Power supply apparatus and method thereof for input harmonic current suppression and output voltage regulation

A power supply apparatus, comprising:

• an input port;
• an output port;
• an energy storage device for providing a first voltage;
• a first power converter electrically connected in parallel with said input port and connected to said energy storage device for providing a first compensating voltage from said first voltage as a backup power supply;
• a link inductor electrically connected between said input port and said first power converter for providing voltage isolation between an AC power source at said input port and said first power converter;
• and
• a second power converter electrically connected in series with said output port for providing a second compensating voltage from said first voltage to maintain said output voltage at said output port.

A method of providing input harmonic current suppression, input power factor compensation, and output voltage regulation in a power supply apparatus which has an input port and an output port, wherein said power supply apparatus comprises an energy storage device for providing a first voltage, a first power converter electrically connected in parallel with said input port for providing a first compensating voltage from said first voltage, a link inductor electrically connected between said input port and said first power converter for providing isolation between an AC power source at said input port and said first power converter and a second power converter electrically connected in series with said output port for providing a second compensating voltage to maintain an output voltage at said output port, comprising the steps of:

• determining a magnitude of a first command signal;
• sensing said first voltage to obtain a feedback signal of said first voltage for subtracting a feedback signal of said first voltage from said first command signal to generate a second command signal;
• compensating said second command signal to generate a third command signal;
• capturing both phase and frequency of a sinusoidal wave of said AC power source to generate a first sinusoidal signal;
• processing a phase shift of said first sinusoidal signal to generate a second sinusoidal signal;
• multiplying said third command signal by said second sinusoidal signal to generate a fourth command signal;
• subtracting an input voltage signal by said fourth command signal to generate a fifth command signal;
• subtracting a feedback signal of said first compensating voltage from said fifth command signal to generate a sixth command signal;
• processing a signal processing of said sixth command signal to generate a first modulation signal;
• transforming said first modulation signal to generate a first pulse width modulation signal which operates said first power converter to provide said first compensating voltage, thereby causing said input current as a substantial sinusoidal wave and in phase with said input voltage;
• determining a seventh command signal;
• processing a phase shift of said seventh command signal to generate a capacitor current command signal;
• subtracting a feedback signal of said output voltage from said seventh command signal to generate an eighth command signal;
• compensating said eighth command signal to generate a ninth command signal;
• subtracting said ninth command signal from said capacitor current command signal and adding a feedback signal of said output current signal to generate a tenth command signal;
• subtracting a feedback signal of a secondary winding current from said tenth command signal to generate an eleventh command signal;
• processing a signal processing of said eleventh command signal to generate a second modulation signal;
• and
• transforming said second modulation signal to a second pulse width modulation signal which operates said second power converter to provide said second voltage to maintain said output voltage at a desired level.