Power supply system and power supply method for electric equipment

The invention relates to the field of a control technology, specifically to a power supply system and a power supply method for electric equipment, and aims to solve the problem of waste of residual electric quantity of a power-supply device caused by that when the power-supply device is in low battery, the power supply device cannot continue to supply power to electric equipment. The embodiment of the invention provides the power supply system for the electric equipment; the power supply system comprises a main battery and a backup energy storage module; the power supply system also comprises a voltage detection module, a voltage reduction module and a current limiting module. When the voltage of the main battery of the power supply system is insufficient, the voltage reduction module begins to work for outputting the electric energy of the backup energy storage module in a constant discharging current manner so as to supply electric energy to the electric equipment along with the main battery until all the electric energy of the main battery is consumed, so that the electric energy of the main battery can be fully utilized.