Design of constant current source to drive analog coil of space magnetic environment

To reach the requirements that the space environment simulation coil's magnetic induction intensity can continuously adjust from 0 to 20 Gs, and the magnetic field stability can be better than 1%, main circuit topology structure using a voltage source in series with a current source, combined with the voltage double closed loop control and the current closed loop negative feedback control methods, achieved a stable current output, reduced the power consumption of the metal-oxide-semiconductor field-effect transistor (MOSFET), and improved the efficiency of the constant current source. The test results show that the constant current source output current ranges from 0 to 10 A, Helmholtz coil's center magnetic induction intensity can reach the design requirements of 20 Gs, the current stability is better than 0.1%, and the magnetic field stability is better than 1%.