A current stabilizer is a device used to stabilize the circuit current and keep the load current constant when the input voltage and load impedance change. The current stabilizer is used to supply power to the focus coil of the cathode ray tube with magnetic deflection, the filament of the electron tube that is sensitive to the change of the filament current, the coil of the special electromagnet, the excitation coil of the speed generator whose output voltage is strictly proportional to the number of revolutions, etc. . In some magnetic amplifiers, it is also appropriate to use a current regulator to supply power.