Non-linear carrier controllers for high power factor rectification

In a boost rectifier a method to emulate a resistive load on the input power line comprising the steps of:

• sensing a current of a switching means which is located inside the rectifier, producing a voltage (V.sub.s) proportional to the current of the switch means;
• sensing a negative of the rectifier output voltage (V) and summing it with a reference voltage thereby yielding an error voltage;
• amplifying the error voltage with a voltage loop error amplifier to obtain a carrier generator input voltage (V.sub.m);
• generating a non-linear carrier waveform (V.sub.c (t)) whose amplitude is proportional to the carrier generator input voltage (V.sub.m) according to the formula:
• V.sub.c (t)=(V.sub.m +Kt/T.sub.s (1-t/T.sub.s) where T.sub.s =the switching period and t=time from the beginning of the switching period, K=VR.sub.s /2Lf.sub.s where V=the output voltage of the boost rectifier, R.sub.s =the switch current sense resistor, L=the series inductor of the boost rectifier, and f.sub.s =the switching frequency;
• using a clock to set a flip flop to turn on the switching means at the beginning of each switching period;
• and
• comparing Voltage (V.sub.s) with parabolic carrier waveform (V.sub.c (t)) and resetting the flip flop to turn off the switching means when (V.sub.s) exceeds (V.sub.c (t)).

In a boost rectifier an apparatus to emulate a resistive load on the input power line comprising:

• means for sensing a current of a switching means which is located inside the rectifier;
• means for integrating the sensed switch current to compute a voltage (V.sub.q);
• means for sensing a negative of the rectifier output voltage and summing it with a reference voltage thereby yielding an error voltage;
• means for amplifying the error voltage with a voltage loop error amplifier to obtain a carrier generator input voltage (V.sub.m);
• means for generating a non-linear carrier waveform (V.sub.c (t)) whose amplitude is proportional to the carrier generator input voltage (V.sub.m) according to the formula:
• ##EQU20## where t=time from the beginning of the switching period and T.sub.s =the switching period;
• means for using a clock to set a flip flop to turn on the switching means at the beginning of each switching period;
• and
• means for comparing Voltage (V.sub.q) with non-linear carrier waveform (V.sub.c (t)) and resetting the flip flop to turn off the switching means when (V.sub.q) exceeds (V.sub.c (t)).

In a boost rectifier an apparatus to emulate a resistive load on the input power line comprising:

• means for sensing a current of a switching means which is located inside the rectifier, producing a voltage (V.sub.s) proportional to the current of the switch means;
• means for sensing a negative of the rectifier output voltage (V) and summing it with a reference voltage thereby yielding an error voltage;
• means for amplifying the error voltage with a voltage loop error amplifier to obtain a carrier generator input voltage (V.sub.m);
• means for generating a non-linear carrier waveform (V.sub.c (t)) whose amplitude is proportional to the carrier generator input voltage (V.sub.m) according to the formula:
• V.sub.c (t)=(V.sub.m +Kt/T.sub.s)(1-t/T.sub.s) where T.sub.s =the switching period and t=time from the beginning of the switching period, K=VR.sub.s /2Lf.sub.s where V=the output voltage of the boost rectifier, R.sub.s =the switch current sense resistor, L=the series inductor of the boost rectifier, and f.sub.s =the switching frequency;
• means for using a clock to set a flip flop to turn on the switching means at the beginning of each switching period;
• and
• means for comparing Voltage (V.sub.s) with non-linear carrier waveform (V.sub.c (t)) and resetting the flip flop to turn off the switching means when (V.sub.s) exceeds (V.sub.c (t)).