7P22/13-3B7P26/16-3B7P26/16-3B7/NP30/19-3B7P36/22-3B7P36/22-3B7/NP42/29-3B7P9/5-3B7PT14/8-3B7RM5-3B7RM8-3B7RM10-3B7RM6R-3B7RM6S-3B7TC3.4/1.8/1.3-3B7TC3.4/1.8/1.3-3B7-SPTC3.9/2.2/1.3-3B7-MTC3.9/2.2/1.3-3B7-SPT***/2.2/1.4-3B7-MT***.8/2.3/1.3-3B7T***.8/2.3/1.3-3B7-SPTC5.8/3.1/1.5-3B7TC5.8/3.1/1.5-3B7-SPTC5.8/3.1/3.2-3B7TC9.5/4.8/3.2-3B7TN16/9.6/6.3-3B7TN19/11/10-3B7T16/9.6/6.3-3B7TX13/7.1/4.8-3B7H10-3D3PH14/7.5-3D3PH5.6/3.6-3D3PH7.4/3.9-3D3PH9.0/1.0-3D3PH9.4/3.3-3D3PH9.4/4.8-3D3P11/7-3D3P14/8-3D3-/P2P14/8-3D3P14/8-3D3-/PP18/11-3D3P22/13-3D3P22/13-3D3-/PP26/16-3D3P36/22-3D3P5.5/3.6-3D3P7.4/4.2-3D3P9/5-3D3RM4-3D3RM5-3D3RM8-3D3RM8-3D3-/NRM6S-3D3RM10/I-3D3RM6S/I-3D3RM8/ILP-3D3TC3.4/1.8/1.3-3D3TC3.9/2.2/1.3-3D3TC5.8/3.1/1.5-3D3TC9.5/4.8/3.2-3D3TN10/6/4-3D3TN10/6/4-3D3-M2如下：)