Patent ID: 9647530
Date: 2017-05-09
CPC Classifications: G01R,H02M

Claim:
1. A switching power supply, comprising: a power supply control unit configured to output a PWM waveform for controlling an input voltage to be a constant output voltage; and a choke coil and an output capacitor configured to smooth the PWM waveform output by the power supply control unit, the switching power supply further comprising: a switching frequency monitoring unit configured to measure a switching frequency of the PWM waveform; and an alarm output unit configured to determine whether or not the switching frequency measured by the switching frequency monitoring unit is within a predetermined frequency range and output a preventive maintenance alarm if the switching frequency is not within the range, wherein the power supply control unit is configured to perform control such that the switching frequency deviates from the predetermined frequency range before the output voltage deviates from a predetermined voltage range due to degradation of the choke coil and the output capacitor.