Fabrication of a Simple Computerized High Power Supply for Magnetic Measurements

Abstract

A High current power supply was built and controlled by a personal computer using a simple design and a low-cost components for magnetic measurement applications. The design depends on the Arduino Uno board and Scilab software. Three Scilab block diagrams were given to simulate three magnetic tests, which are constant field block diagram (single field value), increasing and decreasing fields for FMR and magnetocaloric tests, and field for hysteresis loop test. Each Scilab block diagram contained different xcos blocks to control the Arduino output voltage and other blocks to sense, read, and calibrate the field value. This control was done via controlling pulse width modulation in the range (0-255). The output of each block diagram was simulated by measuring its variation with time using a cscope block display. The Arduino signal was amplified by a simple electronic circuit that involved two stages, BUL680 transistor as the first stage. Two high-power transistors EVK71-050 or Q50z were used in the second stage. The output of 107V-39.8A from the first one and 108V- 39.7A from the second one produces a magnetic field of about 30000Oe. The linearity between the current and the field value is better for Q50z due to the variation of α with the wide variation of collector current.