Under the complex operating conditions of power electronic equipment, different types of oriented silicon steels exhibit different magnetic properties. In order to enable designers to quickly and accurately select different types of oriented silicon steel in the face of different operating conditions of power electronic equipment, the magnetic characteristics of 0.10mm ultra-thin oriented silicon steel and 0.23mm ordinary thickness oriented silicon steel under different operating conditions are measured based on the medium frequency Epstein square ring measuring device. The variation of magnetic properties of two different types of oriented silicon steels is revealed. By comparing the magnetic characteristics of two kinds of oriented silicon steel under different frequency sinusoidal magnetization, PWM pulse magnetization and special pulse magnetization conditions, the selection suggestions of two types of oriented silicon steel under different operating conditions are given, which provides data support for the design of power electronic equipment.
By comparing the measurement results of magnetic properties of GT100 ultra-thin oriented silicon steel and 23QG100 oriented silicon steel under different operating conditions, conclusions and selection suggestions can be drawn. First, under sinusoidal magnetization condition, the loss critical frequency of the two oriented silicon steels is 200 Hz. When the frequency is less than 200 Hz, 23QG100 oriented silicon steel has high permeability and low loss. When the frequency is greater than 200 Hz, the permeability and loss characteristics of 23QG100 oriented silicon steel decrease obviously, and the permeability and loss performance of GT100 ultra-thin oriented silicon steel is better.
Cold rolled grain oriented electrical steel
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Under PWM excitation condition, the magnetic characteristics of the two orientations are basically the same. When the modulation ratio is constant, the loss of oriented silicon steel decreases with the increase of carrier ratio. When the carrier ratio is constant, the loss of oriented silicon steel increases as the modulation ratio decreases.
Under the same PWM excitation condition, the choice of GT100 ultra-thin oriented silicon steel and 23QG100 oriented silicon steel depends on the modulation wave frequency, and the performance of GT100 ultra-thin oriented silicon steel is better when the modulation wave frequency is high. Compared with sinusoidal magnetization with different frequencies, the critical frequency of loss of GT100 ultra-thin oriented silicon steel and 23QG100 oriented silicon steel is lower under PWM pulse modulation condition, which is less than 200 Hz under sinusoidal magnetization condition, and the applicable frequency of 23QG100 oriented silicon steel is reduced.
The operation condition of the saturated reactor used in DC converter valve is a special pulse oscillation condition. The pulse occurrence and oscillation duration are relatively short compared with the magnetization period, which has the characteristics of high frequency magnetization. Under special excitation conditions with high frequency magnetization, GT100 ultra-thin oriented silicon steel has obvious advantages.
