Thin film core for high frequency power converter of artificial satellite.

为了获得紧凑型人造卫星电源，对工作在MHz频段的磁性薄膜功率芯进行了研究，得到了以下结果：(1)采用溅射工艺研究了2微米厚的高性能CoZrMo薄膜功率芯，确定了制备条件。在此基础上研制了磁芯缠绕磁芯，磁芯的矫直力为4.8A/m，在10 MHz，0.1T的功率损耗为5微米厚的超马来合金磁芯的五分之一。为了实用高频变压器，研究了人工分层CoZrMo+SiO_2磁芯，磁芯的矫顽力为2.8A/m。(2)研制了一套工作在方波电压下的高频铁损测量系统。测量结果表明，某些材料在方波电压激励下的功率损耗小于正弦电压激励下的功率损耗。由于开关变流器通常由方波电压源驱动，因此最好将其应用于开关变流器。(3)研制了一种基于图像处理技术的动态域观测系统。这对于研究薄膜磁芯中产生涡流损耗的机理是有用的。(4)提出了一种仅由铁氧体磁芯制成的紧凑型L/C元件。这是多功能操作的，并且有可能实现包括磁性材料的紧凑型电子电路。研究了等效铁损电阻的物理意义。它是等效磁滞电阻和等效涡流电阻的并联组合。前者依赖于斯坦梅兹常数，而后者强烈依赖于磁畴构型。

In order to obtain compact powers supplies for artificial satellites, magnetic thin film power cores operating in MHZ band are studied and the following results are obtained.(1)2mum thick CoZrMo thin film cores with high performance are studied using sputtering process and the manufacturing condition is decided. The coercivity of ring core is 4.8A/m and the power loss at 10MHz ,0.1T is one fifth of 5mum thick Supermalloy core.Based on this success tape wound cores were developed and the coercivity is 4A/m. For the purpose of practical high frequency transformers artificially stratified CoZrMo+SiO_2 magnetic cores were studied and the coercivity is 2.8A/m.(2)A high frequency iron loss measuring system operating under square wave voltage is developed for evaluating the high frequency characteristics of thin film cores. The measuring results shows that some materials has less power loss under square wave voltage excitation than in sinusoidal voltage excitation. It is better to apply these materials for switching converters since the converters are usually driven by the square wave voltage source.(3)A dynamic domain observation system using image processing technique is developed. This is useful for studying the mechanism generating eddy current loss in thin film cores.(4)A compact L/C element made of ferrite core only is proposed. This operates multifunctionally and has a possibility realizing compact electronic circuits including magnetic materials. This idea proposes a clue for magnetic integrated circuit.(5)Physical meaning of equivalent core loss resistance is studied. It is the parallel combination of equivalent hysteresis resistance and equivalent eddy current resistance. The former is dependent on the Steinmetz constant and the latter depends strongly upon the magnetic domain configurations.