High-frequency response and ns-range pulse response of iron-based amorphous cores

In order to get important characteristic parameters of three kinds of domestic amorphous cores under the conditions of high frequency and fast pulses, frequency response and fast-pulse response of these cores are analyzed in detail in this paper. In the test circuit of a 1:1 transformer,attenuation ratio of the response Jantage increased from 0 to 50%∼60% when the frequency of the sinusoidal source Jantage increased from 1 MHz to 20 MHz. According to theoretical analysis, high-frequency eddy loss caused this voltage attenuation.Fast-pulse response of amorphous cores were also studied, and experimental results showed that these cores responded inferiorly to the amplitude and flat top of the square pulse when the pulse width was less than 30 ns. However, response signal and source signal corresponded to each other when the pulse width was no less than 100 ns, and the shortest pulse response time was about 10 ns. The relation between relative permeability and signal frequency were tested with the frequency ranging from 20 Hz to 1 MHz. This paper also introduces a test method for pulse permeability of cores and analyzes the experimental results by comparisons. (authors)