METHOD FOR CAPACITOR PRECHARGING AND CAPACITANCE MEASUREMENT IN ELECTRIC VEHICLE DRIVE SYSTEM

Provided is a control method for a power supply. The control method is for the power supply in which a link capacitor is connected between an external load and a power relay assembly (PRA) including a precharge resistor to control a power flow between a battery and the external load, the control method including: initiating precharge; after the initiating of the precharge, measuring the voltage of the link capacitor by measuring first, second, and third voltages V1, V2, and V3 of the link capacitor at different first, second, and third times T1, T2, and T3; calculating the capacitance C of the link capacitor using the first, second, and third voltages V1, V2, and V3; and terminating the precharge. Therefore, it is possible to calculate the capacitance of the link capacitor functioning as a buffer between the battery of the power supply and the external load while being charged and discharged.