Method and system for correcting a power factor of a storage subsystem

A storage subsystem that utilizes power factor correction circuitry to solve an input current harmonics problem caused by one or more accessory units that are added to the storage subsystem. The circuit may be characterized as a boost AC/AC power converter and utilizes active current shaping to achieve a unity power factor. It utilizes pulse width modulation (PWM) or pulse amplitude modulation (PAM) as a means of accomplishing this shaping. The modulation in the circuitry is controlled by a combination of an inner average-current loop and an outer voltage-control loop. Together, these control loops maintain a regulated output voltage while forcing the input current to be sinusoidal. Using such a circuit may eliminate the necessity of modifying either the power supply of accessory units or the rack electrical distribution system within the storage subsystem.