Patent ID: 9692255
Date: 2017-06-27
CPC Classifications: G01R,H02J,H02M

Claim:
1. A control method for implementation in a power supply system, the power supply system including a converter circuit, an output capacitor electrically coupled with the converter circuit, and a control circuit electrically coupled with the converter circuit and the output capacitor, the power supply system being configured to provide electricity to a load, the control method comprising: (A) while the power supply system is providing electricity to the load, determining, using the control circuit, an estimated capacitance value related to the output capacitor; (B) while the output capacitor is providing electricity to the load, determining, using the control circuit, an average power value related to the electricity provided by the output capacitor to the load; and (C) determining, using the control circuit, an estimated hold-up time value related to the power supply system based on a predetermined target voltage value, a predetermined minimum voltage value, the average power value and the estimated capacitance value, wherein the predetermined target voltage value is associated with an amount of electricity required by the output capacitor for hold-up operation of the power supply system and provided by the converter circuit to the output capacitor, and wherein the predetermined minimum voltage value is associated with a minimum voltage of the output capacitor; wherein, in (A), the control circuit determines the estimated capacitance value based on an initial voltage of the output capacitor at the beginning of a time interval, and a final voltage of the output capacitor at the end of the time interval; wherein, in (A), the time interval is related to the output capacitor discharging electricity to the load, and the initial voltage of the output capacitor is greater than the final voltage of the output capacitor; wherein determining the estimated capacitance value in (A) includes: (A1) the control circuit determining whether the voltage of the output capacitor is at a predetermined high voltage value corresponding to the initial voltage of the output capacitor; (A2) when the control circuit determines that the voltage of the output capacitor is at the predetermined high voltage value in (A1), the control circuit controlling the converter circuit to stop supplying electricity to the output capacitor such that the output capacitor discharges electricity to the load, and the control circuit recording an initial time related to start of discharging by the output capacitor; (A3) the control circuit determining whether the voltage of the output capacitor is at a predetermined low voltage value corresponding to the final voltage of the output capacitor; (A4) when the control circuit determines that the voltage of the output capacitor is at the predetermined low voltage value in (A3), the control circuit recording a final time related to end of discharging by the output capacitor; (A5) the control circuit determining an average power value related to the electricity discharged by the output capacitor within the time interval; and (A6) the control circuit determining the estimated capacitance value based on the predetermined high voltage value, the predetermined low voltage value, the average power value, the initial time and the final time.