This paper analyzes a magnetic torquer for satellite attitude control which requires very little energy, or average power, to control its magnetic moment. The magnetic torquer consists of a solenoid with a hard magnetic-material core that has a large residual intensity of magnetization. Discharging capacitors through the solenoid winding generates current pulses to switch the polarity of the residual intensity of magnetization in order to control the magnetic moment of the magnetic torquer. A mathematical model and design equations are presented for the magnetic torquer
